desert desert barren area land little precipitation occurs consequently living conditions hostile plant animal life lack vegetation unprotected surface ground processes land surface world arid semi arid includes polar regions little precipitation occurs called polar cold classified precipitation falls temperature causes geographical location formed processes large variations temperature day night strains rocks consequently break pieces rain seldom occurs occasional result flash floods rain falling hot rocks cause resulting fragments rubble desert floor eroded wind picks particles sand dust aloft sand dust storms wind blown sand grains striking solid object path surface rocks wind sorts sand uniform deposits grains end level sheets sand high sand dunes flat plains fine material blown away surface consists mosaic smooth stones areas known desert little erosion takes place desert features include rock exposed bedrock deposited flowing water temporary lakes form salt left waters underground sources water form springs found occur plants animals living desert need special adaptations survive harsh environment plants tend tough small leaves water resistant spines deter annual plants bloom die course weeks rainfall long lived plants survive years deep root systems able tap underground moisture animals need cool find food water survive nocturnal stay shade underground heat day tend efficient water needs food concentrating animals remain state long periods ready active rare rains fall reproduce rapidly conditions favorable returning people struggled live surrounding semi arid lands moved flocks grazing available provided opportunities settled way life cultivation semi arid regions encourages erosion soil causes increased desert farming possible aid irrigation california provides example previously barren land productive import water outside source trade routes forged especially traditionally carrying salt gold ivory goods large numbers slaves taken northwards mineral extraction takes place sunlight gives potential capture large quantities solar energy etymology english desert romance including italian portuguese french spanish come ecclesiastical latin originally abandoned place abandon sparse population complex dynamic varying culture era technologies use word desert cause confusion english 20th century desert sense area specific reference today word climate science sense area low precipitation phrases desert island great american desert previous centuries necessarily imply sand focus sparse population physical geography desert region land dry receives low amounts precipitation usually form rain snow mist fog little coverage plants streams dry supplied water outside area described areas water lost falls precipitation generally receive precipitation year regions receive clad grass known classification defined classified number ways generally combining total precipitation number days falls temperature humidity additional factors example phoenix arizona receives precipitation year immediately recognized located desert adapted plants alaska receives precipitation year classified cold desert regions world cold including areas high altitude areas parts world polar cover ice free areas arctic non technical definition parts earth surface insufficient vegetation cover support human population potential measurement precipitation providing scientific measurement based definition desert water budget area calculated formula precipitation potential rates surface storage water combination water loss atmospheric life processes plants potential water given region example arizona receives rain year water course year words times water region actually falls rain rates cold regions alaska lower lack heat aid process classified hot cold coastal characteristics hot include high temperatures summer greater precipitation usually exacerbated high temperatures strong winds lack cloud cover considerable variation occurrence precipitation intensity distribution low humidity winter temperatures vary considerably different related location desert continental latitude daily variations temperature great heat loss radiation night increased clear skies cold known temperate occur higher latitudes hot caused air cold far ocean separated mountain ranges sea cases insufficient moisture air cause precipitation largest found occur eastern rocky_mountains eastern southern southern australia polar particular class cold desert air cold carries little moisture little precipitation occurs fall usually snow carried strong wind form dunes similar caused dust sand desert regions antarctica example annual precipitation central plateau times major based precipitation receive rainfall year annual seasonal cycle precipitation experience month periods rainfall arid receive year factors temperature humidity rate moisture storage capacity ground marked effect degree plant animal life sustained rain falling cold season effective promoting plant growth defining boundaries regions surround grounds precipitation problematic coastal found western edges continental land masses regions cold currents approach land cold water rise ocean depths cool winds crossing water pick little moisture coastal regions low temperatures low rainfall main precipitation form fog range temperatures daily annual scale relatively low respectively type long narrow bounded east mountain ranges occur south west africa chile southern california baja california coastal influenced cold currents found western_australia western fringes divided desert regions earth categories according precipitation received widely accepted system extremely arid lands consecutive months precipitation arid lands annual precipitation lands mean annual precipitation extremely arid arid lands considered lands generally referred classified according geographical location dominant weather pattern trade wind mid latitude rain shadow coastal monsoon polar trade wind occur horse latitudes belts associated subtropical anticyclone large scale descent dry air moving high altitudes poles desert type mid latitude occur areas remote sea moisture precipitated prevailing winds include monsoon similar occur regions large temperature differences occur sea land moist warm air rises land deposits water content sea inland areas receive little precipitation near india pakistan border type parts world created rain shadow effect lift occurs air masses rise pass high ground process cool lose moisture precipitation slope mountain range descend warm capacity hold moisture increases area relatively little precipitation occurs example lying rain shadow receiving precipitation annually areas arid virtue long way nearest available sources moisture arid places high altitude prominent example found north locations category elevations exceeding thermal regime places owe profound average annual precipitation far nearest available sources moisture lee mountain ranges normally cold hot day cold night true northeastern slopes polar remain ice free dry winds flow downhill surrounding mountains desert areas presently non arid environments nebraska known climate classification system classed hot desert temperate desert climate classification system classified arid climates processes usually large seasonal temperature range high daytime temperatures falling sharply night range rock surface experiences greater temperature day sky usually clear sun radiation reaches ground soon sun sets desert quickly heat space hot temperature daytime exceed summer freezing point night winter large temperature variations destructive effect exposed rocky surfaces repeated fluctuations strain exposed rock flanks mountains crack fragmented strata slide valleys continue break pieces relentless sun day night successive strata exposed relief internal pressure built rocks underground cause occurs outer surfaces rocks split flat believed caused stresses rock repeated expansions parallel original surface chemical processes probably play important role previously thought necessary moisture present form mist ground water drawn surface formation salt crystals rock particles sand rocks shallow caves formed base cliffs means desert mountains decay large areas shattered rock rubble occur process continues end products dust sand dust formed solidified clay volcanic deposits sand results harder limestone sandstone certain critical size temperature induced rocks occur provides minimum size sand grains mountains eroded sand created high wind speeds sand grains picked surface blown process known airborne grains act sand blasting mechanism away solid objects path energy wind transferred ground sand eventually ends deposited level areas known sand fields sand seas dunes dust storms sand dust storms natural events occur arid regions land protected covering vegetation dust storms usually start desert margins finer materials blown away steady wind begins blow fine particles lying exposed ground begin greater wind speeds particles lifted air stream land strike particles air turn starting chain reaction ejected particles possible ways depending size shape density suspension suspension possible particles diameter dust storm fine particles lifted aloft heights reduce visibility remain atmosphere days end conveyed trade winds distances clouds dust formed stronger winds moving land leading edge sunlight dark night ground level study dust storm china estimated million tons dust involved covering area km2 mean particle size smaller scale short lived phenomenon occur calm conditions hot air near ground rises quickly small pocket cooler low pressure air forming column particles dust devil occur frequency dust storms preceded severe dust storms occur wind velocity increases point lift heavier particles grains sand diameter air soon fall earth particles process weight prevents airborne long travel distance meters yards sand streams surface ground like fluid rising heights severe steady blow high sand stream rise largest sand grains airborne transported rolled desert floor performing short jumps wind blown sand particles electrically charged electric fields range size produce sparks cause interference telecommunications equipment unpleasant humans cause electric fields caused collision airborne particles impacts sand grains landing ground mechanism little understood particles usually negative charge diameter positive major earth land surface salt covered flats processes major factors shaping desert landscapes polar seen cold similar features main form precipitation snow rain antarctica world largest cold desert composed thick continental ice sheet barren rock barren rock found called dry valleys antarctica snow ice lakes suggest far greater rare snowfall strong winds ice hot cold play earth temperature reflect incoming light higher forests sea features people think consisting extensive areas sand dunes way depicted films look like world desert sand varying north_america australia sand occur usually large quantities form sand sheets extensive areas dunes sand sheet near level firm partially consolidated particles layer varies centimeters meters thick structure sheet consists thin horizontal layers coarse fine medium grain sand separated layers coarse sand gravel single grain thick larger particles anchor particles place packed surface form miniature desert pavement small form sand sheet wind exceeds mph form perpendicular wind direction gradually surface wind continues blow distance corresponds average length jumps particles change wind direction causes sand dunes sand ridges form sources dry loose sand occur climatic conditions cause airborne particles settle wind blows place individual grains sand reach crest cascade far slope typically gradient lee slope angle loose dry sand slip wind induced movement sand grains takes place moves slowly surface ground dunes solitary grouped fields extensive known sand seas shape depends characteristics prevailing wind dunes produced strong winds blowing level surface crescent shaped concave away wind directions winds regularly blow series long linear dunes known dunes form occur parallel strong wind blows general direction transverse dunes run right angle prevailing wind direction star dunes formed variable winds ridges slip faces central point tend grow vertically reach height making tallest type rounded sand slip face rare dome dunes found edges sand seas large surface area world consists flat stone covered plains dominated wind erosion wind continually removes fine material wind blown sand material mainly larger stones leaving desert pavement area land closely packed smooth stones forming mosaic different theories exist exactly pavement formed sand dust blown away wind stones place alternatively stones previously ground way work surface little erosion takes place formation pavement ground stable brings moisture surface action calcium precipitated binding particles form desert time bacteria live surface stones accumulate film minerals clay particles forming shiny brown coating known desert non sandy consist exposed bedrock dry soils variety affected flowing water fans temporary permanent lakes type desert landscape consisting high rocky plateau sand removed processes include plains largely covered angular finer particles stripped wind called western eastern plains australia central asia algeria impressive eroded sandstone blocks places wind carved holes arches created mushroom like pillars narrower base water force cut way high desert floor creating canyon mile feet meters deep places exposing strata billion year old water places earth virtually devoid life blocked receiving precipitation mountains east west cold anticyclone pacific essential dry climate average precipitation chilean region year weather stations received rain evidence suggests significant rainfall arid mountains reach high completely free glaciers southern free extends altitude continuous plant life form specialist plants obtain moisture blow pacific rain falls occasionally great violence desert surface evidence dry stream channels known surface experience flash floods raging surprising storm kilometers away basins drainage sea crossed exotic rivers sourced mountain ranges high rainfall areas borders losing water pass desert raising levels nearby underground sources water form springs underground rivers lakes lie close surface wells dug form plant animal life flourish sandstone system largest known accumulation fossil water great man river scheme launched libya colonel tap supply water coastal cities egypt long largest oasis lake occupied depression ancient times thick deposits sandy clay resulted wells dug extract water sandstone lies underneath occur walls pools survive deep shade near dried lakes form basins sufficient precipitation glaciers usually shallow wind blowing surface cause stress moving water nearby low lying areas lakes dry leave crust area deposited clay sand known north_america relics covered parts utah nevada idaho ice age climate colder include great salt lake utah lake lake dry lake beds smooth flat surfaces attempted vehicle speed records black rock desert united_states_air_force uses aircraft space shuttle flora plants face severe challenges arid environments problems need solve include obtain water avoid eaten reproduce key plant growth place day energy sun required day hot opening allow carbon dioxide necessary process causes conservation water priority desert vegetation plants resolved problem adopting acid allowing open night allow enter close day carbon desert plants reduced size leaves abandoned altogether desert specialists species leaves displaced cellular structure modified allow store water rain falls water rapidly absorbed shallow roots retained allow survive months years away giant desert form forests providing shade plants nesting places desert birds grow slowly live years surface trunk folded like allowing expand large specimen hold tons water good restricted north_america plants developed similar strategies process known evolution limit water loss reducing size number having tiny leaves deciduous leaves season leaves reduce store water leaves stems desert plants maximize water having shallow roots spread widely developing long reach deep rock strata ground water australia leaves salt crystals enabling live areas common developed spines ward animals desert plants produce seed lies dormant soil sparked growth rainfall plants grow great flower set seed weeks aiming complete development water perennial plants reproduction likely successful seed shaded position close parent plant competition seed blown desert floor seed coat seed tree grows americas hard fails planted carefully passed gut readily little pile moist provides excellent start life away parent tree stems leaves plants lower surface velocity sand carrying winds protect ground erosion small fungi microscopic plant organisms found soil surface called soil vital link preventing erosion providing support living organisms plants including reproduce wind living environment cold high concentrations salt soil grasses low shrubs dominant vegetation ground covered shrubs leaves shed year fauna animals adapted live called evidence body temperature mammals birds different climates great heat cold fact exceptions basal rate determined body size climate live desert animals plants especially clear evolutionary adaptations water conservation heat tolerance studied comparative physiology evolutionary physiology studied example shown desert inhabiting species examples evolution identified desert organisms including rats present challenging environment animals require food water need body temperature level ways birds able higher animals areas greater food availability desert local rainfall fly hot birds remove heated desert floor cooler air great heights order conserve energy desert birds run fly cream colored ground long legs stopping periodically insects like desert birds coloring merge landscape stationary expert nests open desert floor dozens kilometers miles away needs visit daily small birds found restricted plumage matches color underlying surface desert takes frequent dust ensures matches environment water carbon dioxide end products proteins produces grams water protein produces grams water fat produces grams water making possible live little access drinking water rat example makes use water water having low basal rate remaining underground heat day reducing loss water skin respiratory system rest mammals obtain moisture plants eat species grant efficient apparently need drink superb example adapted desert life water loss producing concentrated dry able lose body weight water loss dying obtain water needs body prey hot desert animals nocturnal seeking shade day dwelling underground depths remain regardless external temperature desert rats rats small emerge night snakes prey cool increasing rate skin mammals living cold developed greater warmer body fur layers fat beneath skin arctic rate times high expected animal size birds avoided problem losing heat feet attempting maintain temperature rest bodies form emperor dense plumage layer air layer skin strategies maintain body temperature environments earth reptiles unable live cold suited hot ones heat day temperature rise reptiles survive temperature heat adaptations desert life unable cool shelter heat day night ground heat absorbed day emerge search prey snakes numerous arid regions certain snakes developed novel method enables navigate high sand dunes include africa north_america distinct similar patterns evolution desert reptiles ambush predators bury sand waiting prey come range amphibians unlikely desert need skins moist dependence water reproductive purposes fact species found habitat remarkable adaptations spending hot dry months deep shed skins number times retain remnants retain moisture desert couch spends year dormant heavy rain trigger emergence male find suitable pool calls attract eggs laid grow rapidly reach water desert adult juveniles stay surface feeding growing soon dig adulthood water holding frog australia similar life cycle long years rain falls desert rain frog nocturnal survives damp sea roll atlantic invertebrates particularly successfully homes desert flies beetles ants spiders hard water lay eggs underground young develop away temperature extremes surface silver uses heat shock protein novel way open brief heat day long legged beetle stands legs raises catch morning mist water mouth use pools form rain complete life cycle matter days desert shrimp appearing new formed dormant eggs hatch fairy lose soon rains temporary pools human relations humans long use places live recently started exploit minerals energy capture play significant role human culture extensive literature history people living australia tribes north american indians originally hunter developed skills manufacture use weapons animal tracking finding water foraging edible plants things found natural environment supply everyday needs self sufficient skills knowledge passed generations word mouth cultures developed nomadic way life sheep goats cattle travelled large areas moving new seasonal erratic rainfall encouraged new plant growth took tents cloth skins poles diet included milk blood meat desert traders large land stretching atlantic rim egypt trade routes developed linking south fertile mediterranean region north large numbers carry valuable goods desert interior traders goods transported traditionally included slaves ivory gold going northwards salt going southwards knowledge region employed guide wells million slaves taken northwards 8th 18th centuries traditional means overland transport declined advent motor vehicles shipping air freight travel routes carrying salt interior desert edge communities round precipitation occurred conditions suitable groups took crops happened drought caused death herd animals forcing turn cultivation mercy weather lived bare level land cultivated reduced area available nomadic causing disputes land semi arid fringes desert fragile soils risk erosion exposed happened american dust bowl 1930s grasses held soil place series dry years caused crop failures enormous dust storms blew away half million americans forced leave land similar damage today semi arid areas rim million hectares land turned desert year caused factors drought climatic shifts agriculture vegetation plays major role determining composition soil environments rate erosion run increases dramatically reduced vegetation cover unprotected dry surfaces tend blown away wind washed away flash floods leaving soil layers sun historically considered cause evidence wild animals actually improve fertility vegetation cover removal encourages processes natural resource extraction contain substantial mineral resources entire surface giving characteristic colors example red sand comes minerals geological processes desert climate concentrate minerals valuable deposits ground water extract ore minerals according water table concentrated form similarly tends concentrate minerals desert lakes creating dry lake beds rich minerals concentrate minerals variety deposits including found usa great basin desert historically exploited teams pulling nearest railway desert especially rich mineral chile mined explosives desert minerals copper chile peru iran iron australia metals commercially valuable types rock extracted world oil gas form shallow seas micro organisms conditions later covered sediment time sites shallow seas underlying deposits transported movement plates major found sands saudi_arabia believe oil deposits formed processes ancient case major american oil fields farming traditional desert farming systems long established north_africa irrigation key success area water stress limiting factor growth techniques include irrigation use organic animal traditional agricultural management fertility built crop production preserves soil destruction wind forms erosion found plant growth promoting bacteria play role increasing resistance plants stress conditions soil vicinity plants study found desert farming establishing islands fertility allowing farmers achieve increased yields despite adverse environmental conditions field trial desert exposed roots different species tree nitrogen fixing aim restoring degraded lands partially successful farmed 7th century iron age supply food desert forts native americans south western united_states seeds technologies available mexico techniques grew gardens moist areas foot dunes near streams providing flood irrigation areas extensive specially built canals tribe constructed miles large canals maintained centuries impressive feat engineering grew beans modern example desert farming california high temperatures average rainfall year economy heavily based agriculture land network canals sourced entirely soil deep fertile river flood plains desert transformed productive farming regions california water river urban communities expense river extraction sites longer ground flow year problem growing crops way build soil caused river water desert remains time viewed future means increasing food production world growing population prospect proved false disregarded environmental damage caused diversion water desert project irrigation solar energy capture increasingly seen sources solar energy partly low amounts cloud cover successful solar power plants built plants combined capacity making largest solar power installation world large desert covered mirrors including fields solar collectors currently construction produce completed potential generating solar energy huge highest found globe professor stated technology exists supply world electricity needs industrial initiative consortium seeking billion invest north african solar wind installations years supply electricity europe cable lines running mediterranean_sea european interest stems aspects continual daytime sunshine plenty unused land receives sunshine acre europe space totalling hundreds square miles required house fields mirrors solar plants israel surrounding area including receive plenty sunshine generally resulted construction solar plants proposed giant solar plants supply israel needs electricity warfare arabs probably organized force conduct successful battles desert knowing routes locations utilizing muslim arab forces able successfully overcome roman persian forces period expansion islamic centuries later world wars saw fighting desert world war ottoman turks engaged british regular army campaign spanned arabian peninsula turks defeated british backing irregular arab forces seeking revolt turks famous book seven second world war began italian libya warfare desert offered great scope use large open spaces casualties civilian populations tanks armoured vehicles able travel large distances land mines laid large numbers size terrain meant supplies needed brought great distances battle advance supply chain necessarily longer defeated army retreat resupply reasons line moved forth hundreds kilometers lost regained momentum easterly point egypt allies decisively defeated axis forces culture desert generally thought barren landscape portrayed writers film makers philosophers artists critics place extremes metaphor death war religion primitive past future extensive literature subject early historical account travelled china crossing number year trek accounts vivid descriptions desert conditions accounts journeys interwoven reflection case major work travels described flying desert wind sand stars bell travelled extensively arabian desert early 20th century expert subject writing books advising british government dealing arabs woman explorer travelled middle_east visiting turkey syria persia afghanistan writing books experiences german naturalist spent years living recording experiences research book earth american poet expressed bleak thoughts poem ends stanza scare spaces stars stars human race nearer home scare desert places planets mars planet solar system identified despite low surface atmospheric pressure earth patterns atmospheric circulation mars formed sea sand million million area larger earth principally consist dunes form half flat areas near permanent polar ice caps north planet smaller fields occupy situated polar regions examination surface rocks laser shown surface film resembles desert found earth surface dust surface moon saturn desert like surface seas
Desert