The urban cool island phenomenon in a high‐rise high‐density city and its mechanisms

Xinyan Yang; Yuan Li; Zhiwen Luo; Pak Wai Chan

doi:10.1002/joc.4747

journal article May 16, 2016

The urban cool island phenomenon in a high‐rise high‐density city and its mechanisms

Xinyan Yang

Yuan Li

Zhiwen Luo

Pak Wai Chan

International Journal of Climatology Vol. 37 No. 2 pp. 890-904 · Wiley

View at Publisher Save 10.1002/joc.4747

Abstract

ABSTRACTThe urban heat island (UHI) phenomenon has been studied extensively, but there are relatively fewer reports on the so‐called urban cool island (UCI) phenomenon. We reveal here that the UCI phenomenon exists in Hong Kong during the day and is associated with the UHI at night under all wind and cloud conditions. The possible mechanisms for the UCI phenomenon in such a high‐rise compact city have been discovered using a lumped urban air temperature model. A new concept of urban cool island degree hours (UCIdh) to measure the UCI intensity and duration is proposed. Our analyses reveal that when anthropogenic heat is small or absent, a high‐rise, and high‐density city experiences a significant daytime UCI effect. This is explained by an intensified heat storage capacity and the reduced solar radiation gain of urban surfaces. However, if anthropogenic heat in the urban area increases further, the UCI phenomenon still exists; yet, UCIdh decrease dramatically in a high‐rise compact city. In a low‐rise, low‐density city, the UCI phenomenon also occurs when there is no anthropogenic heat, but easily disappears when there is little anthropogenic heat, and the UHI phenomenon dominates. This probably explains why the UHI phenomenon is often observed, but the UCI phenomenon is rarely observed. The co‐existence of urban heat/cool island phenomena implies reduction of the daily temperature range in such cities, and its dependence on urban morphology also implies that urban morphology can be used to control the urban thermal environment.

Topics

No keywords indexed for this article. Browse by subject →

References

49

[1]

10.1017/s0022112003005019

[2]

10.1016/s1352-2310(03)00123-7

[3]

10.1002/qj.855

[4]

10.1175/1520-0493(1989)117<1872:pooiti>2.0.co;2

[5]

10.1175/jamc-d-12-083.1

[6]

10.1023/a:1016060103448

[7]

10.1256/qj.03.40

[8]

10.1007/s10546-004-1591-4

[9]

10.1029/jc083ic04p01889

[10]

Electrical and Mechanical Services Department:2012. Hong Kong Energy End‐Use Data 2012.http://www.emsd.gov.hk/emsd/eng/pee/edata.shtml(accessed May 2013).

[11]

10.1002/joc.1469

[12]

Gedzelman SD "Mesoscale aspects of the urban heat island around New York City" Theor. Appl. Climatol. (2003) 10.1007/s00704-002-0724-2

[13]

10.1175/1520-0450(1999)038<1262:apouad>2.0.co;2

[14]

10.1175/2010jamc2354.1

[15]

10.1175/1520-0450(1999)038<0448:uhimic>2.0.co;2

[16]

HangJ.2009. Wind Conditions and Urban Ventilation in Idealized City Models. PhD thesis The University of Hong Kong Hong Kong 365 pp.

[17]

10.1016/j.jweia.2011.07.004

[18]

10.1016/s1352-2310(99)00132-6

[19]

10.3828/tpr.73.2.1

[20]

10.1016/j.buildenv.2005.05.022

[21]

10.1175/jam2226.1

[22]

Landsberg HE (1981)

[23]

10.1007/s00704-005-0142-3

[24]

10.1016/j.atmosres.2009.07.006

[25]

10.1175/2008jamc1909.1

[26]

10.1002/1097-0088(200012)20:15<1931::aid-joc578>3.0.co;2-d

[27]

10.1016/j.landurbplan.2011.01.004

[28]

10.1002/qj.49710845502

[29]

Oke TR (1987)

[30]

OkeTR.2004. Initial guidance to obtain representative meteorological observations at urban sites. IOM Rep. 81 World Meteorological Organization: Geneva 47 pp.

[31]

10.1002/joc.2106

[32]

SailorDJ FanH.2004. The importance of including anthropogenic heating in mesoscale modeling of the urban heat island. 84th annual meeting of the AMS Symposium on Planning Nowcasting and Forecasting in the Urban Zone Seattle.

[33]

10.1016/j.atmosenv.2015.07.016

[34]

Santamouris M (2013)

[35]

10.1175/2008jamc1962.1

[36]

10.1007/s10661-012-2876-6

[37]

10.1016/s1352-2310(99)00158-2

[38]

10.1175/bams-d-11-00019.1

[39]

10.1007/978-94-009-3027-8

[40]

10.1023/b:boun.0000007230.96303.0d

[41]

10.1007/bf00122098

[42]

10.2307/1931815

[43]

10.1175/1520-0450(1981)020<1295:eotaot>2.0.co;2

[44]

10.1016/j.landurbplan.2011.05.003

[45]

10.1016/j.buildenv.2005.05.028

[46]

10.1016/s0017-9310(02)00379-4

[47]

10.1016/j.atmosenv.2009.02.062

[48]

10.1016/j.buildenv.2015.03.037

[49]

10.1016/j.apenergy.2007.11.002

Cited By

185

Green and blue infrastructure for urban cooling: Multi-scale mechanisms, spatial optimization, and methodological integration

Meng Yang, Peng Ye · 2025

Sustainable Cities and Society

Investigating the urban heat island effect: Impacts of diverse urban morphologies in semi-arid Marrakesh

Achraf Rachidi, Sanaa Hayani Mounir · 2025

Urban Climate

How do morphology factors affect urban heat island intensity? an approach of local climate zones in a fast-growing small city, Yangling, China

He Zhang, Chongqing Wang · 2024

Ecological Indicators

Characteristics of Urban Heat Island in China and Its Influences on Building Energy Consumption

Zihan Wang, Yicheng Zhang · 2022

Applied Sciences

Contribution of urban expansion to surface warming in high-altitude cities of the Tibetan Plateau

Yali Zhong, Shuqing Chen · 2022

Climatic Change

Experimental study of urban microclimate on scaled street canyons with various aspect ratios

Jian Hang, Guanwen Chen · 2022

Urban Climate

Towards sustainable urban transition: A critical review of strategies and policies of urban village renewal in Shenzhen, China

Wenjian Pan, Juan Du · 2021

Land Use Policy

Urban Heat Island intensity and buildings’ energy needs in Duran, Ecuador: Simulation studies and proposal of mitigation strategies

J. Litardo, M. Palme · 2020

Sustainable Cities and Society

U.K. Climate Projections: Summer Daytime and Nighttime Urban Heat Island Changes in England’s Major Cities

Y. T. Eunice Lo, Daniel M. Mitchell · 2020

Journal of Climate

Spatial Distribution of Land Surface Temperatures in Kuwait: Urban Heat and Cool Islands

Barrak Alahmad, Linda Powers Tomasso · 2020

International Journal of Environmen...

Scaled outdoor experimental studies of urban thermal environment in street canyon models with various aspect ratios and thermal storage

Guanwen Chen, Dongyang Wang · 2020

Science of The Total Environment

The influence of aspect ratios and solar heating on flow and ventilation in 2D street canyons by scaled outdoor experiments

Guanwen Chen, Xia Yang · 2020

Building and Environment

Urban heat island effect: A systematic review of spatio-temporal factors, data, methods, and mitigation measures

Kaveh Deilami, Md. Kamruzzaman · 2018

International Journal of Applied Ea...

Metrics

185

Citations

49

References

Details

Published: May 16, 2016
Vol/Issue: 37(2)
Pages: 890-904
License: View

Authors

X

Xinyan Yang

Department of Mechanical Engineering The University of Hong Kong China

Y

Yuan Li

Department of Mechanical Engineering The University of Hong Kong China

Z

Zhiwen Luo

School of the Built Environment The University of Reading UK

P

Pak Wai Chan

Hong Kong Observatory Kowloon China

Funding

Research Grants Council Collaborative Research Fund Scheme Award: HKU9/CRF/12G

Cite This Article

Xinyan Yang, Yuan Li, Zhiwen Luo, et al. (2016). The urban cool island phenomenon in a high‐rise high‐density city and its mechanisms. International Journal of Climatology, 37(2), 890-904. https://doi.org/10.1002/joc.4747

The urban cool island phenomenon in a high‐rise high‐density city and its mechanisms

You May Also Like