Quantifying Water Budgets in Amazonian Watershed Using a Coupled Subsurface - Land Surface Process Model

Amazonian tropical ecosystems cycle large amounts of CO2 and water. The influence of climate change on the interactions between Amazonian hydrologic and carbon cycles are uncertain and therefore an important research topic. We examine water budget components in a regional watershed in the central Amazon basin, using remotely sensed data and a process-based adaptive watershed simulator (PAWS) coupled with the community land model (CLM). The coupled model (PAWS+CLM) includes detailed representations of subsurface and land surface hydrologic processes. We use stream flow discharge observations and satellite-based estimates of evapotranspiration (Moderate-resolution Imaging Spectroradiometer, MODIS) to evaluate model performance. We compute the fluxes of evapotranspiration, surface runoff, recharge, and groundwater contributions to streams using the PAWS+CLM simulations.