ISMH-国际水文研究方法学术研讨会10.30-11.1(论文集)

Oct.30,2005CollegeofWaterSciences,BNU1DetectionofDecadalTrendforthePrecipitationintheTibetanPlateauZongxueXUCollegeofWaterSciencesBeijingNormalUniversityOct.30,2005CollegeofWaterSciences,BNU2ContentsIntroductionTechniquedescriptionStudyareadescriptionDatadescriptionResultanalysisConclusionsOct.30,2005CollegeofWaterSciences,BNU3IntroductionFactandchallengesTemperatureincreasesStreamflowcessationsBackgroundandreasonsAnthropogenic?Climatechange?Short-termclimaticcycle?Long-termseculardecline/rising?Oct.30,2005CollegeofWaterSciences,BNU4Temperature/PrecipitationQinghai(Zhaietal.,1999):TemperatureincreasedPrecipitationdecreasedXinjiang(Xuetal.,2004)TemperatureincreasedPrecipitationincreasedTibetanregion?Oct.30,2005CollegeofWaterSciences,BNU5NullHypothesisH0:=0TestStatistics:RejectH0:0,)var(10,00,)var(1SSSSSSSZc21ZZcNonparametricKendallTestOct.30,2005CollegeofWaterSciences,BNU6KendallSlopeIncreasetrend:β0Decreasetrend:β0ijjixxMedianji,Oct.30,2005CollegeofWaterSciences,BNU7StudyAreaGertsePalgonAmdoPurangShantsaShigatseNyemoLhasaZedangTingriTsonaLhuntseSokshanChaliPomeNyingtriZayulShiquanheTengchenChamdoZogongNakchuNyalamLhatseGyantseDamshungPaliOct.30,2005CollegeofWaterSciences,BNU8StudyAreaDescriptionPhysiographicregionsHimalayaregionSouthernTibetanvalleyNorthernTibetanvalleyEasternTibetanregionClimaticzoningNorthernTibetanregion:0oCSouthwesternTibetanregion:(0oC,5oC)YarlungTsangpoRiverbasin:5oCOct.30,2005CollegeofWaterSciences,BNU9CharacteristicsofPrecipitationStatisticsPrecipitation(mm)Average444.2Standarddeviation46.0Coefficientofvariation0.10Coefficientofskewness-0.14Maximumvalue534.0Minimumvalue359.5Range174.5Oct.30,2005CollegeofWaterSciences,BNU10AirTemperature狮泉河改则班戈安多普兰申扎当雄拉孜拉萨聂拉尔定日错那隆子帕里索县丁青昌都嘉黎波密林芝左贡察隅狮泉河改则班戈安多那曲普兰申扎当雄拉孜日喀则尼木拉萨泽当聂拉尔定日江孜错那隆子帕里索县丁青昌都嘉黎波密林芝左贡察隅Oct.30,2005CollegeofWaterSciences,BNU11AnnulTemperature0.01.02.03.04.05.06.01970197519801985199019952000YearTemperature(℃)Oct.30,2005CollegeofWaterSciences,BNU12PrecipitationDistribution狮泉河改则班戈安多那曲普兰申扎当雄拉孜日喀则尼木拉萨泽当聂拉尔定日江孜错那隆子帕里索县丁青昌都嘉黎波密林芝左贡察隅Oct.30,2005CollegeofWaterSciences,BNU13AnnualPrecipitation100200300400500600196119661971197619811986199119962001YearPrecipitation(m)Oct.30,2005CollegeofWaterSciences,BNU14TemporalCharacteristicsFourperiods:1962–19701970–19801980–19851991-1998Wetterperiods1985–19911998–2001Oct.30,2005CollegeofWaterSciences,BNU15β=6.14mm/decadeLong-termTrend:SpatialDistributionofAnnualPrecipitationGertseAmdoPurangLhasaTsonaPomeNyingtriShiquanheNyalamPaliLhatseNakchuChamdoOct.30,2005CollegeofWaterSciences,BNU16β=0.52mm/decadeLong-termTrend:SpatialDistributionofAnnualPrecipitation:January狮泉河改则班戈安多普兰申扎当雄拉孜拉萨聂拉尔定日错那隆子帕里索县丁青昌都嘉黎波密林芝左贡察隅Oct.30,2005CollegeofWaterSciences,BNU17β=2.14mm/decadeLong-termTrends:SpatialDistributionofAnnualPrecipitation:April狮泉河改则班戈安多普兰申扎当雄拉孜拉萨聂拉尔定日错那隆子帕里索县丁青昌都嘉黎波密林芝左贡察隅Oct.30,2005CollegeofWaterSciences,BNU18β=-2.03mm/decadeLong-termTrend:SpatialDistributionofAnnualPrecipitation:July狮泉河改则班戈安多普兰申扎当雄拉孜拉萨聂拉尔定日错那隆子帕里索县丁青昌都嘉黎波密林芝左贡察隅Oct.30,2005CollegeofWaterSciences,BNU19Long-termTrend:SpatialDistributionofAnnualPrecipitation:Octoberβ=1.32mm/decade狮泉河改则班戈安多普兰申扎当雄拉孜拉萨聂拉尔定日错那隆子帕里索县丁青昌都嘉黎波密林芝左贡察隅Oct.30,2005CollegeofWaterSciences,BNU20-4.0-3.0-2.0-1.00.01.02.03.04.0Jan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.MonthSlope(mm/decade)Long-termTrend:TemporalDistributionofMonthlyPrecipitationOct.30,2005CollegeofWaterSciences,BNU21•Spatialdistribution•Lhatse,Pome:Sig.increasingcenters•Purang:Lowdecreasingcenter•Temporaldistribution•Autumn&Winter:Weakincreasing•Spring:Significantincreasing•Summer:Significantdecreasing•March:Strongestincreasing•June:StrongestdecreasingLong-termTrend:AnnualPrecipitationOct.30,2005CollegeofWaterSciences,BNU22ClimateChange?AnthropogenicImpacts?•Temperatureincreased•PrecipitationincreasedOct.30,2005CollegeofWaterSciences,BNU23ConclusionsSpatialdistribution27stations24increasingTwoincreasingcentersTemporaldistributionAutumn&Winter:WeakincreaseSpring:SignificantincreasingSummer:SignificantdecreasingChallengeAnthropogenicimpact?Climatechange?Oct.30,2005CollegeofWaterSciences,BNU24