Water Resources Research Act Program

Details for Project ID 2017DC192B

Quantifying the Recharge and Evapotranspiration Rates of the Chesapeake Bay Watershed using Land Surface State Observations

Institute: District of Columbia
Year Established: 2017 Start Date: 2017-03-01 End Date: 2018-02-28
Total Federal Funds: $9,929 Total Non-Federal Funds: $20,104

Principal Investigators: Leila Farhadi

Abstract: Recharge to the aquifers and evapotranspiration from the landscape are two critical fluxes in water cycle that are most sensitive to human alteration of landscape. As a result these fluxes have already changed dramatically in the historical era and by orders of magnitude. Fields of diffusive recharge flux and evapotranspiration play a pivotal role in (1) the global water, energy and biogeochemical cycles, (2) the sustainability of aquifers; (3) crop productivity; (4) ecosystem health and (5) climate. Evapotranspiration and recharge can amplify changes in precipitation and radiative forcing resulting from climate change. Small changes in the magnitude, seasonality and intermittency of precipitation and radiation can be magnified in the recharge and evapotranspiration signals. As a result, the future of these two critical fluxes under a changing atmospheric composition may be even more uncertain. Despite the importance of these fluxes and their historical change, there are no direct measurements – in situ or by remote sensing - that can allow any mapping or any global or regional estimation. The objective of this study is to develop and integrate state-of- the-art computational and data assimilation techniques that enable the quantification and mapping of the evapotranspiration and recharge flux using spaceborne and airborne remote sensing measurements of land surface state variables. The ultimate goal is to quantify these fluxes over the Chesapeake bay watershed at spatial scales of several hundred meters to several kilometers (order 0.1–10 km) and temporal scales of 1–3 days, relevant to the current and foreseeable range of applications in water resources and operational weather and climate predictions. In the proposed research proposal, the feasibility of the developed approach will be tested at point scale using field site measurements within a small drainage basin in the Anacostia river watershed.