As observed by the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow On (GRACE-FO) missions, global terrestrial water storage (TWS), excluding ice sheets and glaciers, declined rapidly between May 2014 and March 2016. By 2023, it had not yet recovered, with the upper end of its range remaining 1 cm equivalent height of water below the upper end of the earlier range. Beginning with a record-setting drought in northeastern South America, a series of droughts on five continents helped to prevent global TWS from rebounding. While back-to-back El Niño events are largely responsible for the South American drought and others in the 2014–2016 timeframe, the possibility exists that global warming has contributed to a net drying of the land since then, through enhanced evapotranspiration and increasing frequency and intensity of drought. Corollary to the decline in global TWS since 2015 has been a rise in barystatic sea level (i.e., global mean ocean mass). However, we find no evidence that it is anything other than a coincidence that, also in 2015, two estimates of barystatic sea level change, one from GRACE/FO and the other from a combination of satellite altimetry and Argo float ocean temperature measurements, began to diverge. Herein, we discuss both the mechanisms that account for the abrupt decline in terrestrial water storage and the possible explanations for the divergence of the barystatic sea level change estimates.

根据重力恢复和气候实验 （GRACE） 和 GRACE 后续 （GRACE-FO） 任务的观测，2014 年 5 月至 2016 年 3 月期间，不包括冰盖和冰川在内的全球陆地水储量 （TWS） 迅速下降。到 2023 年，它还没有恢复，其范围的上限仍然比之前范围的上限低 1 厘米的水位当量高度。从南美洲东北部创纪录的干旱开始，五大洲的一系列干旱帮助阻止了全球 TWS 的反弹。虽然连续的厄尔尼诺事件是造成 2014-2016 年南美干旱和其他干旱的主要原因，但全球变暖有可能通过增加蒸散和增加干旱的频率和强度，导致自那时以来土地净干涸。自 2015 年以来，全球 TWS 下降的必然结果是重静态海平面（即全球平均海洋质量）的上升。然而，我们没有发现任何证据表明，同样在 2015 年，两个重静态海平面变化的估计值开始出现分歧，一个来自 GRACE/FO，另一个来自卫星测高和 Argo 浮标海洋温度测量的组合，这只不过是巧合。在本文中，我们讨论了导致陆地水储量突然下降的机制，以及重静态海平面变化估计值分歧的可能解释。