Thursday, 16 August 2007

Climate Change Part 12 (Arctic Sea Ice - Now You See It)

I've got some shocking news! After studying the BBC's data on Arctic ice during the period 1990-1996 it seems that it expanded by a massive 21.52% (that is 1.7 million square km or seven times the size of the UK). But before you go out and buy that winter clothing or order triple glazing, you will be glad to know that Arctic ice is now back to the 1990 level. Phew! I bet you thought we were in for another Ice Age.

The Article published on the BBC news website is every bit as misleading as the first sentence of the above paragraph. The article tells us that Arctic ice is at a record low and that we could see the Arctic ice-free by 2040. Monkeys may also fly out of my arse!

In the Paper: Arctic decadal and interdecadal variability by Igor V. Polyakov (International Arctic Research Center, University of Alaska Fairbanks) and Mark A. Johnson (Institute of Marine Science, University of Alaska Fairbanks) they come to the following conclusions:

The recent retreat of arctic ice requires an understanding of whether the ice reduction is a persistent signature of global warming due to anthropogenic impact on climate or it is a minimum of a low-frequency natural climate oscillation. Numerical models of Earth climate system [Vinnikov et al., 1999] and direct observations [Rothrock et al., 1999] show substantial ice decline in the recent decades. Vinnikov et al. suggested that the observed decrease of arctic ice extent is related to anthropogenic global warming. However, Vinje [2000] using observations over the past 135 years showed that the recent decrease in ice extent in the Nordic Seas is within the range of natural variability since the 18th century. A combination of century- and half-a-century-long data records and model integrations leads us to conclude that the natural low-frequency oscillation (LFO) exists and is an important contributor to the recent anomalous environmental conditions in the Arctic. This mode of oscillation is related to fluctuations in the thermohaline circulation in the North Atlantic [Delworth and Mann, 2000]. Comparison of the century-long NAO index time series and half a century time series of the polar region SAT, SLP differences, and wind vorticity index shows the existence of the LFO mode in the latter time series. There is evidence that the LFO has a strong impact on ice and ocean variability. Our results suggest that the decadal AO and multidecadal LFO drive large amplitude natural variability in the Arctic making detection of possible long-term trends induced by greenhouse gas warming most difficult.

Don't believe the scare mongers.

1 comment:

Lucky7Star said...

1.Since July, the smallest record of sea ice area in the Arctic Ocean has been broken every day.
2.Since the beginning of August, the shrinkage of sea ice has been accelerated by a low pressure system generated and lingering off Siberia.
3.On August 15, the total sea ice area in the Arctic Ocean reached a new low.
4.If this pace of melting continues, the sea ice area reduction pace may significantly exceed the IPCC forecast, and it may actually reach the forecasted values for 2040 to 2050.