The Influence of Synoptic Pattern and Atmospheric Boundary Layer on PM_(10) and Urban Heat Island

摘要

The purpose of this study is to evaluate the influence of synoptic pattern, as well as other corresponding boundary layer dynamic characteristics, on PM_(10) concentrations and urban heat island. Statistical analyses of PM_(10) concentrations (aerosol particle diameter less than 10 urn) were conducted and daily maximum urban heat island intensity was investigated during December 2008. Synoptic patterns were analysed through an interactive desktop synoptic classification application tool. Atmospheric boundary layer dynamical characteristics were modelled using mesoscale model 5. Results showed significant correlation of synoptic patterns and the corresponding urban boundary layer dynamic characteristics with PM_(10) concentrations and urban heat island intensities. The PM_(10) concentrations and urban heat island intensities were associated with anticyclone and low-pressure trough pattern under stable atmos- pheric boundary layer. High wind speed, high mixing layer height and weak inversion depth would cause a reduction of PM_(10) concentration and urban heat island intensity. However, the effect of meteorological factors on PM_(10) and urban heat island was not completely synchronous, the peak and trough of PM_(10) concentration appeared a little later than the occurrence of urban heat island. There is a need for city planners to develop strategies to relieve the unhealthy effects of urban heat island and PM pollution. This paper has outlined strategies to alleviate urban heat island and pollution for a more pleasant urban environment.