Evaluating the Impact of the Morphological Transformation of Urban Sites on the Urban Thermal Microenvironment

Salman Ali,Baofeng Li

doi:10.3390/buildings8120182

Abstract

Tropical cities currently face issues of climate change resulting from rapid urbanization and the impact of urban morphological transformations on the microclimate. The analysis of urban physical forms and patterns is a realisticmethodfor quantifying these impacts. This work examined the impact of morphological transformations of an urban site in Wuhan, China, on the microthermal environment at different time periods. We also quantified and compared the impact of four urban site morphologies on ambient air temperature. The morphological changes of the study site were inferred from Google Earth images acquired at different time points in 2006 and 2013. ENVI-met simulation software was used to compare the changes in temperature at the selected site by specific date. The year- and time-based analysis of existing urban morphologies and their impact on the microurban thermal environment shows that the overall minimum and maximum values of morning and afternoon ambient air temperature are nearly the same for the 2013 and 2006 morphologies. The maximum temperature difference was observed in the afternoon (14:00), with an average difference of approximately 2 °C in the east. The findings of this research could provide a useful guide for optimizing the transformation of urban site planning and design and a suitable method for assessing the impact of built-up areas on the environment.

Highlights

The present study aims to investigate the microclimatic impacts of the morphological transformation of urban areas
Compared with the 2006 morphology, the 2013 morphology had a greater influence on Tair values at specific sites but not on the overall minimum and maximum values because of the additional building blocks at specific locations
The results of this study show that quantitative measurement of the urban microclimate is a valid method for understanding the microclimatic effects of urbanization

Summary

Introduction

The greater part of the global population currently live in urban regions; currently, 75% of the world’s population live in industrialized nations [1]. Century has negatively affected microclimatic conditions and increased air temperature in urban areas [2]. Progressive changes in urban morphological characteristics, the replacement of natural surfaces with rough materials such as concrete and asphalt, have resulted in the storage and re-emittance of solar radiation in urban spaces. Air temperatures in urban microenvironments have increased [3,4]. The microclimates of cities and urban areas in developing countries are greatly affected by constant urbanization [5]. The rate of urban expansion in tropical developing countries is constantly increasing, with an average expected increment of 1 million people per year [6]

Methods

Findings

Discussion

Conclusion