Recent global decline in endorheic basin water storage and its implications for the water cycle
Abstract
Endorheic (i.e., hydrologically landlocked) basins spatially concur with arid and semiarid climates. Given limited precipitation but high potential evaporation, their water storage is vulnerable to subtle flux perturbations, which are exacerbated by global warming and human activities. Increasing regional evidence suggests a likely recent net decline in endorheic water storage, but this remains unquantified at a global scale. By integrating satellite observations and hydrological modeling, we reveal that during 2002-2016, the global endorheic system experienced a widespread water loss of about 106 Gt per year, attributed to comparative losses in surface water, soil moisture, and groundwater. This decadal decline, disparate from water storage fluctuations in exorheic basins, appears less sensitive to ENSO-driven climate variability, implying possible responses to longer-term climate conditions and human water management. In the mass-conserved hydrosphere, such an endorheic water loss not only exacerbates local water stress, it also imposes excess water on exorheic basins, leading to a maximal sea level rise that matches the contribution of nearly half of the land glacier retreat (excluding Greenland/Antarctica). Given these dual ramifications, we suggest the necessity of long-term monitoring of water storage variation in the global endorheic system and inclusion of its net contribution to future sea level budgeting.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.H13G..02W
- Keywords:
-
- 1809 Desertification;
- HYDROLOGY;
- 1812 Drought;
- HYDROLOGY;
- 1833 Hydroclimatology;
- HYDROLOGY;
- 1834 Human impacts;
- HYDROLOGY