TY - JOUR

T1 - Critical review on the cooling effect of urban blue-green space

T2 - A threshold-size perspective

AU - Yu, Zhaowu

AU - Yang, Gaoyuan

AU - Zuo, Shudi

AU - Jørgensen, Gertrud

AU - Koga, Motoya

AU - Vejre, Henrik

PY - 2020

Y1 - 2020

N2 - The cooling effect of blue-green space has been recognized as a promising approach to mitigating the urban heat island (UHI), while the quantitative role (threshold-size for cooling) is still uncertain. This paper aims to present the latest progress and controversies on the studies of the cooling effects of waterbodies, greenspaces, and parks. In order to do this research, international search engines have been employed to systematically search peer-reviewed articles, including the cooling effect of blue-green space and threshold-size-based UHI mitigation studies. After that, the inductive analysis is used to analyze the relevant literature. We found that previous studies concentrated on the correlations between different landscape types, temperature variations and the quantification of cooling intensity, etc. However, threshold-size-based research has received less attention, which limits the ability to make specific recommendations for actionable planning and management – use the smallest blue-green space for the best cooling effect. The review also revealed the controversies over the effects of blue-green space size, shape, landscape composition and configuration on cooling effect. Besides, we pointed out that the uncertainties (i.e., the optimal proportion of blue-green space in a park) and the reasons of controversial results of the cooling effect need to be further investigated. We also suggested that more attention should be paid to quantify the contributions of local background climate and landscape characteristics to the cooling effect (threshold-size) of blue-green space. This review would give us a deeper understanding of the field and provide insights into actionable climate adaption planning.

AB - The cooling effect of blue-green space has been recognized as a promising approach to mitigating the urban heat island (UHI), while the quantitative role (threshold-size for cooling) is still uncertain. This paper aims to present the latest progress and controversies on the studies of the cooling effects of waterbodies, greenspaces, and parks. In order to do this research, international search engines have been employed to systematically search peer-reviewed articles, including the cooling effect of blue-green space and threshold-size-based UHI mitigation studies. After that, the inductive analysis is used to analyze the relevant literature. We found that previous studies concentrated on the correlations between different landscape types, temperature variations and the quantification of cooling intensity, etc. However, threshold-size-based research has received less attention, which limits the ability to make specific recommendations for actionable planning and management – use the smallest blue-green space for the best cooling effect. The review also revealed the controversies over the effects of blue-green space size, shape, landscape composition and configuration on cooling effect. Besides, we pointed out that the uncertainties (i.e., the optimal proportion of blue-green space in a park) and the reasons of controversial results of the cooling effect need to be further investigated. We also suggested that more attention should be paid to quantify the contributions of local background climate and landscape characteristics to the cooling effect (threshold-size) of blue-green space. This review would give us a deeper understanding of the field and provide insights into actionable climate adaption planning.

U2 - 10.1016/j.ufug.2020.126630

DO - 10.1016/j.ufug.2020.126630

M3 - Journal article

JO - Urban Forestry & Urban Greening

JF - Urban Forestry & Urban Greening

SN - 1618-8667

M1 - 126630

ER -