Impact of urbanization on regional atmospheric boundary layer

Abstract

This study investigates the evolution of climatological impacts due to urbanization in Pearl River Delta (PRD) region, China during summer season. Land use data representing 1990s, 2000s and 2010s are obtained by classifying the land use from satellite images with machine learning techniques. This classification standards follows the guideline of land use classification from World Urban Database and Access Portal Tools (WUDAPT). Prior to the model simulation, remapping of WUDAPT land use categorization to USGS land use classification was done. Weather Research and Forecast model (WRF) was applied afterwards under the same initial and boundary conditions with respect to different land use data. Spatial comparison and statistical analysis showed a general increase in temperature and heat index, and also deceleration of wind speed due to urbanization. The increase in temperature would interrupt the occurance and patterns of wind-circulation, such as land-sea breeze and rural-urban breeze. Moreover, simulation shows that the sensible heat flux is increased in urbanized area due to stronger absorption in downwards longwave radiation, while the latent heat flux decreased due to less vegetation and existence of impervious surface.

Date of Award	2017
Original language	English
Awarding Institution	The Hong Kong University of Science and Technology