摘要
通过构建基于重力卫星的实际蒸散发重建方法来获取高精度的实际蒸散发信息,为研究气候变化下的水循环规律提供关键信息。利用GLDAS陆面模式同化数据对GRACE重力卫星水储量观测数据进行空间降尺度,通过水量平衡法,重建了金沙江流域2002—2016年的子流域尺度实际蒸散发月序列。结果表明:①基于重力卫星观测与水量平衡方法重建的实际蒸散发(ET Recon)与ET PLSH、ET Jung和ET MODIS 3种遥感反演产品相比有较高的可靠性,其中与ET PLSH的相关性最高(r=0.82),与ET Jung的平均差和均方根差最小。②研究区年均实际蒸散发为410.8 mm/a,空间分布上由西北向东南递增,年际变化上呈增加趋势。③季节尺度上,实际蒸散发夏季最高,呈逐年增加趋势;冬季最低,波动较平稳。
To obtain a high-quality record of actual evapotranspiration(ET A)with which to investigate water cycle changes in the context of climate change,this study developed a method for reconstruction of ET A based on gravity satellite observations.The proposed method used GLDAS assimilated land surface water storage data to downscale GRACE equivalent water thickness to finer spatial resolution.Then,subbasin-level monthly ET A data for the Jinshajiang River basin were reconstructed based on the water balance during 2002—2016.Results showed that:①The reconstructed ET A data(ET Recon)had high quality and compared well with three satellite-retrieval products,i.e.,ET PLSH,ET Jung,and ET MODIS;the strongest correlation was with the ET PLSH product(r=0.82)and the lowest root mean squared difference was with the ET Jung data.②Multiyear mean ET A in the study area was 410.8 mm/a with a gradient of increase from northwest to southeast.Temporally,it showed a significant upward trend during 2002—2016.③Seasonally,summer ET A was highest and it showed an upward trend over the study period;conversely,ET A in winter had the lowest value and it showed trivial change temporally.
作者
张珂
鞠艳
李致家
ZHANG Ke;JU Yan;LI Zhijia(State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China;College of hydrology and Water Recourses,Hohai University,Nanjing 210098,China)
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2021年第2期182-191,共10页
Advances in Water Science
基金
国家重点研发计划资助项目(2016YFC0402701)
江苏省杰出青年基金资助项目(BK20180022)。
关键词
实际蒸散发
GRACE卫星
水量平衡
时空分布
金沙江流域
actual evapotranspiration
GRACE satellite
water balance
spatiotemporal distributions
Jinshajiang River basin
