A Remote Sensing Data Assimilation Strategy for Ungaged Basins

E.F. Wood (1), J. Sheffield (1), M. Pan (1), H. Su (1)

(1) Princeton University, Dept. Civil and Environmental Eng., Princeton, NJ 08544 United States.

The IAHS initiative Prediction in Ungauged Basins (PUB) addresses a long standing scientific challenge for hydrology: the estimation of water fluxes and states for catchments with insufficient ground-based gauging. PUB has been motivated in part from the decline in ground networks over much of the developing countries, as well as the need to better understand the water and energy budget at regional to continental scales for better understanding of water sustainability under changing demands and climates, and for water cycle research. While ground based networks have declined, the increase in remotely sensed hydrologic data has increased dramatically over the last few years, with additional data imminently available from recently launched satellites. These satellites include NASA's Earth Observing System Terra and Aqua, NASDA's ADEOS-II, and ESA's Envisat. These platforms include a suite of VIS-IR and microwave radiometers that are appropriate for water cycle research. In this presentation a strategy is presented on how these remotely sensed data, combined with hydrologic modeling through data assimilation can be used to estimate water budget terms over ungauged catchments.