Ten years of global burned area products from spaceborne remote sensing - A review: Analysis of user needs and recommendations for future developments
---
paper_title: Biomass burning in the tropics: impact on atmospheric chemistry and biogeochemical cycles.

paper_content:

Biomass burning is widespread, especially in the tropics. It serves to clear land for shifting cultivation, to convert forests to agricultural and pastoral lands, and to remove dry vegetation in order to promote agricultural productivity and the growth of higher yield grasses. Furthermore, much agricultural waste and fuel wood is being combusted, particularly in developing countries. Biomass containing 2 to 5 petagrams of carbon is burned annually (1 petagram = 10(15) grams), producing large amounts of trace gases and aerosol particles that play important roles in atmospheric chemistry and climate. Emissions of carbon monoxide and methane by biomass burning affect the oxidation efficiency of the atmosphere by reacting with hydroxyl radicals, and emissions of nitric oxide and hydrocarbons lead to high ozone concentrations in the tropics during the dry season. Large quantities of smoke particles are produced as well, and these can serve as cloud condensation nuclei. These particles may thus substantially influence cloud microphysical and optical properties, an effect that could have repercussions for the radiation budget and the hydrological cycle in the tropics. Widespread burning may also disturb biogeochemical cycles, especially that of nitrogen. About 50 percent of the nitrogen in the biomass fuel can be released as molecular nitrogen. This pyrdenitrification process causes a sizable loss of fixed nitrogen in tropical ecosystems, in the range of 10 to 20 teragrams per year (1 teragram = 10(12) grams).
---
paper_title: Biomass Burning as a Source of Atmospheric Gases CO, H2, N2O, NO, CH3Cl and COS

paper_content:

The potential importance of deforestation and biomass burning for the atmospheric CO2 cycle has received much attention and caused some controversy. Biomass burning can contribute extensively to the budgets of several gases which are important in atmospheric chemistry. In several cases the emission is comparable to the technological source. Most burning takes place in the tropics in the dry season and is caused by man’s activities. The potential importance of deforestation and biomass burning for the atmospheric CO2 cycle has received much attention and caused some controversy. In this article we will show the probable importance of biomass burning as a trace gas source, which is caused by man’s activities in the tropics. We used the results of our global biomass burning analysis to derive some rough estimates of the sources of the important atmospheric trace gases CO, H2, CH4, N2O, NOx (NO and NO2), COS and CH3Cl from the worldwide burning of biomass.
---
paper_title: Global spatial and temporal distribution of vegetation fire as determined from satellite observations

paper_content:

Vegetation fires occur worldwide, all year round and inject enormous amounts of trace gases and particles into the atmosphere. Nonetheless, there is still great uncertainty as to the global spatial and temporal distribution of vegetation fires. Twenty one months of global, daily, daytime satellite data at 1 km resolution, from April 1992 to December 1993, were processed in order to determine the positions of active vegetation fires. Results from the first twelve months of the study period are presented here. This is the first time that such a global study has been carried out using a long time series data set and a single processing technique. The data set and results discussed provide much improved information on the spatial variability and the seasonality of vegetation fires. They will be of use in the global mapping and modelling of emissions due to biomass burning as well as in the study of the role of fire in land cover maintenance and change. We show that half of the fires detected were on the Afric...
---
paper_title: Appraisal of fire damage and inventory for timber salvage by remote sensing in mountain ash forests in Victoria

paper_content:

Summary In 1983 the most severe fire in Victorian mountain forests for over forty years killed extensive areas of highly productive eucalypt forest, requiring a large scale timber salvage and forest rehabilitation program. The scheduling of these programs was dependent upon a rapid and reliable assessment of the extent and severity of damage. Damage assessment, initiated immediately following the fire, utilised five distinct but complementary phases of remote sensing, namely airborne infrared scanning, conventional colour aerial photography from both large and small format cameras and Landsat imagery in pictorial and digital forms. The paper describes how this combination of remote sensing media offered a practical and successful solution to the problem of providing accurate and timely resources data for planning purposes.
---
paper_title: The use of remote sensing in mapping and monitoring vegetational change associated with bushfire events in Eastern Australia

paper_content:

Abstract The value of Landsat data for spatial analysis in land cover studies is well known. Potentially as valuable is its use in forecasting and monitoring temporal land cover changes such as those associated with floods, drought and bushfires. Fire is both an important component in the ecology of many natural environments and a potential hazard to human life and property. This paper examines ways Landsat data have been used to map and monitor bushfire occurrences in the Blue Mountains region of Eastern Australia. While Landsat has limited application to monitoring short‐term fire occurrences, it has proved extremely useful in mapping extended fire events in inaccessible and inhospitable regions. Analysis of the change in the spectral reflectance values of multitemporal image sets provide an indication of vegetation regrowth. Linked with suitable ground‐truth information this data can be used to monitor and map the sequence of post‐fire vegetation regeneration. Integration of field information on the st...
---
paper_title: Annual carbon balance of Canada's forests during 1895–1996

paper_content:

This paper reports annual carbon (C) balance of Canada's forests during 1895-1996 estimated using the Integrated Terrestrial Ecosystem C-budget model (InTEC) [Chen et. al., this issue]. During 1895-1910, Canada's forests were small sources of 30±15 Tg C yr -1 due to large disturbances (forest fire, insect-induced mortality, and harvest) in late nineteenth century. The forests became large sinks of 170±85 Tg C yr -1 during 1930-1970, owing to forest regrowth in previously disturbed areas and growth stimulation by nondisturbance factors such as climate, atmospheric CO 2 concentration, and N deposition. In recent decades (1980-1996), Canada's forests have been moderate sinks of 50±25 Tg C yr -1 , as a result of a tradeoff between the negative effects of increased disturbances and positive effects of nondisturbance factors. The nondisturbance factors, in order of importance, are (1) atmospheric N deposition (measured by a national monitoring network), (2) net N mineralization and fixation (estimated from temperature and precipitation records), (3) growing season length increase (estimated from spring air temperature records), and (4) CO 2 fertilization (estimated from CO 2 records using a leaf-level photosynthesis model). The magnitudes of modeled nondisturbance effects are consistent with simulation results by the Carnegie-Ames-Stanford Approach (CASA) and are also in broad agreement with flux measurements above mature forest stands at several locations in Canada. Results for the disturbance effects agree with a previous study [Kurz and Apps, 1996]. The overall C balance from InTEC generally agrees with that derived from tree ring data [Auclair and Bedford, 1997] and from forest inventories. The combination of our result and that of Houghton et al. [1999] for the United States suggests that North America (> 15°N), was probably a C sink of 0.2-0.5 Pg C yr -1 during 1980s, much less than that of 1.7 Pg C yr -1 estimated by Fan et al. [1998] using an atmospheric inversion method.
---
paper_title: Spatial and temporal distribution of tropical biomass burning

paper_content:

A database for the spatial and temporal distribution of the amount of biomass burned in tropical America, Africa, and Asia during the late 1970s is presented with a resolution of 5{degrees} latitude x 5{degrees} longitude. The sources of burning in each grid cell have been quantified. Savanna fires, shifting cultivation, deforestation, fuel wood use, and burning of agricultural residues contribute about 50, 24, 10, 11, and 5%, respectively, of total biomass burned in the tropics. Savanna fires dominate in tropical Africa, and forest fires dominant in tropical Asia. A similar amount of biomass is burned from forest and savanna fires in tropical America. The distribution of biomass burned monthly during the dry season has been derived for each grid cell using the seasonal cycles of surface ozone concentrations. Land use changes during the last decade could have a profound impact on the amount of biomass burned and the amount of trace gases and aerosol particles emitted. 32 refs., 3 figs., 3 tabs.
---
paper_title: An assessment of vegetation fire in Africa (1981–1991): Burned areas, burned biomass, and atmospheric emissions

paper_content:

This paper presents the first published time series of burned area maps of Africa, covering an 8 year period, 1981–1983 and 1985–1991. These maps were derived from the analysis of the advanced very high resolution radiometer (AVHRR) global area coverage (GAC) images at 5 km resolution. The burned area maps for the period 1985–1991 were used with biomass density and burning efficiency figures, to estimate the quantity of burned biomass during this 6 year period. Emission factors were further used to estimate the trace gas and aerosol emissions produced by vegetation fires. Biomass density was estimated based on values found in the literature and on the accumulated normalized difference vegetation index (NDVI) as derived from the remote sensing images. Burning efficiency was assessed with a dryness index that was based on the relative greenness index (RGI), also derived from the NDVI. Average emission factors were retrieved from the literature. The uncertainties in the burned area, biomass density, combustion efficiency, and emission factors were considered, with a total error of 51% for the burned biomass and 58% for the emission estimates. The results obtained for the burned biomass in Africa were compared with other values found in the literature and showed values lower by a factor of 1.1–3.3. The annual burned biomass from vegetation fires in Africa on average was estimated between 704 and 2168 Tg . In the same way, the atmospheric emissions on average ranges are as follows: CO2 (990–3726 Tg), CO (40–151 Tg), CH4 (1.2–4.4 Tg), NOx (2.8–10.6 Tg), and PM (< 2.5 μm) (3.3–12.4Tg).
---
paper_title: Mapping and inventory of forest fires from digital processing of tm data

paper_content:

Abstract The application of space‐borne sensors to forest fire mapping and inventory was evaluated. Digital image processing of Thematic Mapper data was used to study a big forest fire on the Mediterranean coast of Spain. The results showed that image processing techniques cannot discriminate perfectly the area affected by the fire. The main problem was spectral overlapping between burned and unburned vegetation especially caused by the sparseness of shrub and confusion with other cover types such as urban/rural villages. Most of these problems can be solved by using visual analysis for masking the affected area, although this strategy is not completely reliable on studies of small forest fires. An inventory of the damaged area was performed in three levels: total area affected by the fire, area by previous vegetation species, and identification of levels of damaged on the burned vegetation.
---
paper_title: An active-fire based burned area mapping algorithm for the MODIS sensor

paper_content:

We present an automated method for mapping burned areas using 500-m Moderate Resolution Imaging Spectroradiometer (MODIS) imagery coupled with 1-km MODIS active fire observations. The algorithm applies dynamic thresholds to composite imagery generated from a burn-sensitive vegetation index and a measure of temporal texture. Cumulative active fire maps are used to guide the selection of burned and unburned training samples. An accuracy assessment for three geographically diverse regions (central Siberia, the western United States, and southern Africa) was performed using high resolution burned area maps derived from Landsat imagery. Mapped burned areas were accurate to within approximately 10% in all regions except the high-tree-cover sub-region of southern Africa, where the MODIS burn maps underestimated the area burned by 41%. We estimate the minimum detectable burn size for reliable detection by our algorithm to be on the order of 120 ha.
---
paper_title: Vegetation burning in the year 2000: Global burned area estimates from SPOT VEGETATION data

paper_content:

[1] The scientific community interested in atmospheric chemistry, gas emissions from vegetation fires, and carbon cycling is currently demanding information on the extent and timing of biomass burning at the global scale. In fact, the area and type of vegetation that is burned on a monthly or annual basis are two of the parameters that provide the greatest uncertainty in the calculation of gas and aerosol emissions and burned biomass. To address this need, an inventory of burned areas at monthly time periods for the year 2000 at a resolution of 1 km2 has been produced using satellite data and has been made freely available to the scientific community. In this paper, estimates of burned area and number of burn scars for four broad vegetation classes and reported at the country level for the year 2000 are presented using data taken from the inventory. Over 3.5 million km2 of burned areas were detected in the year 2000, of which approximately 80% occurred in areas described as woodlands and shrublands. Approximately 17% of the burned area occurred in grasslands and croplands, the remaining 3% occurred in forests. Almost 600,000 separate burn scars were detected. Descriptions of vegetation burning activity are given for ten regions. Finally, monthly burned area estimates are presented for the Central African Republic to illustrate the usefulness of these data for understanding, monitoring and managing vegetation burning activities.
---
paper_title: The role of fire disturbance for global vegetation dynamics: coupling fire into a Dynamic Global Vegetation Model

paper_content:

Disturbances from fire, wind-throw, insects and other herbivores are, besides climate, CO 2 , and soils, critical factors for composition, structure and dynamics of most vegetation. To simulate the influence of fire on the dynamic equilibrium, as well as on potential change, of vegetation at the global scale, we have developed a fire model, running inside the modular framework of the Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ-DGVM). 2 Estimated litter moisture is the main driver of day-to-day fire probability. The length of the fire season is used to estimate the fractional area of a grid cell which is burnt in a given year. This affected area is converted into an average fire return interval which can be compared to observations. 3 When driven by observed climate for the 20th century (at a 0.5 ° longitude/latitude resolution), the model yielded fire return intervals in good agreement with observations for many regions (except parts of semiarid Africa and boreal Siberia). We suggest that further improvement for these regions must involve additional process descriptions such as permafrost and fuel/fire dynamics.
---
paper_title: Simulating energy and carbon fluxes over winter wheat using coupled land surface and terrestrial ecosystem models, Agric

paper_content:

Coupled land surface and terrestrial ecosystem models are used to simulate energy and carbon fluxes over winter wheat at the Ponca City, Oklahoma, Ameriflux site. The terrestrial ecosystem model consists of photosynthesis and respiration (autotrophic and heterotrophic) sub-modules, which uses canopy temperature, soil moisture, and soil temperature simulated by the land surface scheme. The photosynthesis sub-module, which provides an estimate of canopy conductance to the land surface scheme, is designed to use both the big- and the two-leaf (sunlit/shaded) approaches, and canopy conductance formulations based on both relative humidity and vapor pressure deficit. This provides a tool to test the sensitivity of model results to these two different approaches of modeling photosynthesis and stomatal conductance. Model results for carbon and energy fluxes compare well with observations over the growing season of 1997, especially with the use of the two-leaf model and stomatal conductance formulation based on vapor pressure deficit. Averaged over the growing season, the model results suggest that for this particular site, the difference in simulated latent heat fluxes caused by the choice of the photosynthesis approach (bigor two-leaf) is smaller (∼1%) than the difference caused by the choice of the stomatal conductance formulation (∼10%). In regard to the carbon fluxes, averaged over the growing season and compared with the two-leaf model, the simulated net photosynthesis rate and net ecosystem exchange flux are about 5 and 18% higher, respectively, for the big-leaf model. It is shown that comparisons with both observed energy and carbon fluxes are necessary to constrain model behavior and test its performance adequately. Crown Copyright © 2003 Published by Elsevier B.V. All rights reserved.
---
paper_title: Fire as an interactive component of dynamic vegetation models

paper_content:

[1] Fire affects ecosystems by altering both their structure and the cycling of carbon and nutrients. The emissions from fires represent an important biogeochemical pathway by which the biosphere affects climate. For climate change studies it is important to model fire as a mechanistic climate-dependent process in dynamic global vegetation models (DGVMs) and the terrestrial ecosystem components of climate models. We expand on those current approaches which neglect disturbance by fire, which use constant specified loss rates, or which depend on simple empirical relationships, and develop a process-based fire parameterization for use in the terrestrial ecosystem components of climate and Earth system models. The approach is straightforward and general enough to apply globally and for current and future climates. All three aspects of the fire triangle, fuel availability, the readiness of fuel to burn depending on conditions, and the presence of an ignition source, are taken into account. The approach also represents some anthropogenic effects on natural fire regimes, albeit in a simple manner. The fire parameterization is incorporated in the Canadian Terrestrial Ecosystem Model (CTEM) which simulates net primary productivity, leaf area index, and vegetation biomass. The fire parameterization generates burned area, alters vegetation biomass, and generates CO2 emissions. The parameterization is tested by comparing simulated fire return intervals and CO2 emissions with observation-based estimates for tropical savanna, tropical humid forests, mediterranean, and boreal forest locations.
---
paper_title: Vegetation burning in the year 2000: Global burned area estimates from SPOT VEGETATION data

paper_content:

[1] The scientific community interested in atmospheric chemistry, gas emissions from vegetation fires, and carbon cycling is currently demanding information on the extent and timing of biomass burning at the global scale. In fact, the area and type of vegetation that is burned on a monthly or annual basis are two of the parameters that provide the greatest uncertainty in the calculation of gas and aerosol emissions and burned biomass. To address this need, an inventory of burned areas at monthly time periods for the year 2000 at a resolution of 1 km2 has been produced using satellite data and has been made freely available to the scientific community. In this paper, estimates of burned area and number of burn scars for four broad vegetation classes and reported at the country level for the year 2000 are presented using data taken from the inventory. Over 3.5 million km2 of burned areas were detected in the year 2000, of which approximately 80% occurred in areas described as woodlands and shrublands. Approximately 17% of the burned area occurred in grasslands and croplands, the remaining 3% occurred in forests. Almost 600,000 separate burn scars were detected. Descriptions of vegetation burning activity are given for ten regions. Finally, monthly burned area estimates are presented for the Central African Republic to illustrate the usefulness of these data for understanding, monitoring and managing vegetation burning activities.
---
paper_title: THE GLOBCARBON INITIATIVE: MULTI-SENSOR ESTIMATION OF GLOBAL BIOPHYSICAL PRODUCTS FOR GLOBAL TERRESTRIAL CARBON STUDIES

paper_content:

The ESA GLOBCARBON project aims to generate fu lly calibrated estimates of at-land products quasi- independent of the original Earth Observation source for use in Dynamic Global Vegetation Models, a central component of the IGBP-IHDP-WCRP Global Carbon Cycle Joint Project. The service features global estimates of: burned area, fAPAR, LAI and vegetation growth cycle. The demonstrator focused on six complete years, from 1998 to 2003 when overlap exists between ESA Earth Observation sensors (ATSR-2, AATSR and MERIS) and the French SPOT VEGETATION sensor and was extended to process 10 years up to 2007. After analysis, by the beta user community, of the first products the implementation of the algorithms was revisited and a reprocessing initiated. This paper provides details of the GLOBCARBON project and its revised algorithms, describes the re-processed products and gives initial results of their validation.
---
paper_title: Characterizing interannual variations in global fire calendar using data from Earth observing satellites

paper_content:

Daily global observations from the Advanced Very High-Resolution Radiometers on the series of meteorological satellites operated by the National Oceanic and Atmospheric Administration between 1982 and 1999 were used to generate a new weekly global burnt surface product at a resolution of 8km. Comparison with independently available information on fire locations and timing suggest that while the time-series cannot yet be used to make accurate and quantitative estimates of global burnt area it does provide a reliable estimate of changes in location and season of burning on the global scale. This time-series was used to characterize fire activity in both northern and southern hemispheres on the basis of average seasonal cycle and interannual variability. Fire seasonality and fire distribution data sets have been combined to provide gridded maps at 0.51 resolution documenting the probability of fire occurring in any given season for any location. A multiannual variogram constructed from 17 years of observations shows
---
paper_title: Savanna fire regimes assessment with MODIS fire data : their relationship to land cover and plant species distribution in western Burkina Faso ( West Africa )

paper_content:

The West African savannas are subject to changes in fire regimes related to land use intensification, which may infer significant biological modifications. We investigated the efficiency of MODIS fire products to account for the variability of fire regimes in relation to changes in land cover and savanna vegetation. The specificity and complementarities of both MODIS active fire (MOD14A2 and MYD14A2) and burnt area (MCD45A1) products were assessed in order to characterize fire regimes and to relate them with land cover. In addition the distribution of plant species among landscape units characterised by specific fire regimes was assessed. The calculation of the mutual information made it possible to set apart species more frequent in landscapes little or not at all subject to fire and species more frequent in burnt areas. The first group is the expression of the nature of the unburnt land-cover units, made up mainly of the agricultural areas dominated by fields and fallows. It consists of more potential threats (weeds, encroachers, invasive species etc.) than the second group, which is more typical of sudanian savannas, where fire provides the long-term stability needed to preserve the ecosystem.
---
paper_title: What limits fire? An examination of drivers of burnt area in Southern Africa

paper_content:

The factors controlling the extent of fire in Africa south of the equator were investigated using moderate resolution (500 m) satellite-derived burned area maps and spatial data on the environmental factors thought to affect burnt area. A random forest regression tree procedure was used to determine the relative importance of each factor in explaining the burned area fraction and to address hypotheses concerned with human and climatic influences on the drivers of burnt area. The model explained 68% of the variance in burnt area. Tree cover, rainfall in the previous 2 years, and rainfall seasonality were the most important predictors. Human activities – represented by grazing, roads per unit area, population density, and cultivation fraction – were also shown to affect burnt area, but only in parts of the continent with specific climatic conditions, and often in ways counter to the prevailing wisdom that more human activity leads to more fire. The analysis found no indication that ignitions were limiting total burnt area on the continent, and most of the spatial variation was due to variation in fuel load and moisture. Split conditions from the regression tree identified (i) low rainfall regions, where fire is rare; (ii) regions where fire is under human control; and (iii) higher rainfall regions where burnt area is determined by rainfall seasonality. This study provides insights into the physical, climatic, and human drivers of fire and their relative importance across southern Africa, and represents the beginnings of a predictive framework for burnt area.
---
paper_title: Operational active fire mapping and burnt area identification applicable to Mexican Nature Protection Areas using MODIS and NOAA-AVHRR direct readout data

paper_content:

Abstract Since 1999, the National Commission for the Knowledge and Use of the Biodiversity (CONABIO) in Mexico has been developing and managing the “Operational program for the detection of hot-spots using remote sensing techniques”. This program uses images from the MODerate resolution Imaging Spectroradiometer (MODIS) onboard the Terra and Aqua satellites and from the Advanced Very High Resolution Radiometer of the National Oceanic and Atmospheric Administration (NOAA-AVHRR), which are operationally received through the Direct Readout station (DR) at CONABIO. This allows the near-real time monitoring of fire events in Mexico and Central America. In addition to the detection of active fires, the location of hot spots are classified with respect to vegetation types, accessibility, and risk to Nature Protection Areas (NPA). Besides the fast detection of fires, further analysis is necessary due to the considerable effects of forest fires on biodiversity and human life. This fire impact assessment is crucial to support the needs of resource managers and policy makers for adequate fire recovery and restoration actions. CONABIO attempts to meet these requirements, providing post-fire assessment products as part of the management system in particular for satellite-based burnt area mapping. This paper provides an overview of the main components of the operational system and will present an outlook to future activities and system improvements, especially the development of a burnt area product. A special focus will also be placed on the fire occurrence within NPAs of Mexico.
---
paper_title: POVERTY AND CORRUPTION COMPROMISE TROPICAL FOREST RESERVES

paper_content:

We used the global fire detection record provided by the satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS) to determine the number of fires detected inside 823 tropical and subtropical moist forest reserves and for contiguous buffer areas 5, 10, and 15 km wide. The ratio of fire detection densities (detections per square kilometer) inside reserves to their contiguous buffer areas provided an index of reserve effectiveness. Fire detection density was significantly lower inside reserves than in paired, contiguous buffer areas but varied by five orders of magnitude among reserves. The buffer : reserve detection ratio varied by up to four orders of magnitude among reserves within a single country, and median values varied by three orders of magnitude among countries. Reserves tended to be least effective at reducing fire frequency in many poorer countries and in countries beset by corruption. Countries with the most successful reserves include Costa Rica, Jamaica, Malaysia, and Taiwan and the Indonesian island of Java. Countries with the most problematic reserves include Cambodia, Guatemala, Paraguay, and Sierra Leone and the Indonesian portion of Borneo. We provide fire detection density for 3964 tropical and subtropical reserves and their buffer areas in the hope that these data will expedite further analyses that might lead to improved management of tropical reserves.
---
paper_title: Development of a framework for fire risk assessment using remote sensing and geographic information system technologies

paper_content:

Forest fires play a critical role in landscape transformation, vegetation succession, soil degradation and air quality. Improvements in fire risk estimation are vital to reduce the negative impacts of fire, either by lessen burn severity or intensity through fuel management, or by aiding the natural vegetation recovery using post-fire treatments. This paper presents the methods to generate the input variables and the risk integration developed within the Firemap project (funded under the Spanish Ministry of Science and Technology) to map wildland fire risk for several regions of Spain. After defining the conceptual scheme for fire risk assessment, the paper describes the methods used to generate the risk parameters, and presents proposals for their integration into synthetic risk indices. The generation of the input variables was based on an extensive use of geographic information system and remote sensing technologies, since the project was intended to provide a spatial and temporal assessment of risk conditions. All variables were mapped at 1 km2 spatial resolution, and were integrated into a web-mapping service system. This service was active in the summer of 2007 for semi-operational testing of end-users. The paper also presents the first validation results of the danger index, by comparing temporal trends of different danger components and fire occurrence in the different study regions.
---
paper_title: An approach to operational forest fire growth predictions for Canada

paper_content:

This paper presents an operational approach to predicting fire growth for wildland fires in Canada. The approach addresses data assimilation to provide predictions in a timely and efficient manner. Fuels and elevation grids, forecast weather, and active fire locations are entered into a fire-growth model; then predicted fire perimeters are mapped and presented on the web. The Moderate Resolution Imaging Spectroradiometer (MODIS) and the National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer (NOAA/AVHRR) satellite-based detection systems are used to detect current wildland fires (referred to as hotspots). For selected regions, fire-growth simulation environments are assembled. Fuel type data from several fire management agencies are available in grid format at a resolution of 100 m or less; in areas where such data are not available, a national fuels map based on Satellite Pour l’Observation de la Terre Vegetation sensor (SPOT VGT) land cover and forest inventory is used. Similarly, terrain data are available from a variety of sources. Current hotspots are used as ignition points while past hotspots are used to delineate area burned. Surface wind, temperature, and dew-point values (forecast by Environment Canada) are used to determine the fire weather conditions at the fire location. A case study of two large fires in Canada consisting of 54 fire simulation days is used to test these hypotheses.
---
paper_title: Multi‐year circumpolar assessment of the area burnt in boreal ecosystems using SPOT‐VEGETATION

paper_content:

The Russian Academy of Sciences' Space Research Institute has developed a new burnt area mapping method and a five-year database to estimate biomass burning in the Earth's entire boreal region. The mapping method involved SPOT-VEGETATION time-series data analysis to detect inter-annual vegetation changes combined with MODIS hot-spot data to distinguish fire-related changes from other types of disturbances. The burnt area database actually covers the boreal biome for the period 2000-2004 with 1 km spatial resolution and 10-day time frequency, while an automatic data processing chain allows this database to be updated continuously. The accuracy assessment involved comparison with Landsat-ETM+ derived burnt area estimates for Northern Eurasia and ground data for Canada. This Letter describes the satellite sensor data processing method and the results of the accuracy assessment of the burnt area database and provides burnt area statistics for the boreal region countries.
---
paper_title: Mapping canopy damage from understory fires in Amazon forests using annual time series of Landsat and MODIS data

paper_content:

article i nfo Understory fires in Amazon forests alter forest structure, species composition, and the likelihood of future disturbance. The annual extent of fire-damaged forest in Amazonia remains uncertain due to difficulties in separating burning from other types of forest damage in satellite data. We developed a new approach, the Burn Damage and Recovery (BDR) algorithm, to identify fire-related canopy damages using spatial and spectral information from multi-year time series of satellite data. The BDR approach identifies understory fires in intact and logged Amazon forests based on the reduction and recovery of live canopy cover in the years following fire damages and the size and shape of individual understory burn scars. The BDR algorithm was applied to time series of Landsat (1997-2004) and MODIS (2000-2005) data covering one Landsat scene (path/row 226/068) in southern Amazonia and the results were compared to field observations, image- derived burn scars, and independent data on selective logging and deforestation. Landsat resolution was essential for detection of burn scars b50 ha, yet these small burns contributed only 12% of all burned forest detected during 1997-2002. MODIS data were suitable for mapping medium (50-500 ha) and large (N500 ha) burn scars that accounted for the majority of all fire-damaged forests in this study. Therefore, moderate resolution satellite data may be suitable to provide estimates of the extent of fire-damaged Amazon forest at a regional scale. In the study region, Landsat-based understory fire damages in 1999 (1508 km 2 ) were an order of magnitude higher than during the 1997-1998 El Nino event (124 km 2
---
paper_title: Forest Fires in the Insular Caribbean

paper_content:

Abstract This paper presents a summary of the forest fire reports in the insular Caribbean derived from both management reports and an analysis of publicly available Moderate Resolution Imaging Spectrodiometer (MODIS) satellite active fire products from the region. A vast difference between the amount of fires reported by land managers and fire points in the MODIS Fire Information for Resource Management System data can be observed. Future research is recommended to better understand the nature of these differences. While there is a general lack of available statistical data on forest fires in the Caribbean, a few general observations can be made: Forest fires occur mainly in dry forest types (500 to 1000 mm of mean annual rainfall). These are also the areas where most human settlements are located. Lowland high forests and montane forests with higher rainfall (1000 and more mm y−1) are less susceptible to forest fire, but they can burn in exceptionally dry years. Most of the dry forest ecosystems in the ...
---
paper_title: The influence of regional surface soil moisture anomalies on forest fires in Siberia observed from satellites

paper_content:

Forest fires are frequent in the Siberian taiga and are predicted to increase in frequency as a result of increased fire risk under drought conditions, and prolonged fire seasons caused by climate change. There is, however, some uncertainty as to the extent to which drought influences forest fire frequency at a regional scale. Here, we present an analysis of satellite derived soil moisture anomaly data from ERS-1/2 (ERS: Earth Resources Satellite) scatterometer data and burned area maps from MODIS/AVHRR/ATSR (Moderate Resolution Imaging Spectroradiometer/Advanced Very High Resolution Radiometer/Along-Track Scanning Radiometer) over Central Siberia for the years 1992?2000. The purpose of this study is to investigate the relationship of remotely sensed soil moisture deviations from the long-term mean and fire within the boreal biome on a sub-continental scale. Results show that wet surface soil moisture conditions limit the extent of burned area. They can prevent the outbreak of fires but the magnitude of a negative (dry) deviation does not determine the maximum size of fire affected areas. It is known from the literature, however, that an ignition is more likely to occur under low surface wetness conditions, such as those that we observed during July and August in both permafrost and non-permafrost regions. Although the burned area under drier conditions in July is lowest over non-permafrost, the actual number of fires is as high as over continuous permafrost. Approximately 80% of all events occurred under such conditions during that month. The fire size was below 50? km2 under moist conditions. Larger burned areas have in general not been detected when the surface wetness deviation exceeded +5%.
---
paper_title: The influence of vegetation, fire spread and fire behaviour on biomass burning and trace gas emissions: results from a process-based model

paper_content:

A process-based fire regime model (SPITFIRE) has been developed, coupled with ecosystem dynamics in the LPJ Dynamic Global Vegetation Model, and used to explore fire regimes and the current impact of fire on the terrestrial carbon cycle and associated emissions of trace atmospheric constituents. The model estimates an average release of 2.24 Pg C yr−1 as CO2 from biomass burning during the 1980s and 1990s. Comparison with observed active fire counts shows that the model reproduces where fire occurs and can mimic broad geographic patterns in the peak fire season, although the predicted peak is 1–2 months late in some regions. Modelled fire season length is generally overestimated by about one month, but shows a realistic pattern of differences among biomes. Comparisons with remotely sensed burnt-area products indicate that the model reproduces broad geographic patterns of annual fractional burnt area over most regions, including the boreal forest, although interannual variability in the boreal zone is underestimated.
---
paper_title: Estimates of fire emissions from an active deforestation region in the southern Amazon based on satellite data and biogeochemical modelling

paper_content:

Abstract. Tropical deforestation contributes to the build-up of atmospheric carbon dioxide in the atmosphere. Within the deforestation process, fire is frequently used to eliminate biomass in preparation for agricultural use. Quantifying these deforestation-induced fire emissions represents a challenge, and current estimates are only available at coarse spatial resolution with large uncertainty. Here we developed a biogeochemical model using remote sensing observations of plant productivity, fire activity, and deforestation rates to estimate emissions for the Brazilian state of Mato Grosso during 2001–2005. Our model of DEforestation CArbon Fluxes (DECAF) runs at 250-m spatial resolution with a monthly time step to capture spatial and temporal heterogeneity in fire dynamics in our study area within the ''arc of deforestation'', the southern and eastern fringe of the Amazon tropical forest where agricultural expansion is most concentrated. Fire emissions estimates from our modelling framework were on average 90 Tg C year−1, mostly stemming from fires associated with deforestation (74%) with smaller contributions from fires from conversions of Cerrado or pastures to cropland (19%) and pasture fires (7%). In terms of carbon dynamics, about 80% of the aboveground living biomass and litter was combusted when forests were converted to pasture, and 89% when converted to cropland because of the highly mechanized nature of the deforestation process in Mato Grosso. The trajectory of land use change from forest to other land uses often takes more than one year, and part of the biomass that was not burned in the dry season following deforestation burned in consecutive years. This led to a partial decoupling of annual deforestation rates and fire emissions, and lowered interannual variability in fire emissions. Interannual variability in the region was somewhat dampened as well because annual emissions from fires following deforestation and from maintenance fires did not covary, although the effect was small due to the minor contribution of maintenance fires. Our results demonstrate how the DECAF model can be used to model deforestation fire emissions at relatively high spatial and temporal resolutions. Detailed model output is suitable for policy applications concerned with annual emissions estimates distributed among post-clearing land uses and science applications in combination with atmospheric emissions modelling to provide constrained global deforestation fire emissions estimates. DECAF currently estimates emissions from fire; future efforts can incorporate other aspects of net carbon emissions from deforestation including soil respiration and regrowth.
---
paper_title: Relating violence to MODIS fire detections in Darfur, Sudan

paper_content:

The Moderate Resolution Imaging Spectroradiometer (MODIS) Thermal Anomalies and Fire Detection data product can provide an input into early warning and rapid response efforts of interest to human rights, humanitarian and security communities. A review of fire detection data during a period of intense violence in Darfur, Sudan, marked by burning campaigns targeted at many settlements in the region, was conducted to test which, if any, of these fires were detected by MODIS. The results indicate that a significant portion of the fires related to violence were detected, and a relationship was found between increased fire detections and reported violence. However, underlying difficulties in the anecdotal reporting introduce uncertainties into the results. While not universally applicable, calculating increases in fire detections on a daily, global basis can possibly provide objective, satellite-based information on certain violent conflicts impacting civilian populations.
---
paper_title: Validation analyses of an operational fire monitoring product: The Hazard Mapping System

paper_content:

Vegetation fires are becoming increasingly important especially in regions where the proximity to urban areas can result in large populations being directly impacted by such events. During emergency situations, accurate fire location data becomes crucial to assess the affected areas as well as to track smoke plumes and delineate evacuation plans. In this study, the performance of the NOAA/NESDIS Hazard Mapping System (HMS) is evaluated. The system combines automated and analyst-made fire detections to monitor fires across the conterminous United States. Using 30-m-spatial-resolution ASTER imagery as the main instantaneous validation data, commission and omission error estimates are reported for a subset of HMS automated and analyst-based fire pixels derived from the Terra MODIS and GOES data.
---
paper_title: Near real time monitoring of biomass burning particulate emissions (PM2.5) across contiguous United States using multiple satellite instruments

paper_content:

Abstract Biomass burning is a major source of aerosols that affect air quality and the Earth's radiation budget. Current estimates of biomass burning emissions vary markedly due to uncertainties in biomass density, combustion efficiency, emission factor, and burned area. This study explores the modeling of biomass burning emissions using satellite-derived vegetative fuel loading, fuel moisture, and burned area across Contiguous United States (CONUS). The fuel loading is developed from Moderate-Resolution Imaging Spectroradiometer (MODIS) data including land cover type, vegetation continuous field, and monthly leaf area index. The weekly fuel moisture category is retrieved from AVHRR (Advanced Very High Resolution Radiometer) Global Vegetation Index (GVIx) data for the determination of fuel combustion efficiency and emission factor. The burned area is simulated using half-hourly fire sizes obtained from the GOES (Geostationary Operational Environmental Satellites) Wildfire Automated Biomass Burning Algorithm (WF_ABBA) fire product. By integrating all these parameters, quantities of PM2.5 (particulate mass for particles with diameter
---
paper_title: Deforestation dynamics and policy changes in Bolivia's post-neoliberal era

paper_content:

This work compares the effects of neoliberal and post-neoliberal land-use policies on forest cover along the Corredor Bioceanico of southeastern Bolivia to determine if rates of agriculturally driven forest clearance have changed since the Morales’ administration came to office in 2005. Satellite image analysis, supported by semi-structured interviews with farmers and representatives of key institutions, shows that deforestation for commercial agriculture in Santa Cruz continues and has increased in certain “hotspots”. Previous research has shown that the environmental effects of neoliberalism on forest cover are varied, but more broadly, reduced state intervention has meant less environmental regulation and greater deforestation, while strong government is better able to curtail deforestation. Although neoliberal policies triggered an unprecedented level of forest clearing in Bolivia, rates have generally continued to increase and can be indirectly linked to the administration's new agrarian reform and pro-environmental regulations. This trend is counterintuitive and stems from unanticipated responses such as deforestation through fire to prove productive use under the reform's socio-economic function requirements. Given increased regulation and enforcement of forest clearing and burning under Morales, in contrast to the neoliberal era, our analyses suggest that rates will continue to increase under the current political climate, which has further polarized the opposition in Santa Cruz.
---
paper_title: Fire Information for Resource Management System: Archiving and Distributing MODIS Active Fire Data

paper_content:

Technological advances have driven all aspects of Earth observation data, including improvements realized in sensor characteristics and capabilities, global data processing, near real-time monitoring, value-added products, and the distribution of global products. In particular, the growth of the World Wide Web is contributing to an increase in the global user base. The synergy of remote sensing, geographic information systems (GIS), Internet, and mobile phone technologies is revolutionizing the way in which satellite-derived information is archived and distributed to users. The Fire Information for Resource Management System (FIRMS), a NASA-funded application, is just one of many examples that illustrate the increasing ease with which Earth observation data are accessible to a broad range of users. This paper describes how the delivery of satellite-derived fire information has evolved over the last six years. By understanding user requirements and taking advantage of recent developments in areas such as information management, search, access, visualization, and enabling technologies, FIRMS has expanded the number and range of users that are able to access and utilize satellite-derived fire information. Specifically, we describe how satellite remote sensing and GIS technologies have been integrated to deliver MODIS active fire data to natural resource managers using Internet mapping services and customized e-mail alerts to users in more than 90 countries. We also describe how this web-based desktop application has been transitioned to a mobile service in South Africa to deliver fire information to field staff to warn of fires that may be potentially damaging to both natural resources and infrastructure.
---
paper_title: Remote Sensibilities: Discourses of Technology and the Making of Indonesia’s Natural Disaster

paper_content:

During the extended El Nin˜o drought of 1997–8, fires devastated Indonesia’s forests, creating a vast shroud of smoke that reached as far as mainland Southeast Asia. This article examines the interpretation of these fires — their causes, damages and solutions — by the Indonesian government, international donors, environmental activists and local farmers. It explores the contexts and consequences of these discourses of disaster, and specifically investigates the central role of remote technology — a ‘hegemonic’ representational tool, in some circumstances creatively appropriated to serve new democratic agendas. A narrow focus on remotely sensed data is not strictly a methodological but also a political choice, one which obscures alternative experiences of disaster and produces solutions that do not address long term social and political processes leading to the fires. What is missing from most current analyses of the fires, and from remote assessments in general, is a textured understanding of social landscapes and the role they play in creating fire hazards.
---
paper_title: Emission factors for open and domestic biomass burning for use in atmospheric models

paper_content:

Biomass burning (BB) is the second largest source of trace gases and the largest source of primary fine carbonaceous particles in the global troposphere. Many recent BB studies have provided new emission factor (EF) measurements. This is especially true for non-methane organic compounds (NMOC), which influence secondary organic aerosol (SOA) and ozone formation. New EF should improve regional to global BB emissions estimates and therefore, the input for atmospheric models. In this work we present an up-to-date, comprehensive tabulation of EF for known pyrogenic species based on measurements made in smoke that has cooled to ambient temperature, but not yet undergone significant photochemical processing. All EFs are converted to one standard form (g compound emitted per kg dry biomass burned) using the carbon mass balance method and they are categorized into 14 fuel or vegetation types. Biomass burning terminology is defined to promote consistency. We compile a large number of measurements of biomass consumption per unit area for important fire types and summarize several recent estimates of global biomass consumption by the major types of biomass burning. Post emission processes are discussed to provide a context for the emission factor concept within overall atmospheric chemistry and also highlight the potential for rapid changes relative to the scale of some models or remote sensing products. Recent work shows that individual biomass fires emit significantly more gas-phase NMOC than previously thought and that including additional NMOC can improve photochemical model performance. A detailed global estimate suggests that BB emits at least 400 Tg yr^(−1) of gas-phase NMOC, which is almost 3 times larger than most previous estimates. Selected recent results (e.g. measurements of HONO and the BB tracers HCN and CH_3CN) are highlighted and key areas requiring future research are briefly discussed.
---
paper_title: Biomass Burning as a Source of Atmospheric Gases CO, H2, N2O, NO, CH3Cl and COS

paper_content:

The potential importance of deforestation and biomass burning for the atmospheric CO2 cycle has received much attention and caused some controversy. Biomass burning can contribute extensively to the budgets of several gases which are important in atmospheric chemistry. In several cases the emission is comparable to the technological source. Most burning takes place in the tropics in the dry season and is caused by man’s activities. The potential importance of deforestation and biomass burning for the atmospheric CO2 cycle has received much attention and caused some controversy. In this article we will show the probable importance of biomass burning as a trace gas source, which is caused by man’s activities in the tropics. We used the results of our global biomass burning analysis to derive some rough estimates of the sources of the important atmospheric trace gases CO, H2, CH4, N2O, NOx (NO and NO2), COS and CH3Cl from the worldwide burning of biomass.
---
paper_title: Global Real‐time Fire Emission Estimates Based on Space‐borne Fire Radiative Power Observations

paper_content:

We present the first real‐time system for the estimation of global biomass burning emissions from several different satellite‐based fire radiative power (FRP) observations. The FRP products from the MODIS and SEVIRI instruments on Aqua, Terra, and Meteosat‐9 are combined by averaging all pixels with fire detection or just the potential of fire detection on a global grid with ∼125 km resolution. The total observed area per grid cell is used as a proxy for the accuracy of the estimation. Thus the different observations can be merged consistently and the advantage the high temporal sampling frequency of the geostationary observation is maintained while almost global coverage is achieved with the polar orbiting platforms. The system is being tested and validation is ongoing. As a first trial application, daily pyrogenic carbon monoxide emissions are used in the European GEMS project to produce 3‐day forecasts of the carbon monoxide plumes emitted by biomass burning. Some potential improvements of the method a...
---
paper_title: Annual carbon balance of Canada's forests during 1895–1996

paper_content:

This paper reports annual carbon (C) balance of Canada's forests during 1895-1996 estimated using the Integrated Terrestrial Ecosystem C-budget model (InTEC) [Chen et. al., this issue]. During 1895-1910, Canada's forests were small sources of 30±15 Tg C yr -1 due to large disturbances (forest fire, insect-induced mortality, and harvest) in late nineteenth century. The forests became large sinks of 170±85 Tg C yr -1 during 1930-1970, owing to forest regrowth in previously disturbed areas and growth stimulation by nondisturbance factors such as climate, atmospheric CO 2 concentration, and N deposition. In recent decades (1980-1996), Canada's forests have been moderate sinks of 50±25 Tg C yr -1 , as a result of a tradeoff between the negative effects of increased disturbances and positive effects of nondisturbance factors. The nondisturbance factors, in order of importance, are (1) atmospheric N deposition (measured by a national monitoring network), (2) net N mineralization and fixation (estimated from temperature and precipitation records), (3) growing season length increase (estimated from spring air temperature records), and (4) CO 2 fertilization (estimated from CO 2 records using a leaf-level photosynthesis model). The magnitudes of modeled nondisturbance effects are consistent with simulation results by the Carnegie-Ames-Stanford Approach (CASA) and are also in broad agreement with flux measurements above mature forest stands at several locations in Canada. Results for the disturbance effects agree with a previous study [Kurz and Apps, 1996]. The overall C balance from InTEC generally agrees with that derived from tree ring data [Auclair and Bedford, 1997] and from forest inventories. The combination of our result and that of Houghton et al. [1999] for the United States suggests that North America (> 15°N), was probably a C sink of 0.2-0.5 Pg C yr -1 during 1980s, much less than that of 1.7 Pg C yr -1 estimated by Fan et al. [1998] using an atmospheric inversion method.
---
paper_title: On the use of ATSR fire count data to estimate the seasonal and interannual variability of vegetation fire emissions

paper_content:

Biomass burning has long been recognised as an important source of trace gases and aerosols in the atmo- sphere. The burning of vegetation has a repeating seasonal pattern, but the intensity of burning and the exact localisa- tion of fires vary considerably from year to year. Recent studies have demonstrated the high interannual variability of the emissions that are associated with biomass burning. In this paper I present a methodology using active fire counts from the Along-Track Scanning Radiometer (ATSR) sensor on board the ERS-2 satellite to estimate the seasonal and in- terannual variability of global biomass burning emissions in the time period 1996-2000. From the ATSR data, I compute relative scaling factors of burning intensity for each month, which are then applied to a standard inventory for carbon monoxide emissions from biomass burning. The new, time- resolved inventory is evaluated using the few existing multi- year burned area observations on continental scales.
---
paper_title: Global carbon emissions from biomass burning in the 20th century

paper_content:

[1] We used a new, 100-year, 1 × 1° global fire map and a carbon cycle model (CASA) to provide a yearly gridded estimate of the temporal trend in carbon emissions due to wildfires through the 20th century. 2700–3325 Tg C y−1 burn at the end of the 20th century, compared to 1500–2700 Tg C y−1 at the beginning, with increasing uncertainty moving backward in time. There have been major changes in the regional distribution of emissions from fires, as a consequence of i) increased burning in tropical savannas and ii) a switch of emissions from temperate and boreal forests towards the tropics. The frequently-used assumption that pre-industrial emissions were 10% of present biomass burning is clearly inadequate, in terms of both the total amount and the spatial distribution of combustion.
---
paper_title: Airborne studies of particles and gases from forest fires

paper_content:

Airborne measurements have been made in the emissions from several prescribed (deliberate) forest fires in Western Washington State. Particle measurements in the size range of 0.01 to 60 fim diameter show a multimodal character with the majority of the mass contained in particles between 0.1 to 1 pm in diameter. A particle emission factor (mass of particles produced per unit mass of forest fuel consumed) of about 4% was deduced for one of the fires. In addition to expected emissions of nitrogen dioxide, some of the fires appeared to be substantial sources of ozone. The fires were negligible sources of nitric oxide and sulfur dioxide.
---
paper_title: Estimates of gross and net fluxes of carbon between the biosphere and the atmosphere from biomass burning

paper_content:

In order to estimate the production of charcoal and the atmospheric emissions of trace gases volatilized by burning we have estimated the global amounts of biomass which are affected by fires. We have roughly calculated annual gross burning rates ranging between about 5 Pg and 9 Pg (1 Pg = 1015 g) of dry matter (2–4 Pg C). In comparison, about 9–17 Pg of above-ground dry matter (4–8 Pg C) is exposed to fires, indicating a worldwide average burning efficiency of about 50%. The production of dead below-ground dry matter varies between 6–9 Pg per year. We have tentatively indicated the possibility of a large production of elemental carbon (0.5–1.7 Pg C/yr) due to the incomplete combustion of biomass to charcoal. This provides a sink for atmospheric CO2, which would have been particularly important during the past centuries. From meager statistical information and often ill-documented statements in the literature, it is extremely difficult to calculate the net carbon release rates to the atmosphere from the biomass changes which take place, especially in the tropics. All together, we calculate an overall effect lof the biosphere on the atmospheric carbon dioxide budget which may range between the possibilities of a net uptake or a net release of about 2 Pg C/yr. The release of CO2 to the atmosphere by deforestation projects may well be balanced by reforestation and by the production of charcoal. Better information is needed, however, to make these estimates more reliable.
---
paper_title: Emissions of gases and particles from biomass burning during the 20th century using satellite data and an historical reconstruction

paper_content:

Abstract A new dataset of emissions of trace gases and particles resulting from biomass burning has been developed for the historical and the recent period (1900–2005). The purpose of this work is to provide a consistent gridded emissions dataset of atmospheric chemical species from 1900 to 2005 for chemistry-climate simulations. The inventory is built in two steps. First, fire emissions are estimated for the recent period (1997–2005) using satellite products (GBA2000 burnt areas and ATSR fire hotspots); the temporal and spatial distribution of the CO2 emissions for the 1997–2005 period is estimated through a calibration of ATSR fire hotspots. The historical inventory, covering the 1900–2000 period on a decadal basis, is derived from the historical reconstruction of burned areas from Mouillot and Field (2005) . The historical emissions estimates are forced, for each main ecosystem, to agree with the recent inventory estimates, ensuring consistency between past and recent emissions. The methodology used for estimating the fire emissions is discussed, together with the time evolution of biomass burning emissions during the 20th century, first at the global scale and then for specific regions. The results are compared with the distributions provided by other inventories and results of inverse modeling studies.
---
paper_title: An assessment of vegetation fire in Africa (1981–1991): Burned areas, burned biomass, and atmospheric emissions

paper_content:

This paper presents the first published time series of burned area maps of Africa, covering an 8 year period, 1981–1983 and 1985–1991. These maps were derived from the analysis of the advanced very high resolution radiometer (AVHRR) global area coverage (GAC) images at 5 km resolution. The burned area maps for the period 1985–1991 were used with biomass density and burning efficiency figures, to estimate the quantity of burned biomass during this 6 year period. Emission factors were further used to estimate the trace gas and aerosol emissions produced by vegetation fires. Biomass density was estimated based on values found in the literature and on the accumulated normalized difference vegetation index (NDVI) as derived from the remote sensing images. Burning efficiency was assessed with a dryness index that was based on the relative greenness index (RGI), also derived from the NDVI. Average emission factors were retrieved from the literature. The uncertainties in the burned area, biomass density, combustion efficiency, and emission factors were considered, with a total error of 51% for the burned biomass and 58% for the emission estimates. The results obtained for the burned biomass in Africa were compared with other values found in the literature and showed values lower by a factor of 1.1–3.3. The annual burned biomass from vegetation fires in Africa on average was estimated between 704 and 2168 Tg . In the same way, the atmospheric emissions on average ranges are as follows: CO2 (990–3726 Tg), CO (40–151 Tg), CH4 (1.2–4.4 Tg), NOx (2.8–10.6 Tg), and PM (< 2.5 μm) (3.3–12.4Tg).
---
paper_title: Emission of trace gases and aerosols from biomass burning

paper_content:

A large body of information on emissions from the various types of biomass burning has been accumulated over the past decade, to a large extent as a result of International Geosphere-Biosphere Programme/International Global Atmospheric Chemistry research activities. Yet this information has not been readily accessible to the atmospheric chemistry community because it was scattered over a large number of publications and reported in numerous different units and reference systems. We have critically evaluated the presently available data and integrated these into a consistent format. On the basis of this analysis we present a set of emission factors for a large variety of species emitted from biomass fires. Where data were not available, we have proposed estimates based on appropriate extrapolation techniques. We have derived global estimates of pyrogenic emissions for important species emitted by the various types of biomass burning and compared our estimates with results from inverse modeling studies.
---
paper_title: Regional application of an ecosystem production model for studies of biogeochemistry in Brazilian Amazonia

paper_content:

The degree to which primary production, soil carbon, and trace gas fluxes in tropical forests of the Amazon are limited by moisture availability and other environmental factors was examined using an ecosystem modelling application for the country of Brazil. A regional geographical information system (GIS) serves as the data source of climate drivers, satellite images, land cover, and soil properties for input to the NASA Ames-CASA (Carnegie-Ames-Stanford Approach) model over a 8-km grid resolution. Simulation results lead us to hypothesize that net primary production (NPP) is limited by cloud interception of solar radiation over the humid north-western portion of the region. Peak annual rates for NPP of nearly 1.4 kg C m ‐2 year ‐1 are localized in the seasonally dry eastern Amazon in areas that we assume are primarily deep-rooted evergreen forest cover. Regional effects of forest conversion on NPP and soil carbon content are indicated in the model results, especially in seasonally dry areas. Comparison of model flux predictions along selected eco-climatic transects reveal moisture, soil, and land use controls on gradients of ecosystem production and soil trace gas emissions (CO2 ,N 2O, and NO). These results are used to formulate a series of research hypotheses for testing in the next phase of regional modelling, which includes recalibration of the light-use efficiency term in NASA-CASA using field measurements of NPP, and refinements of vegetation index and soil property (texture and potential rooting depth) maps for the region.
---
paper_title: Terrestrial ecosystem production: A process model based on global satellite and surface data

paper_content:

This paper presents a modeling approach aimed at seasonal resolution of global climatic and edaphic controls on patterns of terrestrial ecosystem production and soil microbial respiration. We use satellite imagery (Advanced Very High Resolution Radiometer and International Satellite Cloud Climatology Project solar radiation), along with historical climate (monthly temperature and precipitation) and soil attributes (texture, C and N contents) from global (1°) data sets as model inputs. The Carnegie-Ames-Stanford approach (CASA) Biosphere model runs on a monthly time interval to simulate seasonal patterns in net plant carbon fixation, biomass and nutrient allocation, litterfall, soil nitrogen mineralization, and microbial CO2 production. The model estimate of global terrestrial net primary production is 48 Pg C yr−1 with a maximum light use efficiency of 0.39 g C MJ−1PAR. Over 70% of terrestrial net production takes place between 30°N and 30°S latitude. Steady state pools of standing litter represent global storage of around 174 Pg C (94 and 80 Pg C in nonwoody and woody pools, respectively), whereas the pool of soil C in the top 0.3 m that is turning over on decadal time scales comprises 300 Pg C. Seasonal variations in atmospheric CO2 concentrations from three stations in the Geophysical Monitoring for Climate Change Flask Sampling Network correlate significantly with estimated net ecosystem production values averaged over 50°–80° N, 10°–30° N, and 0°–10° N.
---
paper_title: Carbon emissions from fires in tropical and subtropical ecosystems

paper_content:

Global carbon emissions from fires are difficult to quantify and have the potential to influence interannual variability and long-term trends in atmospheric CO2 concentrations. We used 4 years of Tropical Rainfall Measuring Mission (TRMM) Visible and Infrared Scanner (VIRS) satellite data and a biogeochemical model to assess spatial and temporal variability of carbon emissions from tropical fires. The TRMM satellite data extended between 38°N and 38°S and covered the period from 1998 to 2001. A relationship between TRMM fire counts and burned area was derived using estimates of burned area from other satellite fire products in Africa and Australia and reported burned areas from the United States. We modified the Carnegie-Ames-Stanford-Approach (CASA) biogeochemical model to account for both direct combustion losses and the decomposition from fire-induced mortality, using both TRMM and Sea-viewing Wide Field of view Sensor (SeaWiFS) satellite data as model drivers. Over the 1998-2001 period, we estimated that the sum of carbon emissions from tropical fires and fuel wood use was 2.6 Pg Cyr-1. An additional flux of 1.2 PgCyr-1 was released indirectly, as a result of decomposition of vegetation killed by fire but not combusted. The sum of direct and indirect carbon losses from fires represented 9% of tropical and subtropical net primary production (NPP). We found that including fire processes in the tropics substantially alters the seasonal cycle of net biome production by shifting carbon losses to months with low soil moisture and low rates of soil microbial respiration. Consequently, accounting for fires increases growing season net flux by ∼12% between 38°N and 38°S, with the greatest effect occurring in highly productive savanna regions.
---
paper_title: Biomass Burning Emissions: A Review of Models Using Remote-Sensing Data

paper_content:

The modification of climate and the atmosphere by anthropogenically produced ::: emissions is increasingly critical. Trace gas emissions and aerosols from biomass ::: burning represent a significant part of total gas emissions. It is estimated that the ::: total biomass amount consumed annually is 8680 Tg, with a release of 3500 Tg of ::: carbon in the form of carbon dioxide (CO2). From that amount, roughly 42% comes ::: from savanna fires, 23% from agricultural wastes, 17% from forests and another ::: 18% from wood fuels (Andreae, 1991).....
---
paper_title: Global carbon emissions from biomass burning in the 20th century

paper_content:

[1] We used a new, 100-year, 1 × 1° global fire map and a carbon cycle model (CASA) to provide a yearly gridded estimate of the temporal trend in carbon emissions due to wildfires through the 20th century. 2700–3325 Tg C y−1 burn at the end of the 20th century, compared to 1500–2700 Tg C y−1 at the beginning, with increasing uncertainty moving backward in time. There have been major changes in the regional distribution of emissions from fires, as a consequence of i) increased burning in tropical savannas and ii) a switch of emissions from temperate and boreal forests towards the tropics. The frequently-used assumption that pre-industrial emissions were 10% of present biomass burning is clearly inadequate, in terms of both the total amount and the spatial distribution of combustion.
---
paper_title: Diagnosing and assessing uncertainties of terrestrial ecosystem models in a multimodel ensemble experiment: 2. Carbon balance

paper_content:

This paper examines carbon stocks and their relative balance in terrestrial ecosystems simulated by Biome-BGC, LPJ, and CASA in an ensemble model experiment conducted using the Terrestrial Observation and Prediction System. We developed the Hierarchical Framework for Diagnosing Ecosystem Models to separate the simulated biogeochemistry into a cascade of functional tiers and examine their characteristics sequentially. The analyses indicate that the simulated biomass is usually two to three times higher in Biome-BGC than LPJ or CASA. Such a discrepancy is mainly induced by differences in model parameters and algorithms that regulate the rates of biomass turnover. The mean residence time of biomass in Biome-BGC is estimated to be 40–80 years in temperate/moist climate regions, while it mostly varies between 5 and 30 years in CASA and LPJ. A large range of values is also found in the simulated soil carbon. The mean residence time of soil carbon in Biome-BGC and LPJ is � 200 years in cold regions, which decreases rapidly with increases of temperature at a rate of � 10 yr1C � 1 . Because long-term soil carbon pool is not simulated in CASA, its corresponding mean residence time is only about 10–20 years and less sensitive to temperature. Another key factor that influences the carbon balance of the simulated ecosystem is disturbance caused by wildfire, for which the algorithms vary among the models. Because fire emissions are balanced by net ecosystem production (NEP) at steady states, magnitudes, and spatial patterns of NEP vary significantly as well. Slight carbon imbalance may be left by the spin-up algorithm of the models, which adds uncertainty to the estimated carbon sources or sinks. Although these results are only drawn on the tested model versions, the developed methodology has potential for other model exercises.
---
paper_title: Global net primary production: Combining ecology and remote sensing

paper_content:

Terrestrial net primary production (NPP) is sensitive to a number of controls, including aspects of climate, topography, soils, plant and microbial characteristics, disturbance, and anthropogenic impacts. Yet, at least at the global scale, models based on very different types and numbers of parameters yield similar results. Part of the reason for this is that the major NPP controls influence each other, resulting, under current conditions, in broad correlations among controls. NPP models that include richer suites of controlling parameters should be more sensitive to conditions that disrupt the broad correlations, but the current paucity of global data limits the power of complex models. Improved data sets will facilitate applications of complex models, but many of the critical data are very difficult to produce, especially for applications dealing with the past or future. It may be possible to overcome some of the challenges of data availability through increased understanding and modeling of ecological processes that adjust plant physiology and architecture in relation to resources. The CASA (Carnegie, Stanford, Ames Approach) model introduced by Potter et al. (1993) and expanded here uses a combination of ecological principles, satellite data, and surface data to predict terrestrial NPP on a monthly time step. CASA calculates NPP as a product of absorbed photosynthetically active radiation, APAR, and an efficiency of radiation use, ϵ. The underlying postulate is that some of the limitations on NPP appear in each. CASA estimates annual terrestrial NPP to be 48 Pg and the maximum efficiency of PAR utilization (ϵ∗) to be 0.39 g C MJ−1 PAR. Spatial and temporal variation in APAR is more than fivefold greater than variation in ϵ.
---
paper_title: GLC2000: a new approach to global land cover mapping from Earth observation data

paper_content:

A new global land cover database for the year 2000 (GLC2000) has been produced by an international partnership of 30 research groups coordinated by the European Commission's Joint Research Centre. The database contains two levels of land cover information—detailed, regionally optimized land cover legends for each continent and a less thematically detailed global legend that harmonizes regional legends into one consistent product. The land cover maps are all based on daily data from the VEGETATION sensor on‐board SPOT 4, though mapping of some regions involved use of data from other Earth observing sensors to resolve specific issues. Detailed legend definition, image classification and map quality assurance were carried out region by region. The global product was made through aggregation of these. The database is designed to serve users from science programmes, policy makers, environmental convention secretariats, non‐governmental organizations and development‐aid projects. The regional and global data ar...
---
paper_title: An approach to operational forest fire growth predictions for Canada

paper_content:

This paper presents an operational approach to predicting fire growth for wildland fires in Canada. The approach addresses data assimilation to provide predictions in a timely and efficient manner. Fuels and elevation grids, forecast weather, and active fire locations are entered into a fire-growth model; then predicted fire perimeters are mapped and presented on the web. The Moderate Resolution Imaging Spectroradiometer (MODIS) and the National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer (NOAA/AVHRR) satellite-based detection systems are used to detect current wildland fires (referred to as hotspots). For selected regions, fire-growth simulation environments are assembled. Fuel type data from several fire management agencies are available in grid format at a resolution of 100 m or less; in areas where such data are not available, a national fuels map based on Satellite Pour l’Observation de la Terre Vegetation sensor (SPOT VGT) land cover and forest inventory is used. Similarly, terrain data are available from a variety of sources. Current hotspots are used as ignition points while past hotspots are used to delineate area burned. Surface wind, temperature, and dew-point values (forecast by Environment Canada) are used to determine the fire weather conditions at the fire location. A case study of two large fires in Canada consisting of 54 fire simulation days is used to test these hypotheses.
---
paper_title: Representing a new MODIS consistent land surface in the Community Land Model (CLM 3.0)

paper_content:

[1] Recently a number of studies have found significant differences between Moderate Resolution Imaging Spectroradiometer (MODIS) land surface mapping and the land surface parameters of the Community Land Model (CLM) of the Community Climate System Model (CCSM). To address these differences in land surface description, we have developed new CLM 3.0 land surface parameters that reproduce the physical properties described in the MODIS land surface data while maintaining the multiple Plant Functional Type (PFT) canopy and herbaceous layer representation used in CLM. These new parameters prescribe crop distributions directly from historical crop mapping allowing cropping to be described in CLM for any year from 1700 to current day. The new model parameters are calculated at 0.05 degrees resolution so they can be aggregated and used over a wider range of model grid resolutions globally. Compared to the current CLM 3.0 parameters, the new parameters have an increase in bare soil fraction of 10% which is realized through reduced tree, shrub, and crop cover. The new parameters also have area average increases of 10% for leaf area index (LAI) and stem area index (SAI) values, with the largest increases in tropical forests. The new land surface parameters have strong repeatable impacts on the climate simulated in CCSM 3.0 with large improvements in surface albedo compared to MODIS values. In many cases the improvements in surface albedo directly resulted in improved simulation of precipitation and near-surface air temperature; however, for the most part the existing biases of CCSM 3.0 remained with the new parameters. Further analysis of changes in surface hydrology revealed that the increased LAI of the new parameters resulted in lower overall evapotranspiration with reduced precipitation in CCSM 3.0. This was an unexpected result given that other research into the impacts of vegetation change suggests that the new parameters should have the opposite impact. This suggests that while the new parameters significantly improve the climate simulated in CLM 3.0 and CCSM 3.0, the new surface parameters have limited success in rectifying surface hydrology biases that result from the parameterizations within the CLM 3.0.
---
paper_title: PLANT FUNCTIONAL TRAITS IN RELATION TO FIRE IN CROWN-FIRE ECOSYSTEMS

paper_content:

Disturbance is a dominant factor in many ecosystems, and the disturbance regime is likely to change over the next decades in response to land-use changes and global warming. We assume that predictions of vegetation dynamics can be made on the basis of a set of life-history traits that characterize the response of a species to disturbance. For crown-fire ecosystems, the main plant traits related to postfire persistence are the ability to resprout (persistence of individuals) and the ability to retain a persistent seed bank (persistence of populations). In this context, we asked (1) to what extent do different life- history traits co-occur with the ability to resprout and/or the ability to retain a persistent seed bank among differing ecosystems and (2) to what extent do combinations of fire- related traits (fire syndromes) change in a fire regime gradient? We explored these questions by reviewing the literature and analyzing databases compiled from different crown-fire ecosystems (mainly eastern Australia, California, and the Mediterranean basin). The review suggests that the pattern of correlation between the two basic postfire persistent traits and other plant traits varies between continents and ecosystems. From these results we predict, for instance, that not all resprouters respond in a similar way everywhere because the associated plant traits of resprouter species vary in different places. Thus, attempts to generalize predictions on the basis of the resprouting capacity may have limited power at a global scale. An example is presented for Australian heathlands. Considering the com- bination of persistence at individual (resprouting) and at population (seed bank) level, the predictive power at local scale was significantly increased.
---
paper_title: A classification of landscape fire succession models: spatial simulations of fire and vegetation dynamics �

paper_content:

A classification of spatial simulation models of fire and vegetation dynamics (landscape fire succession models or LFSMs) is presented. The classification was developed to provide a foundation for comparing models and to help identify the appropriate fire and vegetation processes and their simulation to include in coarse scale dynamic global vegetation models. Other uses include a decision tool for research and management applications and a vehicle to interpret differences between LFSMs. The classification is based on the four primary processes that influence fire and vegetation dynamics: fire ignition, fire spread, fire effects, and vegetation succession. Forty-four LFSMs that explicitly simulated the four processes were rated by the authors and the modelers on a scale from 0 to 10 for their inherent degree of stochasticity, complexity, and mechanism for each of the four processes. These ratings were then used to group LFSMs into similar classes using common ordination and clustering techniques. Another database was created to describe each LFSM using selected keywords for over 20 explanatory categories. This database and the ordination and clustering results were then used to create the final LFSM classification that contains 12 classes and a corresponding key. The database and analysis results were used to construct a second classification key so managers can pick the most appropriate model for their application based on computer resources, available modeling expertise, and management objective. Published by Elsevier B.V.
---
paper_title: Evaluation of ecosystem dynamics, plant geography and terrestrial carbon cycling in the LPJ dynamic global vegetation model

paper_content:

The Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ) combines process-based, large-scale representations of terrestrial vegetation dynamics and land-atmosphere carbon and water exchanges in a modular framework. Features include feedback through canopy conductance between photosynthesis and transpiration and interactive coupling between these 'fast' processes and other ecosystem processes including resource competition, tissue turnover, population dynamics, soil organic matter and litter dynamics and fire disturbance. Ten plants functional types (PFTs) are differentiated by physiological, morphological, phenological, bioclimatic and fire-response attributes. Resource competition and differential responses to fire between PFTs influence their relative fractional cover from year to year. Photosynthesis, evapotranspiration and soil water dynamics are modelled on a daily time step, while vegetation structure and PFT population densities are updated annually. Simulations have been made over the industrial period both for specific sites where field measurements were available for model evaluation, and globally on a 0.5degrees x 0.5degrees grid. Modelled vegetation patterns are consistent with observations, including remotely sensed vegetation structure and phenology. Seasonal cycles of net ecosystem exchange and soil moisture compare well with local measurements. Global carbon exchange fields used as input to an atmospheric tracer transport model (TM2) provided a good fit to observed seasonal cycles of CO2 concentration at all latitudes. Simulated inter-annual variability of the global terrestrial carbon balance is in phase with and comparable in amplitude to observed variability in the growth rate of atmospheric CO2 . Global terrestrial carbon and water cycle parameters (pool sizes and fluxes) lie within their accepted ranges. The model is being used to study past, present and future terrestrial ecosystem dynamics, biochemical and biophysical interactions between ecosystems and the atmosphere, and as a component of coupled Earth system models.
---
paper_title: A spatial comparison of four satellite derived 1 km global land cover datasets

paper_content:

Abstract Global change issues are high on the current international political agenda. A variety of global protocols and conventions have been established aimed at mitigating global environmental risks. A system for monitoring, evaluation and compliance of these international agreements is needed, with each component requiring comprehensive analytical work based on consistent datasets. Consequently, scientists and policymakers have put faith in earth observation data for improved global analysis. Land cover provides in many aspects the foundation for environmental monitoring [FAO, 2002a. Proceedings of the FAO/UNEP Expert Consultation on Strategies for Global Land Cover Mapping and Monitoring. FAO, Rome, Italy, 38 pp.]. Despite the significance of land cover as an environmental variable, our knowledge of land cover and its dynamics is poor [Foody, G.M., 2002. Status of land cover classification accuracy assessment. Rem. Sens. Environ. 80, 185–201]. This study compares four satellite derived 1 km land cover datasets freely available from the internet and in wide use among the scientific community. Our analysis shows that while these datasets have in many cases reasonable agreement at a global level in terms of total area and general spatial pattern, there is limited agreement on the spatial distribution of the individual land classes. If global datasets are used at a continental or regional level, agreement in many cases decreases significantly. Reasons for these differences are many—ranging from the classes and thresholds applied, time of data collection, sensor type, classification techniques, use of in situ data, etc., and make comparison difficult. Results of studies based on global land cover datasets are likely influenced by the dataset chosen. Scientists and policymakers should be made aware of the inherent limitations in using current global land cover datasets, and would be wise to utilise multiple datasets for comparison.
---
paper_title: Modelling the effects of landscape fuel treatments on fire growth and behaviour in a Mediterranean landscape (eastern Spain)

paper_content:

The number of large fires increased in the 1970s in the Valencia region (eastern Spain), as in most northern Mediterranean countries, owing to the fuel accumulation that affected large areas as a consequence of an intensive land abandonment. The Ayora site (Valencia province) was affected by a large fire in July 1979. We parameterised the fire growth model FARSITE for the 1979 fire conditions using remote sensing-derived fuel cartography. We simulated different fuel scenarios to study the interactions between fuel spatial distribution and fire characteristics (area burned, rate of spread and fireline intensity). We then tested the effectiveness of several firebreak networks on fire spread control. Simulations showed that fire propagation and behaviour were greatly influenced by fuel spatial distribution. The fragmentation of large dense shrubland areas through the introduction of wooded patches strongly reduced fire size, generally slowing fire and limiting fireline intensity. Both the introduction of forest corridors connecting woodlands and the promotion of complex shapes for wooded patches decreased the area burned. Firebreak networks were always very effective in reducing fire size and their effect was enhanced in appropriate fuel-altered scenarios. Most firebreak alternatives, however, did not reduce either rate of fire spread or fireline intensity.
---
paper_title: Modeling and sensitivity analysis of fire emissions in southern Africa during SAFARI 2000

paper_content:

This paper uses three recently generated southern African satellite burned area products for the month of September 2000 in a sensitivity study of regional biomass burning emissions for a number of trace gases and particulates. Differences in the extent and location of areas burned among products generated from Moderate Resolution Imaging Spectroradiometer (MODIS), Systeme Pour l'Observation de la Terre (SPOT-VEGETATION), and Along Track Scanning Radiometer (ATSR-2) data are significant and result in different emissions estimates for woodland and grassland land cover types. Due to the different emission profiles in woodlands and grasslands, favoring relatively more products of incomplete combustion in woodlands compared with products of complete combustion in grasslands in the late dry season, these changes are not proportional to the differences in the burned area amounts. The importance of accurate burned area information not just in terms of the total area but also in terms of its spatial distribution becomes apparent from our modeling results. This paper highlights the urgent need for satellite data producers to provide accuracy assessments associated with satellite-derived products. Preferably, these accuracy data will be spatially explicit, or defined in a way that can be applied in a spatially explicit modeling context, to enable emissions uncertainties to be defined with respect to different landscape units in support of greenhouse gas emissions reporting.
---
paper_title: A focus group study of factors that promote and constrain the use of satellite-derived fire products by resource managers in southern Africa.

paper_content:

Semi-structured focus group interviews were employed to examine factors that affect the likelihood that resource managers in southern Africa will use information on vegetation fires provided by two satellite-derived products: an active fire product and a burned area product. The two products are updated regularly and aim to deliver the state-of-the-art in the global monitoring of fires from satellite remote-sensing. Both products are derived from data transmitted by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors carried onboard NASA's Aqua and Terra satellites. The active fire product can be accessed for free via the internet and on media by users working anywhere in the world; the burned area product will be accessible in a similar manner in 2006. The MODIS fire products provide systematic, near-global coverage and are freely available; as such, they give resource managers new opportunities to obtain or supplement information they need to manage vegetation fires effectively. However, the availability of these products does not mean that resource managers will use them, and many other factors are involved. To understand factors that affect whether southern African resource managers will use the two products, two focus groups were held with members of the Southern African Fire Network (SAFNet) in Malawi, Africa, August 2004. Analysis of the group discussions reveals a number of factors that influence whether they will use the products. The qualitative, in depth nature of the group discussions revealed 12 main factors that influence product use; not least the low international internet bandwidths for African countries outside of South Africa. Analysis of the group discussions also suggests how the uptake of MODIS fire products by resource managers in southern Africa might be enhanced by affecting specific changes to how MODIS products are packaged and delivered.
---
paper_title: Burnt area detection at global scale using ATSR‐2: The GLOBSCAR products and their qualification

paper_content:

[1] Quantifying the contribution of biomass burning to the global distribution of emissions of carbon into the atmosphere requires knowledge of the area burnt. The GLOBSCAR project was initiated in 2001 as part of the European Space Agency (ESA) Data User Programme, with the objective of producing global incremental monthly maps of burnt areas, using daytime data from year 2000 of the Along Track Scanning Radiometer (ATSR-2) instrument onboard the ESA ERS-2 satellite. The processing system combines the use of two algorithms representing different approaches to burnt area detection. The K1 algorithm is a contextual algorithm based on the geometrical characteristics of the burnt pixels in the near-infrared (NIR, 0.87 microns)/thermal infrared (TIR, 11 microns) space, while the E1 algorithm consists of a series of fixed threshold tests applied to the data using information from four different spectral channels. The GLOBSCAR products are available from the GeoSuccess Web site (http://www.geosuccess.net) in ASCII and vector format. The products were validated using a variety of qualitative and quantitative tests against other field and remote sensing data. The GLOBSCAR results are presented per region and are compared to available statistics and other remote sensing products such as the ATSR-2 World Fire Atlas (WFA) and the Global Burnt Area product derived from SPOT/VEGETATION (GBA-2000). The potential and limitations of the GLOBSCAR products are then discussed. It is concluded that while the GLOBSCAR products represent a definite progress toward a better quantification of the areas burnt annually at the larger scales, coordinated improvements in remote sensing products are needed in order to better address the requirements of the user community. Future activities include the consolidation of the results through further qualification and the development of a multiyear multisensor product building upon the experience gained from both GLOBSCAR and GBA-2000 projects.
---
paper_title: Validation analyses of an operational fire monitoring product: The Hazard Mapping System

paper_content:

Vegetation fires are becoming increasingly important especially in regions where the proximity to urban areas can result in large populations being directly impacted by such events. During emergency situations, accurate fire location data becomes crucial to assess the affected areas as well as to track smoke plumes and delineate evacuation plans. In this study, the performance of the NOAA/NESDIS Hazard Mapping System (HMS) is evaluated. The system combines automated and analyst-made fire detections to monitor fires across the conterminous United States. Using 30-m-spatial-resolution ASTER imagery as the main instantaneous validation data, commission and omission error estimates are reported for a subset of HMS automated and analyst-based fire pixels derived from the Terra MODIS and GOES data.
---
paper_title: Global estimation of burned area using MODIS active fire observations

paper_content:

We present a method for estimating monthly burned area globally at 1 spatial resolution using Terra MODIS data and ancillary vegetation cover information. Us- ing regression trees constructed for 14 different global re- gions, MODIS active fire observations were calibrated to burned area estimates derived from 500-m MODIS imagery based on the assumption that burned area is proportional to counts of fire pixels. Unlike earlier methods, we al- low the constant of proportionality to vary as a function of tree and herbaceous vegetation cover, and the mean size of monthly cumulative fire-pixel clusters. In areas undergoing active deforestation, we implemented a subsequent correc- tion based on tree cover information and a simple measure of fire persistence. Regions showing good agreement be- tween predicted and observed burned area included Boreal Asia, Central Asia, Europe, and Temperate North Amer- ica, where the estimates produced by the regression trees were relatively accurate and precise. Poorest agreement was found for southern-hemisphere South America, where pre- dicted values of burned area are both inaccurate and im- precise; this is most likely a consequence of multiple fac- tors that include extremely persistent cloud cover, and lower quality of the 500-m burned area maps used for calibration. Application of our approach to the nine remaining regions yielded comparatively accurate, but less precise, estimates of monthly burned area. We applied the regional regres- sion trees to the entire archive of Terra MODIS fire data to produce a monthly global burned area data set spanning late 2000 through mid-2005. Annual totals derived from this approach showed good agreement with independent annual estimates available for nine Canadian provinces, the United States, and Russia. With our data set we estimate the global
---
paper_title: METHOD TO IDENTIFY FOREST FIRE BASED ON SMOKE PLUMES MASK BY USING MODIS DATA

paper_content:

Due to the poor regional adaptability of MODIS fire detection algorithm version 4,an improved method based on adjusted thresholds for tropical rainforest fire and smoke plume mask contextual analyse was applied in tropical rainforest.Smoke plume is propitious to enhance the identifiability of forest fire.Adjusted thresholds can improve the sensitivity of fire detection.According to the characteristic of tropical rainforest,for smoke plume pixels and non smoke plume pixels,the thresholds of potential fire pixels were adjusted to be 295K and 306 K,respectively.Smoke plume mask can delineate the scope of background pixels and add some constraints to contextual analyse.This can reduce the noise caused by low threshold.Two methods were compared and they were proven to be validated by using forest fire ground data.The improved algorithm has higher sensitivity for small fires in tropical rainforest especially for fires detected at large scan angles,and it increases the ability and accuracy to detect fire spots on regional scale.
---
paper_title: Detection rates of the MODIS active fire product in the United States

paper_content:

MODIS active fire data offer new information about global fire patterns. However, uncertainties in detection rates can render satellite-derived fire statistics difficult to interpret. We evaluated the MODIS 1 km daily active fire product to quantify detection rates for both Terra and Aqua MODIS sensors, examined how cloud cover and fire size affected detection rates, and estimated how detection rates varied across the United States. MODIS active fire detections were compared to 361 reference fires (≥ 18 ha) that had been delineated using pre- and post-fire Landsat imagery. Reference fires were considered detected if at least one MODIS active fire pixel occurred within 1 km of the edge of the fire. When active fire data from both Aqua and Terra were combined, 82% of all reference fires were found, but detection rates were less for Aqua and Terra individually (73% and 66% respectively). Fires not detected generally had more cloudy days, but not when the Aqua data were considered exclusively. MODIS detection rates decreased with fire size, and the size at which 50% of all fires were detected was 105 ha when combining Aqua and Terra (195 ha for Aqua and 334 ha for Terra alone). Across the United States, detection rates were greatest in the West, lower in the Great Plains, and lowest in the East. The MODIS active fire product captures large fires in the U.S. well, but may under-represent fires in areas with frequent cloud cover or rapidly burning, small, and low-intensity fires. We recommend that users of the MODIS active fire data perform individual validations to ensure that all relevant fires are included.
---
paper_title: A pragmatic assessment of the usefulness of the MODIS (Terra and Aqua) 1-km active fire (MOD14A2 and MYD14A2) products for mapping fires in the fynbos biome

paper_content:

The moderate resolution imaging spectroradiometer (MODIS) fire-affected area data are not currently available for download by the public; therefore, 1-km pixel MODIS active fire data (MOD14A2 and MYD14A2) were assessed as a potential source of fire history data for the fynbos biome. These data mapped between 60.1 and 65.7% of the area within fire boundaries mapped by reserve managers between July 2002 and April 2005. These results should not be taken as a negative reflection on the MODIS team, as active fires do not aim to map fire-affected area. Rather this exercise has helped identify specific limitations in the fynbos, which will provide insight into the fine-tuning of other MODIS fire products for use in the fynbos. Limitations are likely to be primarily due to sun-glint around coastlines; topographic shadows; highly reflective, light soils exposed after a fire; partial burning of pixels; patchy and irregular-shaped fires; and large pixel size. The MODIS active fire data are not sufficient for the purposes of developing a 4-year fire history of the fynbos. The publication of the 500-m MODIS fire-affected area data is eagerly anticipated as a solution.
---
paper_title: Strategies for the fusion of satellite fire radiative power with burned area data for fire radiative energy derivation

paper_content:

[1] Instantaneous estimates of the power released by a fire (Fire Radiative Power, FRP) are available with satellite active fire detection products. Integrating FRP in time provides an estimate of the total energy released (Fire Radiative Energy, FRE), which can be converted into burned biomass estimates needed by the atmospheric emissions modeling community. While straightforward in theory, the integration of FRP in time and space is affected by temporal and spatial undersampling imposed by the satellite sensing and orbit geometry, clouds, and active fire product omission errors. Combination of active fire FRP estimates with independently derived burned area maps provides the potential for improved and spatially explicit estimates of FRE and biomass burned. In the present work, strategies for the temporal interpolation of FRP data and for the spatial extrapolation of FRE across the burn are proposed and, as a study case, applied to an extensive grassland fire that burned for 40 days in northern Australia. The fusion of FRP estimates derived from MODIS Terra and Aqua active fire detections with the MODIS burned area product is considered, although other polar orbiting and geostationary satellite fire products could be used. Intercomparison of FRE estimated over the MODIS mapped burned area using Terra, Aqua, and Terra-Aqua combined FRP data highlights the sensitivity of FRE estimation to satellite sampling. Despite this sensitivity, FRE biomass burned estimates derived from MODIS burned area and Terra and Aqua FRP data are within 30% of regional literature estimates, suggesting that this fusion approach is a fruitful avenue for future research and validation.
---
paper_title: Multi-temporal active-fire based burn scar detection algorithm

paper_content:

A multi-temporal burn scar detection algorithm designed for global application is described and demonstrated using 24-daily AVHRR images of an area of savanna burning near the Okavango Delta, Southern Africa. Thealgorithm is computationally simple, does not use fixed thresholds except to detect saturated AVHRR pixels, and incorporates a recent active-fire detection algorithm. The algorithm provides the basis for operational burn scar monitoring using the AVHRR and MODIS.
---
paper_title: Fire Information for Resource Management System: Archiving and Distributing MODIS Active Fire Data

paper_content:

Technological advances have driven all aspects of Earth observation data, including improvements realized in sensor characteristics and capabilities, global data processing, near real-time monitoring, value-added products, and the distribution of global products. In particular, the growth of the World Wide Web is contributing to an increase in the global user base. The synergy of remote sensing, geographic information systems (GIS), Internet, and mobile phone technologies is revolutionizing the way in which satellite-derived information is archived and distributed to users. The Fire Information for Resource Management System (FIRMS), a NASA-funded application, is just one of many examples that illustrate the increasing ease with which Earth observation data are accessible to a broad range of users. This paper describes how the delivery of satellite-derived fire information has evolved over the last six years. By understanding user requirements and taking advantage of recent developments in areas such as information management, search, access, visualization, and enabling technologies, FIRMS has expanded the number and range of users that are able to access and utilize satellite-derived fire information. Specifically, we describe how satellite remote sensing and GIS technologies have been integrated to deliver MODIS active fire data to natural resource managers using Internet mapping services and customized e-mail alerts to users in more than 90 countries. We also describe how this web-based desktop application has been transitioned to a mobile service in South Africa to deliver fire information to field staff to warn of fires that may be potentially damaging to both natural resources and infrastructure.
---
paper_title: Detection of Active Wildland Fires Using Multitemporal MODIS Images

paper_content:

The fire fractional area and radiances at 4 and 11 ¿m of active fires in the boreal forests in Siberia and Mongolia were estimated using Advanced Spaceborne Thermal Emission and Reflection Radiometer images. In addition, a stochastic fire model was constructed. The efficiency of a biband threshold method used for detecting active fires on the basis of the thermal anomaly obtained from multitemporal Moderate Resolution Imaging Spectroradiometer (MODIS) images was evaluated using the stochastic fire model. The simulation results of fire detection indicated that the aforementioned method accurately detected 80% of the fire pixels with false alarms that were less than 2 x 10-5 when the radiances of the nonfire pixels at 4 and 11 ¿m were estimated using past MODIS images with a standard deviation (SD) of 1 K. The analyses also indicated that, in order to obtain fewer errors than those obtained using the conventional contextual algorithm (MOD14) from the objective area (omission errors that are less than 62% and commission errors that are less than 2 x 10-5), it is essential to carry out the nonfire radiance estimation using past images with an SD of less than 3 K. During an actual application of the multitemporal method to several fire cases, fewer errors occurred than those that occurred using MOD14.
---
paper_title: Multisource Data Integration for Fire Risk Management: The Local Test of a Global Approach

paper_content:

In this letter, we propose an algorithm to detect the presence of forest fires using data from both geostationary and polar-orbiting satellites. The very frequent acquisitions of the Spinning Enhanced Visible and Infrared Imager radiometer placed onboard the Meteosat Second Generation-9 satellite are used as main source for the algorithm, while the MEdium Resolution Imaging Spectrometer global vegetation index and the Advanced Along-Track Scanning Radiometer measurements are used to enhance the reliability of the detection. The problem is approached in a ?global? way, providing the basis for an automated system that is not dependent on the local area properties. In cooperation with the Centre de Suivi E?cologique (Dakar, Senegal), the proposed algorithm was implemented in a ?Multisource Fire Risk Management System? for the Senegal area, as briefly described in this letter. A field campaign of one week was carried out in order to perform a validation of the system's detections, showing a good agreement with the fire coordinates measured on the ground. Furthermore, a consistency check was performed using data from the Moderate Resolution Imaging Spectroradiometer (MODIS) Rapid Response System, showing that more than 76% of high-confidence MODIS events are detected by the algorithm.
---
paper_title: Using multiple endmember spectral mixture analysis to retrieve subpixel fire properties from MODIS

paper_content:

Abstract The Moderate-Resolution Imaging Spectroradiometer (MODIS) sensors on NASA's Terra and Aqua satellites image most of the Earth multiple times each day, providing useful data on fires that cannot be practically acquired using other means. Unfortunately, current fire products from MODIS and other sensors leave large uncertainties in measurements of fire sizes and temperatures, which strongly influence how fires spread, the amount and chemistry of their gas and aerosol emissions, and their impacts on ecosystems. In this study, we use multiple endmember spectral mixture analysis (MESMA) to retrieve subpixel fire sizes and temperatures from MODIS, possibly overcoming some limitations of existing methods for characterizing fire intensities such as estimating the fire radiative power (FRP). MESMA is evaluated using data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) to assess the performance of FRP and MESMA retrievals of fire properties from a simultaneously acquired MODIS image, for a complex of fires in Ukraine from August 21, 2002. The MESMA retrievals of fire size described in this paper show a slightly stronger correlation than FRP does to fire pixel counts from the coincident ASTER image. Prior to this work, few studies, if any, had used MESMA for retrieving fire properties from a broad-band sensor like MODIS, or compared MESMA to higher-resolution fire data or other measures of fire properties like FRP. In the future, MESMA retrievals could be useful for fire spread modeling and forecasting, reducing hazards that fires pose to property and health, and enhancing scientific understanding of fires and their effects on ecosystems and atmospheric composition.
---
paper_title: Identifying biomass burned patches of agriculture residue using satellite remote sensing data

paper_content:

The combine harvesting technology which has become common in the rice-wheat system in India leaves behind large quantities of straw in the field for open residue burning, and Punjab is one such region where this is regularly happening. This becomes a source for the emission of trace gases, resulting in perturbations to regional atmospheric chemistry. The study attempts to estimate district-wise burned area from agriculture residue burning. The feasibility of using low resolution (MODIS) and moderate resolution (AWiFS) satellite data for estimation of burned areas is shown. It utilizes thermal channels of MODIS and knowledge-based approach for AWiFS data for burned area estimation. A hybrid contextual test-fire detection and tentative-fire detection algorithm for satellite thermal images has been followed to identify the fire pixels over the region. The algorithm essentially treats fire pixels as anomalies in images and can be considered a special case of the more general clutter or background suppression problem. It utilizes the local background around a potential fire pixel, and discriminates fire pixels and avoids the false alarm. It incorporates the statistical properties of individual bands and requires the manual setting of multiple thresholds. Also, a decision-tree classification based on See5 algorithm is applied to AWiFS data. When combined with image classification using a machine learning decision tree (See5) classification, it gives high accuracy. The study compares the estimated burned area over the region using the two algorithms.
---
paper_title: An active-fire based burned area mapping algorithm for the MODIS sensor

paper_content:

We present an automated method for mapping burned areas using 500-m Moderate Resolution Imaging Spectroradiometer (MODIS) imagery coupled with 1-km MODIS active fire observations. The algorithm applies dynamic thresholds to composite imagery generated from a burn-sensitive vegetation index and a measure of temporal texture. Cumulative active fire maps are used to guide the selection of burned and unburned training samples. An accuracy assessment for three geographically diverse regions (central Siberia, the western United States, and southern Africa) was performed using high resolution burned area maps derived from Landsat imagery. Mapped burned areas were accurate to within approximately 10% in all regions except the high-tree-cover sub-region of southern Africa, where the MODIS burn maps underestimated the area burned by 41%. We estimate the minimum detectable burn size for reliable detection by our algorithm to be on the order of 120 ha.
---
paper_title: Burnt area estimation for the year 2005 in Borneo using multi-resolution satellite imagery

paper_content:

Humid tropical South-East Asia suffers significant yearly biomass burning. This paper evaluates and compares the results of medium-resolution (MODIS) burnt area mapping and hotspot-based assessment of fire affected areas in Borneo in 2005, using field observations and high resolution Landsat ETM+ data as reference. Based on burnt area mapping, over 600 000 ha burnt in large-scale vegetation fires. Approximately 90% of this burning took place in degraded ecosystems and was related to agricultural land clearing activities or logged over forests. The estimation based on active fire detection (hotspots) resulted in a total burnt area of more than 1.1 million hectares. The reason for this significant difference was that small scale shifting cultivation fires could not be detected in MODIS images. These results indicate that a combination of both methods is required to reliably assess burnt areas in Borneo using medium-resolution MODIS satellite imagery.
---
paper_title: Vegetation burning in the year 2000: Global burned area estimates from SPOT VEGETATION data

paper_content:

[1] The scientific community interested in atmospheric chemistry, gas emissions from vegetation fires, and carbon cycling is currently demanding information on the extent and timing of biomass burning at the global scale. In fact, the area and type of vegetation that is burned on a monthly or annual basis are two of the parameters that provide the greatest uncertainty in the calculation of gas and aerosol emissions and burned biomass. To address this need, an inventory of burned areas at monthly time periods for the year 2000 at a resolution of 1 km2 has been produced using satellite data and has been made freely available to the scientific community. In this paper, estimates of burned area and number of burn scars for four broad vegetation classes and reported at the country level for the year 2000 are presented using data taken from the inventory. Over 3.5 million km2 of burned areas were detected in the year 2000, of which approximately 80% occurred in areas described as woodlands and shrublands. Approximately 17% of the burned area occurred in grasslands and croplands, the remaining 3% occurred in forests. Almost 600,000 separate burn scars were detected. Descriptions of vegetation burning activity are given for ten regions. Finally, monthly burned area estimates are presented for the Central African Republic to illustrate the usefulness of these data for understanding, monitoring and managing vegetation burning activities.
---
paper_title: Estimating biomass consumed from fire using MODIS FRE

paper_content:

[1] Biomass burning is an important global phenomenon impacting atmospheric composition. Application of satellite based measures of fire radiative energy (FRE) has been shown to be effective for estimating biomass consumed, which can then be used to estimate gas and aerosol emissions. However, application of FRE has been limited in both temporal and spatial scale. In this paper we offer a methodology to estimate FRE globally for 2001–2007 at monthly time steps using MODIS. Accuracy assessment shows that our FRE estimates are precise (R2 = 0.85), but may be underestimated. Global estimates of FRE show that Africa and South America dominate biomass burning, accounting for nearly 70% of the annual FRE generated. Applying FRE-based combustion factors to Africa yields an annual average biomass burned of 716–881 Tg of dry matter (DM). Comparison with the GFEDv2 biomass burned estimates shows large annual differences suggesting significant uncertainty remains in emission estimates.
---
paper_title: Strategies for the fusion of satellite fire radiative power with burned area data for fire radiative energy derivation

paper_content:

[1] Instantaneous estimates of the power released by a fire (Fire Radiative Power, FRP) are available with satellite active fire detection products. Integrating FRP in time provides an estimate of the total energy released (Fire Radiative Energy, FRE), which can be converted into burned biomass estimates needed by the atmospheric emissions modeling community. While straightforward in theory, the integration of FRP in time and space is affected by temporal and spatial undersampling imposed by the satellite sensing and orbit geometry, clouds, and active fire product omission errors. Combination of active fire FRP estimates with independently derived burned area maps provides the potential for improved and spatially explicit estimates of FRE and biomass burned. In the present work, strategies for the temporal interpolation of FRP data and for the spatial extrapolation of FRE across the burn are proposed and, as a study case, applied to an extensive grassland fire that burned for 40 days in northern Australia. The fusion of FRP estimates derived from MODIS Terra and Aqua active fire detections with the MODIS burned area product is considered, although other polar orbiting and geostationary satellite fire products could be used. Intercomparison of FRE estimated over the MODIS mapped burned area using Terra, Aqua, and Terra-Aqua combined FRP data highlights the sensitivity of FRE estimation to satellite sampling. Despite this sensitivity, FRE biomass burned estimates derived from MODIS burned area and Terra and Aqua FRP data are within 30% of regional literature estimates, suggesting that this fusion approach is a fruitful avenue for future research and validation.
---
paper_title: Burned-Area Mapping of the Serengeti–Mara Region Using MODIS Reflectance Data

paper_content:

Fire is a key factor for vegetation structure and ecosystem functioning in the Serengeti-Mara region in East Africa. However, there is a lack of accurate and consistent information on fires. We developed an algorithm for mapping burned areas in the wider Serengeti-Mara region from remote-sensing data. The algorithm is automated and, once trained for one year, runs independently for all years. It uses daily measurements of red and near-infrared (NIR) reflectance acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor at a spatial resolution of 250 m. The MODIS time series was first converted to ten-day minimum NIR composites. Each composite was then classified into new and old burned areas, by thresholding burned-area index and temporal difference of NIR reflectances. The algorithm adjusts detection thresholds dynamically using measures related to atmospheric and vegetation conditions. Having trained the algorithm once on 2003 data, it was applied to MODIS data from April 21, 2000 to November 10, 2005. Accuracy was improved by size- and location-sensitive filters. Overall accuracy was 90.3% as determined from Advanced Spaceborne Thermal Emission and Reflection Radiometer satellite imagery from 2005 and 87.1% as determined using field data from 2005. The algorithm holds the potential to be applied to other savanna areas. This letter provides a reliable product useful for future investigations of fire ecology and fire management
---
paper_title: An active-fire based burned area mapping algorithm for the MODIS sensor

paper_content:

We present an automated method for mapping burned areas using 500-m Moderate Resolution Imaging Spectroradiometer (MODIS) imagery coupled with 1-km MODIS active fire observations. The algorithm applies dynamic thresholds to composite imagery generated from a burn-sensitive vegetation index and a measure of temporal texture. Cumulative active fire maps are used to guide the selection of burned and unburned training samples. An accuracy assessment for three geographically diverse regions (central Siberia, the western United States, and southern Africa) was performed using high resolution burned area maps derived from Landsat imagery. Mapped burned areas were accurate to within approximately 10% in all regions except the high-tree-cover sub-region of southern Africa, where the MODIS burn maps underestimated the area burned by 41%. We estimate the minimum detectable burn size for reliable detection by our algorithm to be on the order of 120 ha.
---
paper_title: The utility of satellite fire product accuracy Information-perspectives and recommendations from the Southern Africa fire network

paper_content:

This correspondence gives Southern Africa Fire Network (SAFNet) perspectives on the utility of satellite fire product accuracy information, drawing on two main sources: insights gained during SAFNet's six years of working together, and relevant findings from a SAFNet focus group study that explored factors that promote and constrain the use of the MODIS fire products. In giving this perspective, we comment on the approach and findings of recent fire product validation articles, including the two contained in this special issue. We recommend five ways that validation activities might be made more relevant to users and better connect producers of remotely sensed products to users in order to communicate satellite fire product accuracy information more effectively
---
paper_title: A review of global satellite-derived snow products

paper_content:

Abstract Snow cover over the Northern Hemisphere plays a crucial role in the Earth’s hydrology and surface energy balance, and modulates feedbacks that control variations of global climate. While many of these variations are associated with exchanges of energy and mass between the land surface and the atmosphere, other expected changes are likely to propagate downstream and affect oceanic processes in coastal zones. For example, a large component of the freshwater flux into the Arctic Ocean comes from snow melt. The timing and magnitude of this flux affects biological and thermodynamic processes in the Arctic Ocean, and potentially across the globe through their impact on North Atlantic Deep Water formation. Several recent global remotely sensed products provide information at unprecedented temporal, spatial, and spectral resolutions. In this article we review the theoretical underpinnings and characteristics of three key products. We also demonstrate the seasonal and spatial patterns of agreement and disagreement amongst them, and discuss current and future directions in their application and development. Though there is general agreement amongst these products, there can be disagreement over certain geographic regions and under conditions of ephemeral, patchy and melting snow.
---
paper_title: Terrestrial ecosystems from space: a review of earth observation products for macroecology applications

paper_content:

Aim Earth observation (EO) products are a valuable alternative to spectral vegetation indices. We discuss the availability of EO products for analysing patterns in macroecology, particularly related to vegetation, on a range of spatial and temporal scales. Location Global. Methods We discuss four groups of EO products: land cover/cover change, vegetation structure and ecosystem productivity, fire detection, and digital elevation models. We address important practical issues arising from their use, such as assumptions underlying product generation, product accuracy and product transferability between spatial scales. We investigate the potential of EO products for analysing terrestrial ecosystems. Results Land cover, productivity and fire products are generated from long-term data using standardized algorithms to improve reliability in detecting change of land surfaces. Their global coverage renders them useful for macroecology. Their spatial resolution (e.g. GLOBCOVER vegetation, 300 m; MODIS vegetation and fire, 500 m; ASTER digital elevation, 30 m) can be a limiting factor. Canopy structure and productivity products are based on physical approaches and thus are independent of biome-specific calibrations. Active fire locations are provided in near-real time, while burnt area products show actual area burnt by fire. EO products can be assimilated into ecosystem models, and their validation information can be employed to calculate uncertainties during subsequent modelling. Main conclusions Owing to their global coverage and long-term continuity, EO end products can significantly advance the field of macroecology. EO products allow analyses of spatial biodiversity, seasonal dynamics of biomass and productivity, and consequences of disturbances on regional to global scales. Remaining drawbacks include inter-operability between products from different sensors and accuracy issues due to differences between assumptions and models underlying the generation of different EO products. Our review explains the nature of EO products and how they relate to particular ecological variables across scales to encourage their wider use in ecological applications.
---
paper_title: Annual carbon balance of Canada's forests during 1895–1996

paper_content:

This paper reports annual carbon (C) balance of Canada's forests during 1895-1996 estimated using the Integrated Terrestrial Ecosystem C-budget model (InTEC) [Chen et. al., this issue]. During 1895-1910, Canada's forests were small sources of 30±15 Tg C yr -1 due to large disturbances (forest fire, insect-induced mortality, and harvest) in late nineteenth century. The forests became large sinks of 170±85 Tg C yr -1 during 1930-1970, owing to forest regrowth in previously disturbed areas and growth stimulation by nondisturbance factors such as climate, atmospheric CO 2 concentration, and N deposition. In recent decades (1980-1996), Canada's forests have been moderate sinks of 50±25 Tg C yr -1 , as a result of a tradeoff between the negative effects of increased disturbances and positive effects of nondisturbance factors. The nondisturbance factors, in order of importance, are (1) atmospheric N deposition (measured by a national monitoring network), (2) net N mineralization and fixation (estimated from temperature and precipitation records), (3) growing season length increase (estimated from spring air temperature records), and (4) CO 2 fertilization (estimated from CO 2 records using a leaf-level photosynthesis model). The magnitudes of modeled nondisturbance effects are consistent with simulation results by the Carnegie-Ames-Stanford Approach (CASA) and are also in broad agreement with flux measurements above mature forest stands at several locations in Canada. Results for the disturbance effects agree with a previous study [Kurz and Apps, 1996]. The overall C balance from InTEC generally agrees with that derived from tree ring data [Auclair and Bedford, 1997] and from forest inventories. The combination of our result and that of Houghton et al. [1999] for the United States suggests that North America (> 15°N), was probably a C sink of 0.2-0.5 Pg C yr -1 during 1980s, much less than that of 1.7 Pg C yr -1 estimated by Fan et al. [1998] using an atmospheric inversion method.
---
paper_title: Three distinct global estimates of historical land-cover change and land-use conversions for over 200 years

paper_content:

Earth’s land cover has been extensively transformed over time due to both human activities and natural causes. Previous global studies have focused on developing spatial and temporal patterns of dominant human land-use activities (e.g., cropland, pastureland, urban land, wood harvest). Process-based modeling studies adopt different strategies to estimate the changes in land cover by using these land-use data sets in combination with a potential vegetation map, and subsequently use this information for impact assessments. However, due to unaccounted changes in land cover (resulting from both indirect anthropogenic and natural causes), heterogeneity in land-use/cover (LUC) conversions among grid cells, even for the same land use activity, and uncertainty associated with potential vegetation mapping and historical estimates of human land use result in land cover estimates that are substantially different compared to results acquired from remote sensing observations. Here, we present a method to implicitly account for the differences arising from these uncertainties in order to provide historical estimates of land cover that are consistent with satellite estimates for recent years. Due to uncertainty in historical agricultural land use, we use three widely accepted global estimates of cropland and pastureland in combination with common wood harvest and urban land data sets to generate three distinct estimates of historical land-cover change and underlying LUC conversions. Hence, these distinct historical reconstructions offer a wide range of plausible regional estimates of uncertainty and the extent to which different ecosystems have undergone changes. The annual land cover maps and LUC conversion maps are reported at 0.5°×0.5° resolution and describe the area of 28 landcover types and respective underlying land-use transitions. The reconstructed data sets are relevant for studies addressing the impact of land-cover change on biogeophysics, biogeochemistry, water cycle, and global climate.
---
paper_title: Landscape – wildfire interactions in southern Europe: Implications for landscape management

paper_content:

Every year approximately half a million hectares of land are burned by wildfires in southern Europe, causing large ecological and socio-economic impacts. Climate and land use changes in the last decades have increased fire risk and danger. In this paper we review the available scientific knowledge on the relationships between landscape and wildfires in the Mediterranean region, with a focus on its application for defining landscape management guidelines and policies that could be adopted in order to promote landscapes with lower fire hazard. The main findings are that (1) socio-economic drivers have favoured land cover changes contributing to increasing fire hazard in the last decades, (2) large wildfires are becoming more frequent, (3) increased fire frequency is promoting homogeneous landscapes covered by fire-prone shrublands; (4) landscape planning to reduce fuel loads may be successful only if fire weather conditions are not extreme. The challenges to address these problems and the policy and landscape management responses that should be adopted are discussed, along with major knowledge gaps.
---
paper_title: Determinants and predictability of global wildfire emissions

paper_content:

Abstract. Biomass burning is one of the largest sources of atmospheric trace gases and aerosols globally. These emissions have a major impact on the radiative balance of the atmosphere and on air quality, and are thus of significant scientific and societal interest. Several datasets have been developed that quantify those emissions on a global grid and offered to the atmospheric modelling community. However, no study has yet attempted to systematically quantify the dependence of the inferred pyrogenic emissions on underlying assumptions and input data. Such a sensitivity study is needed for understanding how well we can currently model those emissions and what the factors are that contribute to uncertainties in those emission estimates. Here, we combine various satellite-derived burned area products, a terrestrial ecosystem model to simulate fuel loads and the effect of fire on ecosystem dynamics, a model of fuel combustion, and various emission models that relate combusted biomass to the emission of various trace gases and aerosols. We carry out simulations with varying parameters for combustion completeness and fuel decomposition rates within published estimates, four different emissions models and three different global burned-area products. We find that variations in combustion completeness and simulated fuel loads have the largest impact on simulated global emissions for most species, except for some with highly uncertain emission factors. Variation in burned-area estimates also contribute considerably to emission uncertainties. We conclude that global models urgently need more field-based data for better parameterisation of combustion completeness and validation of simulated fuel loads, and that further validation and improvement of burned area information is necessary for accurately modelling global wildfire emissions. The results are important for chemical transport modelling studies, and for simulations of biomass burning impacts on the atmosphere under future climate change scenarios.
---
paper_title: The influence of vegetation, fire spread and fire behaviour on biomass burning and trace gas emissions: results from a process-based model

paper_content:

A process-based fire regime model (SPITFIRE) has been developed, coupled with ecosystem dynamics in the LPJ Dynamic Global Vegetation Model, and used to explore fire regimes and the current impact of fire on the terrestrial carbon cycle and associated emissions of trace atmospheric constituents. The model estimates an average release of 2.24 Pg C yr−1 as CO2 from biomass burning during the 1980s and 1990s. Comparison with observed active fire counts shows that the model reproduces where fire occurs and can mimic broad geographic patterns in the peak fire season, although the predicted peak is 1–2 months late in some regions. Modelled fire season length is generally overestimated by about one month, but shows a realistic pattern of differences among biomes. Comparisons with remotely sensed burnt-area products indicate that the model reproduces broad geographic patterns of annual fractional burnt area over most regions, including the boreal forest, although interannual variability in the boreal zone is underestimated.
---

Title: Ten years of global burned area products from spaceborne remote sensing - A review: Analysis of user needs and recommendations for future developments

Section 1: Introduction
Description 1: Provide historical context and the importance of fire disturbance as an essential climate variable (ECV). Outline the goals of current research on global burned area (BA) remote sensing products and the need for improved fire observations.

Section 2: GFED (Global Fire Emissions Database)
Description 2: Describe the details, methodology, and improvements of the GFED3 product, including its period of coverage and inter-annual variability.

Section 3: MCD45A1
Description 3: Present the standard MODIS BA product, its algorithms, spatial resolution, and coverage period.

Section 4: L3JRC
Description 4: Discuss the L3JRC global burned area data, its generation process, and the institutions involved.

Section 5: Globcarbon
Description 5: Elaborate on the Globcarbon BA product, its development, spatial resolution, and the period it covers.

Section 6: GBS
Description 6: Explain the Global Burned Surfaces product, its derivation from NOAA-AVHRR images, and its limitations.

Section 7: GLOBSCAR and GBA2000
Description 7: Give an overview of these two benchmark projects, their development, and their contributions to subsequent projects.

Section 8: General overview on the increasing use of BA products reported in the literature since 2000
Description 8: Analyze the use of global BA products in peer-reviewed studies and their distribution across different research fields and regions.

Section 9: A literature review on BA product applications
Description 9: Summarize the main uses of BA products and their requirements in terms of temporal, spatial, and thematic characteristics.

Section 10: Fire hazard assessment for ecosystem management
Description 10: Discuss the need for accurate fire statistics for fire risk assessment systems and the impacts of fire on ecosystems and society.

Section 11: Early warning fire alert systems and survey
Description 11: Examine the public interest in near real-time fire alert systems and the requirements for improving BA products to avoid major negative impacts.

Section 12: Atmospheric chemistry
Description 12: Outline the significance of biomass burning as a major emission source for trace gases and aerosols and the incorporation of BA products in atmospheric chemistry models.

Section 13: Biogeochemical models
Description 13: Discuss biogeochemical models used for estimating biomass and carbon emissions, and the role of BA products in these models.

Section 14: Dynamic Global Vegetation Models (DGVMs)
Description 14: Detail the use of DGVMs for simulating vegetation distribution, fire emissions, and the requirements for global BA products in these models.

Section 15: Current weaknesses and failures: a review of evaluation and inter-comparison of BA products
Description 15: Review the limitations of existing BA products, their accuracy, and discrepancies identified in intercomparison exercises.

Section 16: Forthcoming targets for BA products: a review of requirements identified by previous international science programmes
Description 16: Summarize the target requirements for fire observation set by international science programmes and the core characteristics for future BA products.

Section 17: Questionnaire format
Description 17: Describe the design of the questionnaire used to identify user requirements for BA products.

Section 18: End-user description
Description 18: Provide an overview of the end-users who responded to the questionnaire, their geographic distribution, and their fields of research.

Section 19: Accuracy requirements
Description 19: Discuss the accuracy requirements for future BA products as derived from the questionnaire responses.

Section 20: Geolocation
Description 20: Explain the importance of geolocation accuracy for different user communities and their specific requirements.

Section 21: Timing
Description 21: Present the users' requirements for the timing of fire events and the acceptable errors in temporal resolution.

Section 22: Quality indicators
Description 22: Summarize the desired quality indicators and metadata information for different BA product types based on user feedback.

Section 23: Data format and product dissemination
Description 23: Discuss the preferred data formats, metadata specifications, and data access methods for end-users.

Section 24: Conclusion on recommendations for BA development and use
Description 24: Provide final recommendations for the development of new global burned area data, focusing on user needs and technical limitations.

Section 25: Appendix A. Supplementary data
Description 25: Include information on supplementary data associated with the paper, available online.