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The surface roughness length, in meters, is a measure of the near-surface wind resistance. For informational purposes, Table D - 1 ( Surface Roughness Lengths (m) for Various Land Uses ) provides typical surface roughness lengths for a variety of land uses. As shown, typical values range from 0.0001 meters over water to 1.00 meters within an urban environment. A typical airport environment has a surface roughness length of 0.10 meters. 

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The albedo is the fraction of total incident solar radiation reflected by the surface back to space without absorption. Typical values range from 0.10 for thick deciduous forests to 0.90 for fresh snow. Table D - 2 ( Albedo for Various Land Uses ) provides typical albedo for a variety of land uses. A typical airport environment has an albedo of 0.20. 

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important concept in urban meteorology as the building of tall structures, such as skyscrapers, has an effect on roughness length and wind patterns 

82 The Bowen ratio is used to describe the type of heat transfer in a water body. The Bowen ratio is the mathematical method generally used to calculate heat lost (or gained) in a substance; it is the ratio of energy fluxes from one state to another by sensible and latent heating respectively. 83 

The ratio of reflected radiation from the surface to incident radiation upon it or reflecting power of a surface. 

