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Title: Modeling Hydraulic Responses to Meteorological Forcing: fromCanopy to Aquifer

Abstract

An understanding of the hydrologic interactions amongatmosphere, land surface, and subsurface is one of the keys tounderstanding the water cycling system that supports our life system onearth. Properly modeling such interactionsis a difficult task because oftheinherent coupled processes and complex feedback structures amongsubsystems. In this paper, we present a model that simulates thelandsurface and subsurface hydrologic response to meteorological forcing.This model combines a state of the art landsurface model, the NCARCommunity Land Model version 3 (CLM3), with a variablysaturatedgroundwater model, the TOUGH2, through an internal interfacethat includes flux and state variables shared by the two submodels.Specifically, TOUGH2, in its simulation, uses infiltration, evaporation,and rootuptake rates, calculated by CLM3, as source/sink terms? CLM3, inits simulation, uses saturation and capillary pressure profiles,calculated by TOUGH2, as state variables. This new model, CLMT2,preserves the best aspects of both submodels: the state of the artmodeling capability of surface energy and hydrologic processes from CLM3and the more realistic physical process based modeling capability ofsubsurface hydrologic processes from TOUGH2. The preliminary simulationresults show that the coupled model greatly improves the predictions ofthe water table, evapotranspiration, surface temperature, and moisture inthe top 20 cm of soil at a real watershed, as evaluated from 18 years ofobserved data. Themore » new model is also ready to be coupled with anatmospheric simulation model, representing one of the first models thatare capable to simulate hydraulic processes from top of the atmosphere todeep ground.« less

Authors:
; ; ; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE
OSTI Identifier:
932469
Report Number(s):
LBNL-61018
R&D Project: 366176; BnR: YN0100000; TRN: US200813%%65
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Vadose Zone Journal; Journal Volume: 7; Related Information: Journal Publication Date: 2008
Country of Publication:
United States
Language:
English
Subject:
58; 54; 42; AQUIFERS; EVAPORATION; FEEDBACK; HYDRAULICS; MOISTURE; SATURATION; SIMULATION; SOILS; SURFACE ENERGY; WATER; WATER TABLES; surface-subsurface interaction numerical modeling TOUGH2CLM

Citation Formats

Pan, Lehua, Jin, Jiming, Miller, Norman, Wu, Yu-Shu, and Bodvarsson,Gudmundur. Modeling Hydraulic Responses to Meteorological Forcing: fromCanopy to Aquifer. United States: N. p., 2007. Web.
Pan, Lehua, Jin, Jiming, Miller, Norman, Wu, Yu-Shu, & Bodvarsson,Gudmundur. Modeling Hydraulic Responses to Meteorological Forcing: fromCanopy to Aquifer. United States.
Pan, Lehua, Jin, Jiming, Miller, Norman, Wu, Yu-Shu, and Bodvarsson,Gudmundur. Thu . "Modeling Hydraulic Responses to Meteorological Forcing: fromCanopy to Aquifer". United States. doi:. https://www.osti.gov/servlets/purl/932469.
@article{osti_932469,
title = {Modeling Hydraulic Responses to Meteorological Forcing: fromCanopy to Aquifer},
author = {Pan, Lehua and Jin, Jiming and Miller, Norman and Wu, Yu-Shu and Bodvarsson,Gudmundur},
abstractNote = {An understanding of the hydrologic interactions amongatmosphere, land surface, and subsurface is one of the keys tounderstanding the water cycling system that supports our life system onearth. Properly modeling such interactionsis a difficult task because oftheinherent coupled processes and complex feedback structures amongsubsystems. In this paper, we present a model that simulates thelandsurface and subsurface hydrologic response to meteorological forcing.This model combines a state of the art landsurface model, the NCARCommunity Land Model version 3 (CLM3), with a variablysaturatedgroundwater model, the TOUGH2, through an internal interfacethat includes flux and state variables shared by the two submodels.Specifically, TOUGH2, in its simulation, uses infiltration, evaporation,and rootuptake rates, calculated by CLM3, as source/sink terms? CLM3, inits simulation, uses saturation and capillary pressure profiles,calculated by TOUGH2, as state variables. This new model, CLMT2,preserves the best aspects of both submodels: the state of the artmodeling capability of surface energy and hydrologic processes from CLM3and the more realistic physical process based modeling capability ofsubsurface hydrologic processes from TOUGH2. The preliminary simulationresults show that the coupled model greatly improves the predictions ofthe water table, evapotranspiration, surface temperature, and moisture inthe top 20 cm of soil at a real watershed, as evaluated from 18 years ofobserved data. The new model is also ready to be coupled with anatmospheric simulation model, representing one of the first models thatare capable to simulate hydraulic processes from top of the atmosphere todeep ground.},
doi = {},
journal = {Vadose Zone Journal},
number = ,
volume = 7,
place = {United States},
year = {Thu Feb 08 00:00:00 EST 2007},
month = {Thu Feb 08 00:00:00 EST 2007}
}
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