摘要
基于MOD16全球蒸散发产品和气象站点实测数据,运用变异系数法、Sen趋势法等研究了山西省2000-2014年地表蒸散发ET、潜在蒸散发PET的空间分布特征、变化趋势及影响因素。结果表明:①MOD16蒸散产品与气象站点实测蒸散发之间具有良好的时空相关性(R^2=0.90),其产品精度可以满足山西省蒸散发时空分布研究的要求;②山西省多年平均ET、PET分别为816.77、1608.46 mm,年内变化表现为先增高后下降的"单峰"型分布,二者差值在5月、6月最大,此时山西省最为干旱;③全省年平均ET呈现西北低、东南高的分布特征,PET呈西南高、东北低的分布特征,二者差值整体上较大,表现为全省地表水分比较缺乏,其中忻州、吕梁西部最为严重;④全省近15 a来ET和PET的年际变化都比较小,整体上全省PET在增加,ET在相对减少,意味着近15 a来干旱情况在加剧;⑤ET、PET的时空变化与诸多气象因子相关,在空间尺度上与降水、相对湿度密切相关,在时间尺度上与气温、降水关系最为密切。
Based on the MODIS evapotranspiration(ET) products(MOD 16) and the observation data of meteorological stations, coefficient of variation method and Sen+Mann-Kendall model were used to analyze the spatiotemporal feature, variation trends, and influencing factors of land surface ET and potential evapotranspiration(PET) in Shanxi Province from 2000 to 2014. The main conclusions are as follows: 1) The accuracy of the MOD16-ET(R^2=0.9) of Shanxi can meet the requirements of such research, and can be used to examine the spatiotemporal distribution of surface ET. 2) The mean annual ET and PET were 816.77 mm and1608.46 mm, respectively. The annual distribution showed a unimodal pattern, which increased first and then decreased;the difference between ET and PET was the largest in May and June when it was the driest in the study area. 3) The annual average ET of the study area was low in northwest Shanxi and high in southeast, while the annual average PET was high in southwest and low in northeast of the study area. The overall difference between the annual average ET and PET was relatively large, which reflects that the whole province was shortage of water, especially in Xinzhou and the west of Lvliang. 4) The interannual variations of ET and PET have been relatively small in the past 15 years. Evapotranspiration showed a decreasing trend, and PET showed an increasing trend, which suggest that the drought was aggravated in Shanxi in the past 15 years. 5) The correlation analysis between evapotranspiration and meteorological factors indicated that the spatiotemporal variation of evapotranspiration was closely related to many climatic factors-they were related to precipitation and relative humidity spatially, and were most closely related to temperature and precipitation temporally.
作者
温媛媛
赵军
王炎强
王玉纯
王建邦
WEN Yuanyuan;ZHAO Jun;WANG Yanqiang;WANG Yuchun;WANG Jianbang(College of Geography and Environment Sciences,Northwest Normal University,Lanzhou 730070,China)
出处
《地理科学进展》
CSSCI
CSCD
北大核心
2020年第2期255-264,共10页
Progress in Geography
基金
国家自然科学基金项目(41661084)。
关键词
蒸散发
潜在蒸散发
时空分布
MOD16
山西省
evapotranspiration
potential evapotranspiration
spatiotemporal distribution
MOD16
Shanxi Province
