基于GRACE重力卫星的珠江流域陆地水储量时空变化研究

Spatiotemporal Changes of Terrestrial Water Storage in the Pearl River Basin Based on GRACE Data

在气候变化及人类活动日益剧烈的背景下,研究流域陆地水资源变化对理解水文循环过程和管理水资源具有重要意义。基于GRACE重力卫星数据研究了珠江流域2002~2017年陆地水储量异常(TWSA)的时空变化特征。结果表明:五套官方GRACE数据在珠江流域的相关性极强,且与GLDAS模拟值及各水文通量变化一致;珠江流域的TWSA呈现显著上升趋势,中游和下游北部增长速度最快,达7.9~10.2mm/a;空间上,各栅格的TWSA均表现出明显的季节性特征,且振幅从南到北、从西到东逐渐下降,除了个别年份,TWSA与实测降雨的空间质心体现了一致的分布和运动特点。GRACE数据在珠江流域具有较高适用性。

With intensifying climate change and human activities,detecting the spatial and temporal variation of terrestrial water storage in basin scale is of great significance for understanding the hydrological cycle and managing water resources.Based on GRACE data,this paper studied the temporal and spatial change characteristics of terrestrial water storage anomaly(TWSA)in the Pearl River basin from 2002 to 2017.The results show that:five GRACE products present strong correlation in the basin,and are consistent with GLDAS-simulated multiply hydrological fluxes;TWSA shows a significant upward trend.The middle reaches and the northern part of the lower reaches have the fastest growth rate of 7.9-10.2mm/a;Spatially,TWSA of each grid illustrates obvious seasonal characteristics,and the amplitude gradually decreases from south to north and west to east,respectively.The centroids of TWSA and in-situ rainfall reflect similar spatial distribution and movement characteristics.GRACE data show high applicability in the basin.