HR: 1330h
AN: H42A-1059    [PDF]
TI: A Simple Model to Determine the Effects of Surface Inhomogeneity in the Inner Region
AU: * Nichols, J J
EM: jennifer-nichols@uiowa.edu
AF: IIHR - Hydroscience \& Engineering, University of Iowa, 100 Stanley Hydraulics Laboratory, Iowa City, IA 52242 United States
AU: Eichinger, W E
EM: william-eichinger@uiowa.edu
AF: IIHR - Hydroscience \& Engineering, University of Iowa, 100 Stanley Hydraulics Laboratory, Iowa City, IA 52242 United States
AB: Remote sensing has potential to provide measurements of water vapor content over larger areas with fairly high spatial and temporal resolution. Over a horizontally homogeneous area, these measurements can be used to calculate evaporation for the entire region measured. However, there are problems in areas of heterogeneity: because of wind and turbulent mixing in the atmosphere, water vapor concentration gradients at one location may not be a good estimate of evaporation at that exact surface location. A model has been developed to predict the effects of single and multiple surface emission step changes on water vapor concentrations profiles. Using this model, correction factors are suggested for the determination of evaporative fluxes using the Monin-Obukhov similarity method. These correction factors adjust the concentration profiles for an upwind step change in emission rates given a neutral atmosphere. The addition of a correction factor for various atmospheric stabilities will be presented which will move further towards estimating evaporation over a heterogeneous surface.
DE: 1818 Evapotranspiration
SC: Hydrology [H]
MN: 2003 Fall Meeting