Wu Hao, Zeng Qian, Chen Qianhu, Dewancker Bart
Hangzhou City Planning and Design Academy, Hangzhou, 310012, China; Department of Architecture, The University of Kitakyushu, Kitakyushu, 808-0135, Japan.
Department of Architecture, The University of Kitakyushu, Kitakyushu, 808-0135, Japan.
J Environ Manage. 2025 Jan;373:123548. doi: 10.1016/j.jenvman.2024.123548. Epub 2024 Dec 5.
The urban heat island (UHI), exacerbated by urbanization and warming, poses a threat to urban residents' health. While urban parks are key to UHI mitigation, their cooling effects and dynamics of newly constructed parks remain poorly understood. In this study, 20 new parks in Hangzhou were selected to investigate the characteristics of urban land surface temperatures (LST) alterations before-and-after park construction by using the single-window inversion on three years of Landsat 8 satellite imagery. Correlation analysis and Random Forest model were utilized to explore the influence of park attributes and surrounding landscapes on their cooling impact. The results indicate that newly constructed parks significantly reduce urban LST: by 0.31 °C inside the park and 0.64 °C in its surroundings, reaching 0.84 °C and 1.08 °C as parks mature. From 2022 to 2023, average park cooling distance (PCD) increased from 104.40 m to 147.50 m, park cooling area (PCA) expanded from 14.11ha to 17.88ha, park cooling intensity (PCI) rose from 0.64 °C to 1.08 °C, and park cooling efficiency (PCE) increased from 4.66 to 7.30. Correlation analysis and Random Forest model reveal that PCA is mainly affected by park area, while PCD, PCE, and PCI are mainly affected by landscape structure of surrounding building patches. These findings deepen understanding of park cooling dynamics, offering a clearer direction for maximizing park cooling benefits.
城市化和气候变暖加剧了城市热岛效应（UHI），对城市居民的健康构成威胁。虽然城市公园是缓解城市热岛效应的关键，但新建公园的降温效果及其动态变化仍鲜为人知。在本研究中，选取了杭州的20个新建公园，利用单窗反演算法，基于三年的Landsat 8卫星影像，研究公园建设前后城市地表温度（LST）变化的特征。利用相关分析和随机森林模型，探讨公园属性和周边景观对其降温效果的影响。结果表明，新建公园显著降低了城市地表温度：公园内部降低了0.31°C，周边降低了0.64°C；随着公园的成熟，降温幅度分别达到0.84°C和1.08°C。从2022年到2023年，平均公园降温距离（PCD）从104.40米增加到147.50米，公园降温面积（PCA）从14.11公顷扩大到17.88公顷，公园降温强度（PCI）从0.64°C上升到1.08°C，公园降温效率（PCE）从4.66提高到7.30。相关分析和随机森林模型表明，PCA主要受公园面积影响，而PCD、PCE和PCI主要受周边建筑斑块景观结构影响。这些发现加深了对公园降温动态的理解，为最大化公园降温效益提供了更清晰的方向。
