How can urban green spaces be planned for climate adaptation in subtropical cities?

TY - JOUR

T1 - How can urban green spaces be planned for climate adaptation in subtropical cities?

AU - Yu, Zhaowu

AU - Guo, Xieying

AU - Jørgensen, Gertrud

AU - Vejre, Henrik

PY - 2017

Y1 - 2017

N2 - The cooling effect of greenspaces is an important ecosystem service, essential for mitigating the urban heat island (UHI) effect and thus increasing urban resilience to climate change. Techniques based on landscape planning to alleviate the increasing frequency of extreme climate are becoming more of a focus in urban ecology studies. In this paper, we proposed and defined the urban cooling island (UCI) extent, intensity, and efficiency, as well as the threshold value of efficiency (TVoE) introduced from the “law of diminishing marginal utility” for the first time. The radiative transfer equation has been compared with other algorithms and used to retrieve accurate land surface temperature (LST) in a subtropical city of China − Fuzhou. Two important and arguable factor − size and shape of greenspaces also been expressed and explored. The results indicate that: (1) larger-sized greenspaces produce a higher cooling effect. However, there exist a TVoE, which is in line with our hypothesis. The TVoE in Fuzhou is 4.55 ha. (2) The circles and squares greenspaces have a significant correlation with LST and also show the highest UCI intensity and efficiency. (3) 92% of the maximum extent of greenspaces are within the 30–180 m limit, and the mean UCI extent and intensity are 104 m and 1.78 °C. (4) The greenspaces connected with waterbodies intensified the UCI effects, whereas the grassland-based greenspace shows the weakest UCI effects. The methodology and results of this study could help urban planners to mitigate the UHI effects efficiently, and to employ the climate adaptive planning.

AB - The cooling effect of greenspaces is an important ecosystem service, essential for mitigating the urban heat island (UHI) effect and thus increasing urban resilience to climate change. Techniques based on landscape planning to alleviate the increasing frequency of extreme climate are becoming more of a focus in urban ecology studies. In this paper, we proposed and defined the urban cooling island (UCI) extent, intensity, and efficiency, as well as the threshold value of efficiency (TVoE) introduced from the “law of diminishing marginal utility” for the first time. The radiative transfer equation has been compared with other algorithms and used to retrieve accurate land surface temperature (LST) in a subtropical city of China − Fuzhou. Two important and arguable factor − size and shape of greenspaces also been expressed and explored. The results indicate that: (1) larger-sized greenspaces produce a higher cooling effect. However, there exist a TVoE, which is in line with our hypothesis. The TVoE in Fuzhou is 4.55 ha. (2) The circles and squares greenspaces have a significant correlation with LST and also show the highest UCI intensity and efficiency. (3) 92% of the maximum extent of greenspaces are within the 30–180 m limit, and the mean UCI extent and intensity are 104 m and 1.78 °C. (4) The greenspaces connected with waterbodies intensified the UCI effects, whereas the grassland-based greenspace shows the weakest UCI effects. The methodology and results of this study could help urban planners to mitigate the UHI effects efficiently, and to employ the climate adaptive planning.

KW - Climate adaptation

KW - Threshold value of efficiency

KW - Urban cooling island

KW - Urban greenspace

KW - Urban planning

U2 - 10.1016/j.ecolind.2017.07.002

DO - 10.1016/j.ecolind.2017.07.002

M3 - Journal article

AN - SCOPUS:85021726276

SN - 1470-160X

VL - 82

SP - 152

EP - 162

JO - Ecological Indicators

JF - Ecological Indicators

ER -