利用 GRACE 卫星分析安徽省地下水储量的时空变化

文章利用重力恢复与气候实验卫星(Gravity Recovery and Climate Experiment, GRACE)时变重力场球谐系数文件,联合全球陆面数据同化系统(Global Land Data Assimilation System, GLDAS)水文模型反演安徽省2003—2016年地下水储量的时空变化。通过奇异谱分析(Singular Spectrum Analysis, SSA)地下水时间序列,结合热带降雨测量任务(Tropical Rainfall Measuring Mission, TRMM)降雨数据对地下水储量变化规律进行分析。结果表明,安徽省地下水储量在2011年和2014年前后发生较大变化,在2003—2011年的变化率为0.37 cm/a,2011—2014年的下降速率为-0.2 cm/a,2014—2016年的增长速率为1.9 cm/a;进一步与降雨数据关联,发现降雨量是影响安徽省地下水储量年际变化和季节性变化的主要因素。在空间上,安徽省呈现自东北向西南逐渐缓和的趋势,最大亏损出现在皖北地区,为-7.52 mm/a,在西南地区的最大盈余达到8.38 mm/a。

In this paper, Gravity Recovery and Climate Experiment (GRACE) time-varying gravity field spherical harmonic coefficient files, combined with Global Land Data Assimilation System (GLDAS) hydrological model are used to invert the spatial and temporal variation of groundwater storage in Anhui Province from 2003 to 2016. Groundwater time series are analyzed by singular spectrum analysis (SSA) and then combined with Tropical Rainfall Measuring Mission (TRMM) precipitation data, the variation patterns of the groundwater storage are analyzed. The results show that the groundwater storage in Anhui Province changed significantly in 2011 and 2014, with a rate of change of 0.37 cm/a from 2003 to 2011, a rate of decrease of -0.2 cm/a from 2011 to 2014, and a rate of increase of 1.9 cm/a from 2014 to 2016. Further study reveals that precipitation is the main factor affecting interannual and seasonal variation of groundwater storage in Anhui Province. Spatially, Anhui Province shows a gradual moderating trend from northeast to southwest, with the maximum deficit appearing in northern Anhui at -7.52 mm/a and the maximum surplus in southwest Anhui reaching 8.38 mm/a.