Cooling effect and cooling accessibility of urban parks during hot summers in China's largest sustainability experiment

The rapid urbanization process has given rise to urban heating problem and social stratification, prompting calls to evaluate and improve the quality and equity of parks’ cooling service. Our study quantified cooling effect of 1,337 parks from both maximum and accumulation perspectives and investigated cooling accessibility through network analysis in 26 cities of Yangtze River Economic Belt (YREB), China's largest sustainability experiment. 1,189 (88.93%) parks showed significant cooling effect. On average, per park cooled down 2.34 ± 0.07 °C and 40.34 ± 1.17 ha, which was more than four times park area. The accumulative cooling intensity and gradient averaged at 108.55 ± 3.15 °C • m and 0.64 ± 0.02 °C, respectively. Our study also uncovered inequity in cooling accessibility in hot summers, as about 40.3% residents could not access to parks’ cooling service within 30-min walk. Suburban residents had more difficulty accessing to parks’ cooling services. This study can guide greater planning and design of parks to move toward a more equitable and livable direction across different urbanization hierarchy cities.