Satellite-derived land surface parameters for mesoscale modelling of the Mexico City basin

[摘要] Mesoscale meteorological modelling is an important tool to help understandair pollution and heat island effects in urban areas. Accurate wind simulationsare difficult to obtain in areas of weak synoptic forcing. Local factors havea dominant role in the circulation and include land surface parameters andtheir interaction with the atmosphere.This paper examines an episode during the MCMA-2003 field campaign held inthe Mexico City Metropolitan Area (MCMA) in April of 2003.Because the episode has weak synoptic forcing, there is the potentialfor the surface heat budget to influence the local meteorology.High resolution satellite observations are used to specify the land use,vegetation fraction, albedo and surface temperaturein the MM5 model. Making use of these readily available data leads toimproved meteorological simulations in the MCMA, both for the windcirculation patterns and the urban heat island.Replacing values previously obtained from land-usetables with actual measurements removes the number of unknowns in the modeland increases the accuracy of the energy budget.In addition to improving the understanding of local meteorology, this sets thestage for the use of advanced urban modules.

[学科分类] 大气科学