简介：Basedonthedataupto1999fromhydroclimatologicaldepartments,thispaperanalyzestheclimaticdivideimplicationsoftheQinlingMountainsinregionalresponsetotheprocessofclimatewarming,duetowhichthegradesofdryness/wetness(GDW)in100yearsshowthatthenorthernregionhasenteredadroughtperiod,whilethesouthernisahumidperiod.Inacourseoftenyears,theD-valueofannualaverageairtemperatureoversouthernShaanxi(theHanjiangValley)andtheCentralShaanxiPlain(theGuanzhongPlain)hasnarrowed,i.e.,theformerwithaslightchangeandthelatterwithrapidincreaseintemperature.BothregionswerearidwiththedecreaseinprecipitationD-value,namelytheplainbecamewarmerwhilethesouthwasdrier.TheQinlingMountainsplayapronouncedroleintheclimaticdivide.Therunoffcoefficient(RC)oftheWeiheRiverdecreasessynchronouslywiththatoftheHanjiangduetoclimatewarming.TheRCofWeihedroppedfrom0.2inthe1950stolessthan0.1inthe1990s.TheWeiheValley(theGuanzhongPlain)ispracticallyanaridareaduetoshortageofwater.Thesuccessive0.5,1.0℃temperatureanomalyoverChinamarks,perhaps,theimportanttransitionperiodinwhichtheenvironmentbecomesmorevulnerablethanbefore.Thestudyshowstheobvioustrendofenvironmentalaridity,whichisofhelptotheunderstandingofregionalresponsetoglobalclimatechange.