| Summary: | 碩士 === 東海大學 === 環境科學與工程學系 === 101 === In recent years, the rapid progress of civilization and urbanization has produced the serious air pollution. And the air pollution episodes are mainly caused by human factors such as vehicle exhausts and industrial pollution and accompany with certain weather pattern. The meteorological and air pollutants data from government-owned observation stations are used to analyze the correlation among wind field, urban heat island and pollutant concentration in central Taiwan during four periods (21-23 March, 22-24 May, 8-10 August and 2-4 October in 2012). This study has also discussed the influence of urban heat island episodes, diurnal variation and sea breeze to heat island phenomenon and pollutant concentration. In addition, in this study, the tethersonde was used to collect air samples of different height and analyze the vertical distribution of pollutants in heat island center.
The result indicates that Dali is the heat island center of central Taiwan. The phenomenon of convergence, which caused by urban heat island (UHI), is more obvious between afternoon and evening (1500LST~1800LST). There was a significant decrease in wind speed under the influence of phenomenon of convergence while making the anticlockwise direction and turn out to be concentrate toward heat island center. Furthermore, the weather pattern might concentrate and accumulate air pollutants to the heat island center and then cause serious air pollution episodes.
|
|---|
