Diverse cooling effects of green space on urban heat island in tropical megacities

• DOI: 10.3389/fenvs.2022.1073914
• Publication Date: 2022-11-24T07:51:40Z
• Authors: Chunbo Li; Linlin Lu; Zongtang Fu; Ranhao Sun; Luyang Pan; Liying Han; Huadong Guo; Qingting Li
• Keywords: Urban Heat Island; Megacity; Intensity; Tropical climate

Cities in tropical regions are experiencing high heat risks by overlaying the urban island (UHI) effect. Urban green space (UGS) can provide local cooling effect and reduce UHI. However, there still lack a comprehensive exploration of characteristics UHI UGS due to cloud coverage limited number available remote sensing observations. In this study, enhanced spatial temporal adaptive reflectance data fusion method was employed develop an land surface temperature winter seasons three megacities, Dhaka, Kolkata, Bangkok. The spatiotemporal variations (SUHI) were explored from 2000 2020 with 5-years interval. optimal size associated its effects assessed using threshold value efficiency (TVoE). relationship between intensity range (UCI) four landscape metrics patches, total area (P_Area), shape index (P_SI), normalized difference vegetation (P_NDVI), (P_LST), analyzed. results show that average SUHI increased 0.98°C, 1.42°C, 0.73°C Bangkok, respectively, 2020. maximum UCI ranges 4.83°C Bangkok 8.07°C varies 300 m 420 Kolkata. is 0.37 ha, 0.77 0.42 ha respectively. P_NDVI P_Area had significant positive on range, while background negative effects. With higher temperature, patch larger. This study provides useful information for developing effective mitigation adaptation strategies enhance climate resilience cities.