利用重力卫星监测中国西南地区陆地水储量变化

Variation of Terrestrial Water Storage Changes in the Southwest China Monitored by Gravity Satellite

如何实现可持续大范围地陆地水储量监测一直是水资源管理的研究热点。基于2003—2015年共计13年的重力恢复与气候实验(gravity recovery and climate experiment,GRACE)月重力场模型,采用组合滤波削弱重力场数据误差,并扣除冰后回弹的影响,实现对中国西南地区陆地水储量变化的持续监测,并与同期GLDAS(global land data assimilation system)水文模型结果进行比较。研究结果表明:GRACE能够有效地实现大范围内的陆地水储量变化的可持续监测,2003—2015年间出现了三次异常低值,分别为2004年、2010年和2014年;同时,还能有效监测2009—2010年西南地区干旱事件发生、扩展和结束三个阶段的时空变化情况。

How to achieve sustainable large-scale monitoring of terrestrial water storage has always been a research hotpot in water resource management.Based on GRACE(gravity recovery and climate experiment)monthly gravity filed model,a combined filter was applied for continuously monitoring the terrestrial water storage from 2003—2015 variation in southwest of China,in which errors in gravity field data was reduced and the impact of post-glacial rebound was deducted;and the calculation results were compared with those of GLDAS(global land data assimilation system)hydrological model over the same period.Results show that the change of te-rrestrial water reserves could be sustainably monitored in a wide range by GRACE.Three abnormal low values that occurred in 2004,2010,and 2014,were revealed.In addition,three stages of drought event in Southwest China from 2009 to 2010 were distinguished in spatial and temporal variation were recognized from the occurrence,expansion,and termination.