A comparison is presented between groundwater storage trends derived from Gravity Recovery and Climate Experiment (GRACE) satellite measurements and trends derived from unregulated river baseflow observations in 19 catchments in tributaries of the Central Yangtze River. The two sets of trends are well correlated with a coefficient of r = 0.64, but the baseflow‐derived trends were found to be on average about 33% smaller than those based on the GRACE measurements. Although other factors undoubtedly play a role, the difference in trend magnitudes of the two sets of trends is concluded to be mainly due (i) to remaining uncertainties and complexities in GRACE data processing and (ii) to the likely gradual shrinking of the contributing catchment areas during the baseflow recession process. The present findings should be useful in extending GRACE measurements to longer periods on the basis of long‐term streamflow measurements and in recovering missing data.

中文翻译：

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长江中下游地区GRACE和基流衰退引起的地下水储量变化的相互一致性

比较了重力恢复和气候实验（GRACE）卫星测量得出的地下水储藏趋势与长江中下游支流19个流域未经监管的河流底流观测值得出的趋势。两组趋势与系数r密切相关 = 0.64，但发现基流派生的趋势平均比基于GRACE测量的趋势小33％。尽管其他因素无疑发挥了作用，但得出的结论是，两组趋势的趋势量的差异主要是由于（i）GRACE数据处理中仍然存在不确定性和复杂性，以及（ii）贡献集水区可能逐渐缩小基流衰退过程中的区域。在长期流量测量的基础上，本发明的发现对于将GRACE测量扩展到更长的时间和恢复丢失的数据应该是有用的。