HR: 16:20h
AN: H24D-02 INVITED    [Abstracts]
TI: Coupled groundwater-atmosphere modeling: effects on atmospheric boundary layer development
AU: * Chow, F K
EM: chow@ce.berkeley.edu
AF: University of California, Berkeley, Civil and Environmental Engineering, Berkeley, CA 94720-1710, United States
AU: Maxwell, R M
EM: maxwell5@llnl.gov
AF: Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550, United States
AU: Kollet, S J
EM: stefan.kollet@uni-bonn.de
AF: Bonn University, Meteorological Institute Auf dem Huegel 20, Bonn, 53121, Germany
AU: Daniels, M H
EM: mdaniels@ce.berkeley.edu
AF: University of California, Berkeley, Civil and Environmental Engineering, Berkeley, CA 94720-1710, United States
AU: Rihani, J F
EM: rjehan@berkeley.edu
AF: University of California, Berkeley, Civil and Environmental Engineering, Berkeley, CA 94720-1710, United States
AB: Newly-developed coupled land-atmosphere models which incorporate both subsurface and atmospheric moisture dynamics have the potential to change our understanding of the hydrologic cycle. This presentation describes the effects of coupled groundwater-atmosphere modeling on simulations of the atmospheric boundary layer. Both field observations and simulations indicate strong sensitivity of atmospheric dynamics to land-surface conditions, in particular surface soil moisture. Simulations of atmospheric flow in Owens Valley (California) and in the Riviera Valley (Switzerland) show strong sensitivity to land-surface conditions, thus motivating the need for more accurate representations of soil moisture. In addition to influences from weather and seasonal changes, soil moisture dynamics respond to diurnal heat fluxes on the land surface. Using our new fully-coupled groundwater-atmosphere model, we have demonstrated correlations of soil moisture and land-surface heat fluxes with groundwater fluctuations on short, diurnal time scales. By explicitly calculating groundwater dynamics for our domain of interest, we are able to produce realistic time- and space-varying soil moisture distributions that naturally correspond to variations in topography and surface evaporation. Simulations in idealized and real watersheds are shown to illustrate these effects. The observed variations in surface moisture distribution have large impacts on the moisture and temperature structure in the atmosphere, leading to changes in boundary layer depth and convective motions as compared to standard soil moisture representations. Our coupled model framework will allow detailed investigation of the complex cycle of land-atmosphere processes affecting moisture distributions in the subsurface and the atmosphere.
DE: 1830 Groundwater/surface water interaction
DE: 1843 Land/atmosphere interactions (1218, 1631, 3322)
DE: 3307 Boundary layer processes
DE: 3322 Land/atmosphere interactions (1218, 1631, 1843)
DE: 3329 Mesoscale meteorology
SC: Hydrology [H]
MN: 2007 Fall Meeting