A Study of Local Climate Zones in Abu Dhabi with Urban Weather Stations and Numerical Simulations

Abstract

In many cities that have experienced rapid growth like Abu Dhabi, urban microclimate scenarios evolve rapidly as well and it is important to study the urban thermal dynamics continuously. The Local Climate Zone (LCZ) classification considers factors related to the physical properties like surface cover and surface structure of the city which allow to analyze urban heat flows. Abu Dhabi city is rapidly expanding and is characterized by highly heterogeneous types of built forms that comprise mainly of old mid-rise and modern high-rise buildings with varied degrees of vegetation cover in different parts of the city. The fact that it is a coastal city in a desert environment makes it quite unique. This paper presents an approach of studying urban heat flows in such heterogeneous setup. First, the city is classified into local climate zones using images acquired by Landsat Satellite. Numerical simulations are performed in the designated LCZs using a computational fluid dynamics software, Envi-met. The results of Envi-met are calibrated and validated using in-situ measurements across all four seasons. The calibrated models are then applied to study entire Abu Dhabi island across different seasons. The results indicate a clear presence of urban heat island (UHI) effect when averaged over the full day which is varying in different zones. The zones with high vegetation do not show large average UHI effect whereas the effect is significant in densely built zones. The study also validates previous observations on the inversion of UHI effect during the day and in terms of diurnal response.

Remote Sensing Image-Based Analysis of the Urban Heat Island Effect in Bragança, Portugal

“…Considering the methodological application in other locations [36][37][38], Bragança (Portugal) was chosen as the study area for this work because it has the following characteristics: (i) there are no previous studies using RS data to analyze the LST at the site; (ii) it has the previous classification of Bragança in Local Climate Zones (LCZ) and UHI studies considering data from air temperature measured by the sensor network (Ta SN ) [23,32,39], that can be used to validate the data obtained in RS; (iii) its mountainous configuration can influence the circulation and speed of winds corroborating, naturally, to the formation of the UHI; (iv) presence of centralized urban densification with surrounding rural areas.…”

Analysis of the urban heat island in Bragança, Portugal, using MODIS data (2003-2022)

“…This city has heterogeneous surfaces, including building forms, and because it is in a coastal region in a desert environment, there are specificities in heat exchange. The study evaluated the UHI and seasonality in different seasons and times of the day and identified that the average temperature values, calculated throughout the day, pointed out the presence of UHI in different zones, especially in the densely urbanized ones 38 . Other studies associate LCZ classifications as a tool to assess the influence of LST distribution and UHI/SUHI effect on specific surfaces and have identified that the temperature was higher in densely urbanized areas [39][40][41][42][43] .…”

Characterization of Local Climate Zones Using ENVI-met and Site Data in the City of Al-Ain, UAE

“…The zones are differentiated based on surface cover, material, structure and human activity. The LCZ classification can be used as an input for urban micro-climate models [5].…”

“…Recent studies have used the World Urban Database and Portal Tool (WUDAPT) platform for analysing climate zones in cities like Xi'an, China; Katuna, Nigeria; the London metropolitan area, UK etc. [5][6][7]. The interaction of these zones are linked to studying various topics, such as pollution, city expansion, UHI etc.…”