Effects of Evapotranspiration on Mitigation of Urban Temperature by Vegetation and Urban Agriculture

The temperature difference between an urban space and surrounding non-urban space is called the urban heat island effect (UHI). Global terrestrial evapotranspiration (ET) can consume 1.4803×1023 joules (J) of energy annually, which is about 21.74% of the total available solar energy at the top of at...

Full description

Bibliographic Details
Main Authors: Guo-yu QIU, Hong-yong LI, Qing-tao ZHANG, Wan CHEN, Xiao-jian LIANG, Xiang-ze LI
Format: Article
Language:English
Published: Elsevier 2013-08-01
Series:Journal of Integrative Agriculture
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2095311913605432
_version_ 1819069787724054528
author Guo-yu QIU
Hong-yong LI
Qing-tao ZHANG
Wan CHEN
Xiao-jian LIANG
Xiang-ze LI
author_facet Guo-yu QIU
Hong-yong LI
Qing-tao ZHANG
Wan CHEN
Xiao-jian LIANG
Xiang-ze LI
author_sort Guo-yu QIU
collection DOAJ
description The temperature difference between an urban space and surrounding non-urban space is called the urban heat island effect (UHI). Global terrestrial evapotranspiration (ET) can consume 1.4803×1023 joules (J) of energy annually, which is about 21.74% of the total available solar energy at the top of atmosphere, whereas annual human energy use is 4.935×1020 J, about 0.33% of annual ET energy consumption. Vegetation ET has great potential to reduce urban and global temperatures. Our literature review suggests that vegetation and urban agricultural ET can reduce urban temperatures by 0.5 to 4.0°C. Green roofs (including urban agriculture) and water bodies have also been shown to be effective ways of reducing urban temperatures. The cooling effects on the ambient temperature and the roof surface temperature can be 0.24-4.0°C and 0.8-60.0°C, respectively. The temperature of a water body (including urban aquaculture) can be lower than the temperature of the surrounding built environment by between 2 and 6°C, and a water body with a 16 m2 surface area can cool up to 2 826 m3 of nearby space by 1°C. Based on these findings, it can be concluded that the increase of evapotranspiration in cities, derived from vegetation, urban agriculture, and water body, can effectively mitigate the effect of urban heat islands.
first_indexed 2024-12-21T16:55:36Z
format Article
id doaj.art-056eaee4974a48a29f0bcdb5754db37e
institution Directory Open Access Journal
issn 2095-3119
language English
last_indexed 2024-12-21T16:55:36Z
publishDate 2013-08-01
publisher Elsevier
record_format Article
series Journal of Integrative Agriculture
spelling doaj.art-056eaee4974a48a29f0bcdb5754db37e2022-12-21T18:56:45ZengElsevierJournal of Integrative Agriculture2095-31192013-08-0112813071315Effects of Evapotranspiration on Mitigation of Urban Temperature by Vegetation and Urban AgricultureGuo-yu QIU0Hong-yong LI1Qing-tao ZHANG2Wan CHEN3Xiao-jian LIANG4Xiang-ze LI5Correspondence QIU Guo-yu, Tel: +86-755-26033309; Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Shenzhen Graduate School, Peking University, Shenzhen 518055, P.R.ChinaKey Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Shenzhen Graduate School, Peking University, Shenzhen 518055, P.R.ChinaKey Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Shenzhen Graduate School, Peking University, Shenzhen 518055, P.R.ChinaKey Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Shenzhen Graduate School, Peking University, Shenzhen 518055, P.R.ChinaKey Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Shenzhen Graduate School, Peking University, Shenzhen 518055, P.R.ChinaKey Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Shenzhen Graduate School, Peking University, Shenzhen 518055, P.R.ChinaThe temperature difference between an urban space and surrounding non-urban space is called the urban heat island effect (UHI). Global terrestrial evapotranspiration (ET) can consume 1.4803×1023 joules (J) of energy annually, which is about 21.74% of the total available solar energy at the top of atmosphere, whereas annual human energy use is 4.935×1020 J, about 0.33% of annual ET energy consumption. Vegetation ET has great potential to reduce urban and global temperatures. Our literature review suggests that vegetation and urban agricultural ET can reduce urban temperatures by 0.5 to 4.0°C. Green roofs (including urban agriculture) and water bodies have also been shown to be effective ways of reducing urban temperatures. The cooling effects on the ambient temperature and the roof surface temperature can be 0.24-4.0°C and 0.8-60.0°C, respectively. The temperature of a water body (including urban aquaculture) can be lower than the temperature of the surrounding built environment by between 2 and 6°C, and a water body with a 16 m2 surface area can cool up to 2 826 m3 of nearby space by 1°C. Based on these findings, it can be concluded that the increase of evapotranspiration in cities, derived from vegetation, urban agriculture, and water body, can effectively mitigate the effect of urban heat islands.http://www.sciencedirect.com/science/article/pii/S2095311913605432evapotranspirationurban heat islandvegetationtemperature
spellingShingle Guo-yu QIU
Hong-yong LI
Qing-tao ZHANG
Wan CHEN
Xiao-jian LIANG
Xiang-ze LI
Effects of Evapotranspiration on Mitigation of Urban Temperature by Vegetation and Urban Agriculture
Journal of Integrative Agriculture
evapotranspiration
urban heat island
vegetation
temperature
title Effects of Evapotranspiration on Mitigation of Urban Temperature by Vegetation and Urban Agriculture
title_full Effects of Evapotranspiration on Mitigation of Urban Temperature by Vegetation and Urban Agriculture
title_fullStr Effects of Evapotranspiration on Mitigation of Urban Temperature by Vegetation and Urban Agriculture
title_full_unstemmed Effects of Evapotranspiration on Mitigation of Urban Temperature by Vegetation and Urban Agriculture
title_short Effects of Evapotranspiration on Mitigation of Urban Temperature by Vegetation and Urban Agriculture
title_sort effects of evapotranspiration on mitigation of urban temperature by vegetation and urban agriculture
topic evapotranspiration
urban heat island
vegetation
temperature
url http://www.sciencedirect.com/science/article/pii/S2095311913605432
work_keys_str_mv AT guoyuqiu effectsofevapotranspirationonmitigationofurbantemperaturebyvegetationandurbanagriculture
AT hongyongli effectsofevapotranspirationonmitigationofurbantemperaturebyvegetationandurbanagriculture
AT qingtaozhang effectsofevapotranspirationonmitigationofurbantemperaturebyvegetationandurbanagriculture
AT wanchen effectsofevapotranspirationonmitigationofurbantemperaturebyvegetationandurbanagriculture
AT xiaojianliang effectsofevapotranspirationonmitigationofurbantemperaturebyvegetationandurbanagriculture
AT xiangzeli effectsofevapotranspirationonmitigationofurbantemperaturebyvegetationandurbanagriculture