Numerical Study of the Effects of Topography and Urbanization on the Local Atmospheric Circulations over the Beijing-Tianjin-Hebei, China

Yucong Miao,Shu Wang,Shuhua Liu,Yijia Zheng,Bicheng Chen

doi:10.1155/2015/397070

Yucong Miao, Shu Wang + Show 3 more

Open Access

https://doi.org/10.1155/2015/397070

Copy DOI

Abstract

The effects of the topography and urbanization on the local atmospheric circulations over the Beijing-Tianjin-Hebei (BTH) region were studied by the weather research and forecasting (WRF) model, as well as the interactions among these local atmospheric circulations. It was found that, in the summer day time, the multiscale thermally induced local atmospheric circulations may exist and interact in the same time over the BTH region; the topography played a role in the strengthening of the sea breeze circulations; after sunset, the inland progress of sea breeze was slowed down by the opposite mountain breeze; when the land breeze circulation dominated the Bohai bay, the mountain breeze circulation can couple with the land breeze circulation to form a large circulation ranging from the coastline to the mountains. And the presence of cities cannot change the general state of the sea-land breeze (SLB) circulation and mountain-valley breeze (MVB) circulation but acted to modify these local circulations slightly. Meanwhile, the development of the urban heat island (UHI) circulation was also strongly influenced by the nearby SLB circulation and MVB circulation.

Highlights

The Beijing-Tianjin-Hebei region (BTH), located in North China Plain, is one of China’s most economically developed regions, with a region of 216,000 square km in size and over 100 million in population
Facing the Bohai Sea, the BTH region is frequently under the influence of sea-land breeze (SLB) circulations during summertime; besides, the BTH region is located in a mountainous area, which is affected by the mountain-valley breeze (MVB) circulation
The effects of the topography and urbanization on the local thermally induced circulations over the TBH region were investigated by weather research and forecasting (WRF)

Summary

Introduction

The Beijing-Tianjin-Hebei region (BTH), located in North China Plain, is one of China’s most economically developed regions, with a region of 216,000 square km in size and over 100 million in population. The study of Lo et al showed that urbanization enhanced the pollutant trapping and contributes to the overall poor air quality in the Pearl River Delta [11]. These local atmospheric circulations can couple and interact [12]. Lo et al set up a number of numerical experiments by numerical model to investigate the impacts of urbanization and its associated UHI on the local- and regional-scale atmospheric circulations over the Pearl River Delta, and it was found that stronger UHI in the Pearl River Delta enhances the mesoscale sea-breeze circulation [13]. The effects of the topography and urbanization on the local atmospheric circulations over the BTH region were investigated by using the idealized initial and boundary conditions.

Models Description and Numerical Setup

Results and Discussions

Conclusions