Ecosystem Resiliency Study under Extreme Droughts using Multi-Land Surface Models

Thursday, 18 December 2014
Liyi Xu1, C Adam Schlosser1, David W Kicklighter2, Kyaw Tha Paw U3, Kuang-Yu Chang3, Benjamin S Felzer4 and Zavareh Kothavala4, (1)Massachusetts Institute of Technology, Cambridge, MA, United States, (2)MBL, The Ecosystems Center, Woods Hole, MA, United States, (3)University of California Davis, Davis, CA, United States, (4)Lehigh University, Bethlehem, PA, United States
This study investigates the hydrological response of ecosystem to droughts of different time scales and magnitudes. Four land surface models with different bio-geophysical parameterizations and representations are used to simulate evapotranspiration and carbon dioxide fluxes during these extreme events. The Terrestrial Ecosystem Model (TEM) is a process-based ecosystem model that uses spatially referenced information on climate, elevation, soils, vegetation and water availability to make monthly estimates of vegetation and soil carbon and nitrogen fluxes and pool sizes. There are two versions of TEM model, the TEM-Hydro daily model and the TEM monthly model. The Advanced Canopy-Atmosphere-Soil Algorithm (ACASA) is a multi-layered land surface model based on eddy-covariance theory to calculate the biosphere-atmosphere exchanges of carbon dioxide, water, and momentums. The Community Land Model (CLM) is a community-based model consists of biogeophysics, hydrological cycle, biogeochemistry and dynamic vegetation. Model simulations are evaluated using the biogeophysical and micrometeorological field observations from the AmeriFlux sites across the US.