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1.
Based on the meteorological data of 20 stations in the Hengduan Mountains region during 1961-2009, the annual and seasonal variation of potential evapotranspiration was analyzed in combination with the Penman-Monteith model. With the method of Spline interpolation under ArcGIS, the spatial distribution of potential evapotranspiration was presented to research the regional difference, and the correlation analysis was used to discuss the dominant factor affecting the potential evapotranspiration. The results indicated that the an-nual potential evapotranspiration showed a decreasing tendency since the 1960s, especially from the 1980s to 1990s, while it showed an increasing tendency since 2000. Regional potential evapotranspiration showed a rate of -0.17 mm a?1. Potential evapotranspiration in north, middle and south of the Hengduan Mountains exhibited decreasing trends over the studied period, and its regional trend was on the decline from southwest to northeast.  相似文献   

2.
1971-2010年若尔盖湿地潜在蒸散量及地表湿润度的变化趋势   总被引:1,自引:1,他引:0  
利用若尔盖、红原、玛曲3个气象站1971-2010年的地面气象观测资料,根据Penman-Monteith模型计算了若尔盖湿地的潜在蒸散量,发现若尔盖湿地年潜在蒸散量呈明显上升的趋势,上升趋势为9.1 mm/10a;若尔盖湿地潜在蒸散量在2001年出现了增大突变,2001-2010年平均潜在蒸散量比1971-2000年上升了28.6 mm;各季节潜在蒸散量均呈上升趋势,其中以秋季上升最明显,上升趋势为4.3 mm/10a。导致若尔盖湿地潜在蒸散量上升的主要气象因子是温度上升、相对湿度下降和降水量的减少,虽然日照时数减少和风速减小有利于潜在蒸散量的下降,但由于气温上升的趋势更明显,影响更大,所以若尔盖湿地潜在蒸散量呈明显的上升趋势。近40 a若尔盖湿地地表湿润度以-0.03/10a的趋势减小,其中2001-2010年比1981-1990年下降了0.11,下降十分明显;与此同时,年平均气温以0.41℃/10a的趋势上升,降水量以-13.5 mm/10a的趋势减少,虽然若尔盖湿地仍属于湿润区,但出现了明显的暖干化趋势。  相似文献   

3.
The Yarlung Zangbo River (YR) is the highest great river in the world, and its basin is one of the centers of human economic activity in Tibet. Using 10 meteorological stations over the YR basin in 1961–2005, the spatial and temporal characteristics of temperature and precipitation as well as potential evapotranspiration are analyzed. The results are as follows. (1) The annual and four seasonal mean air temperature shows statistically significant increasing trend, the tendency is more significant in winter and fall. The warming in Lhasa river basin is most significant. (2) The precipitation is decreasing from the 1960s to the 1980s and increasing since the 1980s. From 1961 to 2005, the annual and four seasonal mean precipitation is increasing but not statistically significant, especially in fall and spring. The increasing precipitation rates are more pronounced in Niyangqu and Palong Zangbo river basins, the closer to the upper YR is, the less precipitation increasing rate would be. (3) The annual and four seasonal mean potential evapotranspiration has decreased, especially after the 1980s, and most of it happens in winter and spring. The decreasing trend is most significant in the middle YR and Nianchu river basin. (4) Compared with the Mt. Qomolangma region, Tibetan Plateau, China and global average, the magnitudes of warming trend over the YR basin since the 1970s exceed those areas in the same period, and compared with the Tibetan Plateau, the magnitudes of precipitation increasing and potential evapotranspiration decreasing are larger, suggesting that the YR basin is one of the most sensitive areas to global warming.  相似文献   

4.
The Yarlung Zangbo River (YR) is the highest great river in the world, and its basin is one of the centers of human economic activity in Tibet. Using 10 meteorological stations over the YR basin in 1961–2005, the spatial and temporal characteristics of temperature and precipitation as well as potential evapotranspiration are analyzed. The results are as follows. (1) The annual and four seasonal mean air temperature shows statistically significant in-creasing trend, the tendency is more significant in winter and fall. The warming in Lhasa river basin is most significant. (2) The precipitation is decreasing from the 1960s to the 1980s and increasing since the 1980s. From 1961 to 2005, the annual and four seasonal mean precipi-tation is increasing but not statistically significant, especially in fall and spring. The increasing precipitation rates are more pronounced in Niyangqu and Palong Zangbo river basins, the closer to the upper YR is, the less precipitation increasing rate would be. (3) The annual and four seasonal mean potential evapotranspiration has decreased, especially after the 1980s, and most of it happens in winter and spring. The decreasing trend is most significant in the middle YR and Nianchu river basin. (4) Compared with the Mt. Qomolangma region, Tibetan Plateau, China and global average, the magnitudes of warming trend over the YR basin since the 1970s exceed those areas in the same period, and compared with the Tibetan Plateau, the magnitudes of precipitation increasing and potential evapotranspiration decreasing are larger, suggesting that the YR basin is one of the most sensitive areas to global warming.  相似文献   

5.
1960-2009年横断山区潜在蒸发量时空变化   总被引:8,自引:2,他引:6  
以横断山区20 个气象站1960-2009 年逐日气象数据为基础,应用1998 年FAO 修正的Penman-Monteith 模型分析了横断山区潜在蒸发量的变化,在ArcGIS 环境下通过样条插值法分析了潜在蒸发量变化的时空分异,并对影响潜在蒸发量变化的气象因素进行了讨论,结果表明:年潜在蒸发量自20 世纪60 年代中期以来呈波动减小趋势,20 世纪80 年代中期之后减小趋势更加明显,2000-2009 年呈增加趋势。潜在蒸发量的年际变化倾向率为-0.17 mm a-1,从空间分布来看,北部、中部、南部都呈减少趋势,倾向率由北向南逐渐减小。从季节来看,秋季和冬季潜在蒸发量呈增加趋势,春季和夏季呈减小趋势,春季减小趋势大于夏季,秋季增加趋势大于冬季。气温上升、风速和日照时数的降低是横断山区潜在蒸发量减少的主导因素,风速和日照时数的下降导致春季和夏季潜在蒸发量减小,气温上升导致秋季和冬季潜在蒸发量增加。  相似文献   

6.
横断山区土壤相对湿度时空分异   总被引:1,自引:0,他引:1  
以1992~2010年横断山区16个观测站土壤相对湿度资料为基础,通过Kriging插值法分析土壤相对湿度季节分异和空间分异特征。结果表明:横断山区年土壤相对湿度自1992年以来整体呈波动增加趋势,年际变化倾向率为0.51%/a;横断山区土壤相对湿度表现为西南和东北部较高,东南和西北部较低,中部土壤相对湿度增加趋势强于边缘,深层土壤的相对湿度整体大于浅层土壤。春、夏季土壤相对湿度增加趋势比秋、冬季明显。  相似文献   

7.
1971-2000年青藏高原气候变化趋势   总被引:2,自引:2,他引:0  
Trends of annual and monthly temperature, precipitation, potential evapotranspi- ration and aridity index were analyzed to understand climate change during the period 1971–2000 over the Tibetan Plateau which is one of the most special regions sensitive to global climate change. FAO56–Penmen–Monteith model was modified to calculate potential evapotranspiration which integrated many climatic elements including maximum and mini- mum temperatures, solar radiation, relative humidity and wind speed. Results indicate gen- erally warming trends of the annual averaged and monthly temperatures, increasing trends of precipitation except in April and September, decreasing trends of annual and monthly poten- tial evapotranspiration, and increasing aridity index except in September. It is not the isolated climatic elements that are important to moisture conditions, but their integrated and simulta- neous effect. Moreover, potential evapotranspiration often changes the effect of precipitation on moisture conditions. The climate trends suggest an important warm and humid tendency averaged over the southern plateau in annual period and in August. Moisture conditions would probably get drier at large area in the headwater region of the three rivers in annual average and months from April to November, and the northeast of the plateau from July to September. Complicated climatic trends over the Tibetan Plateau reveal that climatic factors have nonlinear relationships, and resulte in much uncertainty together with the scarcity of observation data. The results would enhance our understanding of the potential impact of climate change on environment in the Tibetan Plateau. Further research of the sensitivity and attribution of climate change to moisture conditions on the plateau is necessary.  相似文献   

8.
新疆极端降水的气候变化   总被引:92,自引:1,他引:91  
杨莲梅 《地理学报》2003,58(4):577-583
采用1961~2000年55个气象台站的逐日降水观测资料,分析近40年来新疆极端降水的气候变化、发展趋势和空间分布差异。用Mann-Kendall法对年极端降水量进行突变检验。研究表明:(1) 只有天山北麓经济带和天山南麓国家级棉花基地阿克苏地区极端降水量和频次有显著增多,尤以80年代以后明显,年极端降水量于1980年发生了气候突变,这种气候变化是由夏半年极端降雨量和频次增多导致的。(2) 新疆极端降水强度无显著变化,极端降水频次的显著增多导致极端降水量的显著增多。(3) 极端降水对年总降水量的贡献天山山区占年降水量的41.9%,北疆北部与和田区域极端降水的贡献为17.2%和21.9%,其它区域在25%~31.3%。年极端降水量距平与年降水量距平有好的相关关系 (除阿克苏地区和焉耆盆地外),说明极端降水量的变化导致年降水量的变化。  相似文献   

9.
杨振常  李玉霖  崔夺  陈静  赵学勇 《中国沙漠》2012,32(5):1384-1392
利用Penman-Monteith公式和常规气象资料计算和分析中国北方半干旱典型沙区(科尔沁沙地、浑善达克沙地和毛乌素沙地)50多年来主要气象要素和潜在蒸散量的变化趋势及其原因。 结果表明,自20世纪50年代以来,北方半干旱典型沙区年平均气温均呈上升趋势,年降水量均呈波动变化特征,但年平均风速呈明显下降的趋势。浑善达克沙地年潜在蒸散量随时间呈现显著增加趋势,科尔沁沙地年潜在蒸散量随时间呈现小幅的增加趋势,但毛乌素沙地年潜在蒸散量随时间呈现微弱的下降趋势。偏相关分析显示,毛乌素沙地潜在蒸散量与日照时数和风速呈显著的正相关,与平均温度呈显著的负相关;浑善达克沙地和科尔沁沙地潜在蒸散量与年平均温度显著正相关,但与日照时数无显著相关性。因此,毛乌素沙地日照时数减少和风速降低有可能是区域潜在蒸散量近几十年呈现减少的主要原因,科尔沁沙地和浑善达克沙地潜在蒸散量变化可能主要受温度的影响。  相似文献   

10.
通过内蒙古地区近46 a降水和潜在蒸散量以及湿润度在气温突变前后的倾向率和差值变化分析,得出该区域主要植被类型干湿环境演变的时空变化特征。研究结果表明:降水在气温突变前“东增西减”,突变后呈相反的变化趋势。46 a降水倾向率增加区域主要集中在呼伦贝尔市东部和乌兰察布市以西大部地区;潜在蒸散量在气温突变前呈减少趋势,突变后有增加趋势,突变后潜在蒸散量明显小于突变前。内蒙古46 a潜在蒸散量倾向率大部地区偏小,偏大区域仅存在于中东部偏北地区,气温突变后全区大部地区存在明显的“蒸发悖论”;大兴安岭西麓和乌兰察布市以西地区突变后湿润度增加明显,暖湿的气候环境有利于当地植被建设和生态恢复,内蒙古东南部、呼伦贝尔草原和锡林郭勒盟草原区有暖干化趋势,上述草原区存在潜在退化风险。  相似文献   

11.
基于InVEST模型的黑河流域上游水源涵养量   总被引:2,自引:1,他引:1  
黑河流域上游生态系统具有重要的水源涵养功能,对维系流域生态平衡有着重要的意义。基于InVEST模型估算了黑河流域上游水源涵养量,分析了水源涵养量的时空变化特征及其与气候因子的相关性。结果表明:2001—2015年黑河流域上游草地、林地、灌丛面积分别增加了1 665.00、381.75、162.75 km2,而荒漠和农田分别减少了2 165.25、20.50 km2;2001—2015年黑河流域上游水源涵养量年均值为228.64 mm,在空间上呈现东南高、西北低的分布特征,高值区位于祁连山一带,肃南裕固族自治县北部条带状为上游水源涵养量的低值区;从变化趋势来看,研究区水源涵养量以7.60 mm·a-1的速率减少;近15年来,研究区潜在蒸散、降水量分别呈现增加和减少趋势,速率分别为1.45、-0.67 mm·a-1,水源涵养与潜在蒸散以负相关为主,而与降水量正相关,降水量主要影响上游的中东部、北部的祁连山高寒地区,而潜在蒸散主要制约西北部的水源涵养量。  相似文献   

12.
刘闻  曹明明  邱海军  郭帅  李苒 《地理科学》2014,34(9):1145-1152
根据渭河流域关中段11个主要代表气象站点1955~2012年逐日气象数据,以FAO Penman-Monteith 公式得出潜在蒸发量,分析渭河流域关中段潜在蒸发量的时空变化特征。结果表明:① 渭河流域关中段年平均潜在蒸发量在1 073.9~1 284.1 mm,流域内多年平均蒸发量随着海拔的降低逐渐增高。② 夏季潜在蒸发量在327.6~547.2 mm,占全年的34%~42%,变化趋势与全年潜在蒸发量变化趋势高度一致。③ 渭河关中段随气温上升,潜在蒸发量减少。④ 年均潜在蒸发量与日较差、平均气温、平均风速、日照时数呈正相关,与相对湿度和水汽压呈负相关。  相似文献   

13.
1900-2007年横断山区部分海洋型冰川变化   总被引:12,自引:4,他引:8  
横断山区7条海洋型冰川近百年进退速度变化呈现出以退缩为总趋势的阶段性变化,具体表现为20世纪初至1930s的冰川稳定,1930s-1960s的冰川后退,1970s-1980s的冰川稳定或减速后退,20世纪80年代中期以来的冰川后退,这与我国、北半球及横断山区同期的气候变化呈明显对应,展现出冷干阶段冰川稳定或前进、暖湿阶段后退的态势,但各冰川的变化幅度因纬度位置、坡向、冰川规模、局地环境等而存在明显差异.1982/83年大、小贡巴冰川、海螺沟冰川冰舌段的消融水当量分别为2710mm、3139 mm和5281 mm,1990/91-97/98期间海螺沟冰川冰舌段的年均消融水当量为6157 mm,比1982/83年增加了876 mm.2002年夏季白水1号冰川的积雪消融量由于表碛覆盖较少表现出明显的随海拔升高而降低的特征,平均消融水当量为1086.25 mm,2008.9-19.10.13期间白水1号冰川物质平衡花竿的观测表明,花竿布设区域10月6号左右转入物质积累期.期间日均积累深为1cm,折合水当量5mm.  相似文献   

14.
近50 年雅鲁藏布江流域潜在蒸散量的变化特征   总被引:1,自引:0,他引:1  
采用1961-2010 年雅鲁藏布江流域6 个气象站近50 年逐日气温、气压等气象资料,利用Penman-Monteith (P-M) 模型计算了月、季及年的潜在蒸散量(PE),分析了雅江流域PE变化特征。研究表明:流域平均年、干季和湿季PE 呈微弱的增加趋势,增幅均在3.00 mm/10a 以下;PE的年代际变化表明20 世纪60 年代至80 年代,年PE有一个增加的过程,而后减少;雅江流域的PE在1981 年发生突变。  相似文献   

15.
辽宁省潜在蒸散发量及其敏感性规律分析   总被引:2,自引:0,他引:2  
曹永强  高璐  袁立婷  李维佳 《地理科学》2017,37(9):1422-1429
采用Penman-Monteith法和敏感系数法对辽宁省1965~2014年潜在蒸散发量及影响潜在蒸散发的气象因子敏感性进行分析,探讨气候变化下影响辽宁省潜在蒸散发量变化的主导因子及潜在蒸散发对气候变化的定量响应。结果表明:近50 a辽宁省潜在蒸散发呈现显著减少趋势,在空间上由西向东递减; 潜在蒸散发对气象因子的敏感性在年尺度上表现为,水汽压最为敏感,其次为太阳辐射、风速、平均气温;在季节尺度上,春季和秋季对平均气温最不敏感,夏季对风速最不敏感,冬季对太阳辐射最不敏感; 空间分布上,气象因素的敏感系数与气象因子空间变化规律相吻合,潜在蒸散发对气温的敏感性由北部向南部递增,对水汽压、太阳辐射的敏感性由东部向西部递减,而风速与之变化趋势相反。 风速的显著降低是辽宁省潜在蒸散发量下降的主要原因,太阳辐射的下降及水汽压的升高也促使了潜在蒸散发量的下降。  相似文献   

16.
近25年横断山区国土空间格局与时空变化研究   总被引:5,自引:0,他引:5  
时振钦  邓伟  张少尧 《地理研究》2018,37(3):607-621
横断山地提供多种生态系统服务,具有极高的生态价值,然而近年来面临人类活动强度增强所带来的国土空间可持续开发与管控挑战。利用横断山区1990年、2000年、2010年和2015年土地利用数据,分析不同海拔各种国土空间类型的数量、结构变化以及空间格局变化特征,揭示国土空间格局变化规律及影响因素。结果表明,横断山区国土空间海拔较高,垂直差异性明显,并且以生态空间为主体,生产、生活空间主要分布于东南部云南高原地区。25年间,三生空间变化加快且区域差异更突出,农业生产空间持续减少,工矿生产空间后十五年迅速增加,生活空间持续增加,生态空间波动增加。横断山区自然要素显著影响国土空间格局。西部大开发战略和退耕还林工程的实施明显带动横断山区国土空间格局变化。  相似文献   

17.
Trends of annual and monthly temperature, precipitation, potential evapotranspi-ration and aridity index were analyzed to understand climate change during the period 1971–2000 over the Tibetan Plateau which is one of the most special regions sensitive to global climate change. FAO56–Penmen–Monteith model was modified to calculate potential evapotranspiration which integrated many climatic elements including maximum and mini-mum temperatures, solar radiation, relative humidity and wind speed. Results indicate gen-erally warming trends of the annual averaged and monthly temperatures, increasing trends of precipitation except in April and September, decreasing trends of annual and monthly poten-tial evapotranspiration, and increasing aridity index except in September. It is not the isolated climatic elements that are important to moisture conditions, but their integrated and simulta-neous effect. Moreover, potential evapotranspiration often changes the effect of precipitation on moisture conditions. The climate trends suggest an important warm and humid tendency averaged over the southern plateau in annual period and in August. Moisture conditions would probably get drier at large area in the headwater region of the three rivers in annual average and months from April to November, and the northeast of the plateau from July to September. Complicated climatic trends over the Tibetan Plateau reveal that climatic factors have nonlinear relationships, and resulte in much uncertainty together with the scarcity of observation data. The results would enhance our understanding of the potential impact of climate change on environment in the Tibetan Plateau. Further research of the sensitivity and attribution of climate change to moisture conditions on the plateau is necessary.  相似文献   

18.
滹沱河上游山区近50年蒸散变化及主要影响因子分析   总被引:4,自引:0,他引:4  
准确估计流域蒸散,掌握其变化趋势和主要影响因子,对科学认识流域水文循环规律以及管理流域水资源具有重要意义。利用傅抱璞年蒸散量公式计算滹沱河上游山区及其子流域1958-2007年逐年蒸散量,并利用Mann-Kendall-Sneyers等方法分析了流域蒸散趋势和突变特征,及其主要影响因子。结果表明在滹沱河流域傅抱璞公式能够较好的拟合蒸散。50 a来全流域及各子流域年均蒸散呈下降趋势。降水对蒸散起控制作用,相对湿度在流域部分地区显著影响蒸散(α=0.05)。  相似文献   

19.
2000—2019年秦岭南北实际蒸散发时空变化特征   总被引:1,自引:0,他引:1  
基于遥感数据全面认识复杂地形单元实际蒸散发时空规律,对区域可持续水资源管理具有重要的意义。论文基于MODIS实际蒸散发(ET)数据,对2000—2019年秦岭南北ET时空变化特征进行分析,探究不同分区ET对植被变化的响应关系,进而识别ET趋势和年代变化的高相关海气环流因素。结果表明:① 在变化趋势上,以1000 m等高线为界,即秦岭地区北亚热带和山地暖温带的分界线,低海拔河谷地带为ET显著增加区,山地高海拔地区为ET下降区;② 除城市、乡镇周边地区,研究期间秦岭南北下垫面相对稳定,转为生态用地的活跃区主要分布在山地1000 m过渡带,其是ET与NDVI变化显著相关区,而1000 m以上高海拔地区两者相关性较低;③ ENSO、青藏高原北部气压异常,与秦岭山地、汉江谷地ET的趋势变化和年代波动显著相关,而西太平洋副热带高压与ET的趋势显著相关,与年代波动特征相关较弱。即发生中部型厄尔尼诺事件时,西太平洋副热带高压偏强,对流层低层形成异常反气旋,导致中国东部雨带北移,秦岭山地和汉江谷地降水偏少,气温偏高,ET往往偏大。研究结果启示:秦岭南北科学适应气候变化时,应关注秦岭山地、汉江谷地ET变化显著相关的环流信号;应深刻理解秦岭高海拔地区蒸散发下降趋势对区域水资源管理的影响。  相似文献   

20.
阿勒泰地区植被覆盖度及ET对气温变化的响应   总被引:1,自引:0,他引:1       下载免费PDF全文
韩飞飞  闫俊杰  郭斌 《干旱区地理》2019,42(6):1436-1444
研究气温对植被覆盖度和ET (Evapotranspiration,ET)的影响,对干旱区应对气候变化、维系生态系统稳定具有重要意义。基于阿勒泰地区及周边7个气象站,CRU数据集中的气温数据及MODIS ET数据,采用Mann-Kendall非参数检验、植被盖度反演等方法,对阿勒泰地区气温变化对植被覆盖度及ET的影响进行了研究。结果表明:(1)在1901—2016年过去的116 a间,阿勒泰地区年平均气温以0.18 ℃·(10 a)-1速率增加,在1982年由突变前的2.2 ℃增加到突变后的3.5 ℃。(2)2000—2017年阿勒泰地区植被覆盖度变化的空间差异明显,植被覆盖度增加的面积与降低的面积总体相当;全区66.71%的区域植被覆盖度变化与气温呈负相关,而呈正相关的比例仅占18.55%,且全区气温变暖而盖度降低区域的占比达31.71%。(3)2000—2016年阿勒泰地区ET总体呈降低趋势,整个区域61.65%的面积温度降低、ET降低,而19.92%的区域表现为温度增加而植被ET降低。  相似文献   

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