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Affiliation: Code 614.3 Hydrological Sciences Branch
Event Date: Tuesday, July 26, 2005
Location: GSFC, Building 33, Room A128
Time: 12:00 - 1:00 PM
Bulk Surface Momentum Parameters for Satellite-Derived Vegetation Roughness Fields
The bulk of aerodynamic parameters associated with the absorption of surface momentum by vegetated landscapes are theoretically estimated within the context of Raupach's roughness sublayer formulation. The parameters include the bulk canopy drag coefficient, maximum u*/uh, sheltering coefficient, and canopy area density at the onset of over-sheltering. Parameters are estimated for several IGBP land cover classes: Evergreen needleleaf forests, broadleaf deciduous forest, grasslands, croplands, and open shrublands. The estimation approach applies the Method of Moments to published roughness data from several international field experiments and other journal sources. The results provide the necessary surface momentum parameters for satellite-based estimation of momentum aerodynamic roughness length, z0, and zero-plane displacement height, d0, required in most atmospheric circulation and hydrological simulation models used today. Examples of seasonal roughness fields using MODIS imagery are presented for the US Southern Great Plains.
Posted or updated: Tuesday, July 26, 2005
Editor: Paul Przyborski
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