EGU21-8578, updated on 31 May 2023
https://doi.org/10.5194/egusphere-egu21-8578
EGU General Assembly 2021
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Estimating water change at Earth's surface using GRACE gravity and GPS positioning: Inferring groundwater change in the United States

Donald Argus1, David Wiese1, Hilary Martens2, Mackenzie Anderson3, Athina Peidou1, Matthias Elmer1, Adrian Borsa4, El Knappe4, and Felix Landerer1
Donald Argus et al.
  • 1Jet Propulsion Laboratory, Space Geodesy and Geodynamics, Pasadena, United States of America (donald.f.argus@jpl.nasa.gov)
  • 2University of Montana, Missoula
  • 3University of California, Los Angeles
  • 4Scripps Institute of Oceanography, University of California, San Diego

We estimate change in total water and its components each month from January 2006 to the Present using geodetic observations from space and complementary hydrologic measurements.  Estimates of changes in total water inferred from GPS elastic displacements are used to strengthen the spatial resolution of GRACE observations of mass change, resulting in sharper images of water change.  We furthermore distinguish between different components of water change.  Change in surface water in man's artificial reservoirs and natural lakes are known from gauging measurements of water levels.  The distribution and magnitude of snow accumulation is inferred from sticks and scales on the ground.  We remove the effect of surface water and snow to infer change in water in the ground, consisting of soil moisture and groundwater.  This determination is bringing powerful insights into understanding the water cycle.  We are finding more water to be lost during drought and gained during heavy precipitation than in the hydrology models, suggesting that the hydrology models must be revised to have a greater capacity to store water in the ground.  Not all rain and melting snow that falls on the mountains of California, Oregon, and Washington is found to runoff into rivers taking water to the ocean.  Rain and melting snow is instead found to infiltrate the ground in the wet fall and winter and and to be parched from the ground in the dry spring and summer.

 

How to cite: Argus, D., Wiese, D., Martens, H., Anderson, M., Peidou, A., Elmer, M., Borsa, A., Knappe, E., and Landerer, F.: Estimating water change at Earth's surface using GRACE gravity and GPS positioning: Inferring groundwater change in the United States, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-8578, https://doi.org/10.5194/egusphere-egu21-8578, 2021.