2026-04-13T01:25:21Zhttps://recercat.cat/oai/request

oai:recercat.cat:10256/76922024-06-14T09:36:29Zcom_2072_452955com_2072_2054col_2072_453063

00925njm 22002777a 4500 dc Salvador, Rosa author Calbó Angrill, Josep author Millán, Millan M. author 1999 The use of two-dimensional spectral analysis applied to terrain heights in order to determine characteristic terrain spatial scales and its subsequent use for the objective definition of an adequate grid size required to resolve terrain forcing are presented in this paper. In order to illustrate the influence of grid size, atmospheric flow in a complex terrain area of the Spanish east coast is simulated by the Regional Atmospheric Modeling System (RAMS) mesoscale numerical model using different horizontal grid resolutions. In this area, a grid size of 2 km is required to account for 95% of terrain variance. Comparison among results of the different simulations shows that, although the main wind behavior does not change dramatically, some small-scale features appear when using a resolution of 2 km or finer. Horizontal flow pattern differences are significant both in the nighttime, when terrain forcing is more relevant, and in the daytime, when thermal forcing is dominant. Vertical structures also are investigated, and results show that vertical advection is influenced highly by the horizontal grid size during the daytime period. The turbulent kinetic energy and potential temperature vertical cross sections show substantial differences in the structure of the planetary boundary layer for each model configuration http://hdl.handle.net/10256/7692 Meteorologia Meteorology Anàlisi espectral Spectrum analysis Horizontal Grid Size Selection and its Influence on Mesoscale Model Simulations