三江源2003~2020年地下水储量变化分析

利用时变重力场模型、GLDAS水文模型和湖泊水量变化数据反演三江源区域2003~2020年地下水储量变化，使用奇异谱分析方法对地下水变化时间序列进行分析。结果表明，2003~2012年三江源区域地下水储量整体呈现增长趋势，年增长率为0.7 cm/a；2013~2020年三江源区域地下水储量整体呈现减少趋势，年增长率为-0.3 cm/a；三江源区域地下水年度变化主要受降雨补给规律的影响，降雨对地下水的补给滞后期为2个月。

Analysis on the Variation of Groundwater Storage in Three-River Headwater Region from 2003 to 2020

We use the time-varying gravity field model,the GLDAS hydrological model and lake water volume change data to invert the changes in groundwater storage in the Three-River headwater region from 2003 to 2020.We extract the trend and periodic changes of groundwater storage through singular spectrum analysis.The result shows that from 2003 to 2012,the groundwater storage in the Three-River headwater region showed an overall increasing trend,with an annual growth rate of 0.7 cm/a;from 2013 to 2020 the groundwater storage in the Three-River headwater region showed a decreasing trend,with an annual growth rate of-0.3 cm/a.The annual variation of groundwater storage in the Three-River headwater region is mainly affected by rainfall replenishment,which lags behind the recharge of groundwater by rainfall by two months.