CLMT2 user's guide: A Coupled Model for Simulation of HydraulicProcesses from Canopy to Aquifer Version 1.0

Pan, Lehua

Lawrence Berkeley National Laboratory

关键词: Meteological Drive Forcing Surface And Subsurface Hydrologycoupling Clm3 And Tough2;    Saturation;    Surface Energy;    58;    Evaporation;   

DOI  :  10.2172/900656
RP-ID  :  LBNL--60857
RP-ID  :  DE-AC02-05CH11231
RP-ID  :  900656

美国|英语

来源: UNT Digital Library

【 摘 要 】

CLMT2 is designed to simulate the land-surface andsubsurface hydrologic response to meteorological forcing. This modelcombines a state-of-the-art land-surface model, the NCAR Community LandModel version 3 (CLM3), with a variably saturated groundwater model, theTOUGH2, through an internal interface that includes flux and statevariables shared by the two submodels. Specifically, TOUGH2, in itssimulation, uses infiltration, evaporation, and root-uptake rates,calculated by CLM3, as source/sink terms; CLM3, in its simulation, usessaturation and capillary pressure profiles, calculated by TOUGH2, asstate variables. This new model, CLMT2, preserves the best aspects ofboth submodels: the state-of-the-art modeling capability of surfaceenergy and hydrologic processes from CLM3 (including snow, runoff,freezing/melting, evapotranspiration, radiation, and biophysiologicalprocesses) and the more realistic physical-process-based modelingcapability of subsurface hydrologic processes from TOUGH2 (includingheterogeneity, three-dimensional flow, seamless combining of unsaturatedand saturated zone, and water table). The preliminary simulation resultsshow that the coupled model greatly improved the predictions of the watertable, evapotranspiration, and surface temperature at a real watershed,as evaluated using 18 years of observed data. The new model is also readyto be coupled with an atmospheric simulation model, representing one ofthe first models that are capable to simulate hydraulic processes fromtop of the atmosphere to deep-ground.