Application of Two-Dimensional Terrain Height Spectra to Mesoscale Modeling

摘要: Abstract A caution is offered with regard to the use of one-dimensional terrain spectra indicate grid resolution needed resolve forcing in mesoscale numerical modeling exercises. To illustrate this, two-dimensional height are presented for two contrasting terrains: a relatively direction free topography (a portion southcentral British Columbia, Canada) and highly ordered ridge valley Pennsylvania). Isoamplitude plots show clearly morphological differences between regions degree directionality terrain. An investigation wavenumber dependence shows spectral roll-off first case be essentially independent decay roughly as -5/2 power over range 0.04 8.33 km−1. By contrast, second strongly dependent on an ex...