HR: 14:55h
AN: H33K-06    [Abstracts]
TI: What can Maximum Entropy Production Tell us About General Trends in Land Surface Hydrology and its Predictability?
AU: * Kleidon, A
EM: akleidon@bgc-jena.mpg.de
AF: Max Planck Institute for Biogeochemistry, Hans-Knoell-Str. 10, Jena, MD 07743, Germany
AU: Stieglitz, M
EM: marc.stieglitz@ce.gatech.edu
AF: Georgia Institute of Technology, 790 Atlantic Drive, Atlanta, GA 30332, United States
AU: Schymanski, S
EM: sschym@bgc-jena.mpg.de
AF: Max Planck Institute for Biogeochemistry, Hans-Knoell-Str. 10, Jena, MD 07743, Germany
AB: The proposed principle of Maximum Entropy Production (MEP) states that complex systems organize into steady states that maximize rates of entropy production. Even though the role of thermodynamics in land surface hydrology is not widely recognized, it plays a key role in driving the hydrologic cycle to a state far from thermodynamic equilibrium, as indicated by unsaturated conditions in the atmosphere. In order to investigate the applicability of MEP to the hydrologic cycle, we provide first order estimates of entropy production associated with precipitation, soil wetting, soil moisture redistribution, evapotranspiration, and runoff. We find that the largest contribution comes from evapotranspiration. We then discuss the role that vegetation plays in this budget. It would seem that vegetation acts to enhance and possibly maximize entropy production associated with land surface water exchange. This would have important implications for the response of hydrological fluxes at the land surface to climate variability that could be tested with empirical observations.
DE: 1833 Hydroclimatology
DE: 1836 Hydrological cycles and budgets (1218, 1655)
DE: 1843 Land/atmosphere interactions (1218, 1631, 3322)
DE: 1866 Soil moisture
SC: Hydrology [H]
MN: 2007 Fall Meeting