The objective of this project is to estimate global recharge, which remains one of the least understood components of the water cycle. But there are recent promising results using smap observations to…

Georgia TECH Research Corp, operating through its Office of Sponsored Programs, received a $445,128 research grant from a civilian federal agency with an ultimate completion date of October 6, 2027. This award supports research to advance understanding of global groundwater recharge, one of the least comprehended components of the hydrological cycle. The project aims to validate the use of SMAP (Soil Moisture Active Passive) satellite observations to estimate seasonal and monthly recharge rates in regions with deep water tables, which represent approximately 80% of Earth's land surface, and to expand this methodology to estimate net recharge in areas with shallow water tables where capillary-driven upward water movement must be accounted for alongside gravitational downward fluxes.

The grant carries no set-aside designation, indicating open competition for the award. As a leading research institution and the primary research entity of the Georgia Institute of Technology, Georgia TECH Research Corp brings substantial experience in federal research execution across multiple scientific domains. The work will be performed in Atlanta, Georgia, and represents part of the organization's broader portfolio of federally funded research spanning environmental science, engineering, and advanced technology development supported by agencies including the National Science Foundation, NASA, and the Department of Energy.

The objective of this project is to estimate global recharge, which remains one of the least understood components of the water cycle. But there are recent promising results using smap observations to estimate recharge in locations with deep water table at an annual time scale. With the above in mind, the goals of this proposal are to:.1. Confirm the validity of estimating recharge from smap observations globally at the seasonal and/or monthly time scales in regions with deep water tables, which is the situation in 80% of the earth's land surface.2. Expand the methodology to estimate net recharge, globally, in regions where the water table is shallow, and the recharge is the net of upward fluxes (exfiltration driven by capillarity) and gravity-dominated downward fluxes.