Evaluating the Amazon water cycle components using ED model against GRACE

Tuesday, 16 December 2014: 5:15 PM
Eunjee Lee1, Shin-Chan Han2, In-Young Yeo3, Marcos Longo4, Abigail L. S. Swann5, Ryan G Knox6, John Briscoe1 and Paul R Moorcroft1, (1)Harvard University, Sustainability Science Program, Kennedy School of Government, Cambridge, MA, United States, (2)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (3)University of Maryland, College Park, MD, United States, (4)EMBRAPA Brazilian Agricultural Research Corportation, Campinas, Brazil, (5)University of Washington, Atmospheric Sciences, Seattle, WA, United States, (6)Lawrence Berkeley National Laboratory, Berkeley, CA, United States
Changes in the water cycle components of the Amazon and its surrounding regions are a key to assessing regional impacts of climate and land-cover changes, as they may affect rain-fed agriculture and hydroelectric power generation in Brazil. A comprehensive validation of the modeled water budget, therefore, is a necessary part of understanding the region’s hydroclimatology. We evaluate the water cycle components from Ecosystem Demography (ED) model both as a stand-alone model and a coupled model to the Brazilian Regional Atmospheric Modeling System (BRAMS). Model results are compared with satellite-driven observations and a flux tower measurement in central Amazon. Our results indicate that the modeled EDBRAMS precipitation over Amazonia replicates the observed patterns of the Tropical Rainfall Measuring Mission (TRMM) from 2001 to 2009. Total Water Storage Change (TWSC) anomalies from the ED model at the Paraná River basin shows a better agreement with the Gravity Recovery And Climate Experiment (GRACE) satellite observation from 2002 to 2008, as compared to the Global Land Data Assimilation System (GLDAS)/NOAH model. The Nash-Sutcliff model efficiency coefficient improved from 0.50 (GLDAS/NOAH vs. GRACE) to 0.65 (ED vs. GRACE). We also evaluate the modeled evapotranspiration (ET) against the flux tower measurement. Our study affirms the capabilities of the ED model in simulating the Amazon hydrological cycle, which helps investigate its sustainable thresholds with various land-cover and climate change scenarios.