Assessing meteorological and hydrological drought in the western US using geodesy
Abstract
More than half of the western US experienced extreme or exceptional drought conditions in 2021. With changes in climate and increasing demands on water resources, drought conditions are likely to intensify in coming years, making accurate estimates of total water storage and distribution more critical. Advances in space geodesy, including Global Navigation Satellite Systems (GNSS) and the Gravity Recovery and Climate Experiment (GRACE), provide novel opportunities to track and manage valuable freshwater resources by observing load-induced changes in Earths shape. Deformation of the solid Earth caused by the weight of water reveals important information about fluctuations in terrestrial water storage, both within surface and subsurface reservoirs. Here, we compare GNSS and GRACE inferences of water-storage changes with precipitation data and hydrological models in the western US. The geodetic data indicate that more water remains stored in the ground than is indicated by surface hydrology models, which can shed light on the lag time between precipitation deficits (meteorological drought) and the parching of water from ground, soil, and surface reservoirs (hydrological drought). By placing tighter constraints on water-resource availability using geodesy, we aim to improve hydrological models for water-resource management and to advance understanding of Earths water cycle and climate.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.G55A0240M