City size promotes to park cooling services and equity

Abstract

The contribution of urban parks to enhancing thermal comfort and improving urban resilience is well-established. However, the mechanisms influencing their disproportionate cooling capacity across cities remain unclear. Therefore, understanding the factors that affect park cooling service (PCS) and its spatial equity is crucial for developing targeted urban climate risk mitigation strategies. This study evaluated the PCS and its spatial equity across 240 urban parks in 12 cities of the Yangtze River Delta, analyzing patterns along the urbanization gradient. The findings reveal that: (1) PCS is positively correlated with urbanization level, with the average park cooling service capacity (PCSC) in mega cities reaching 140 % of that in small cities (0.17 vs. 0.12). (2) spatial equity of PCSC also increases with urbanization, with mega cities exhibiting a 51 % improvement compared to small cities (0.47 vs. 0.95). (3) observed inequalities are mainly driven by industrial structure and urban–rural disparity, where relative temperature difference exerts the strongest positive effect on equity (0.23–18.00), while the share of the tertiary industry shows the strongest negative effect (−0.34 to −2.35). (4) smaller cities contain more parks with low cooling service levels (52 %) and have lower cooling area thresholds (0.56 km²), suggesting that PCS enhancement in smaller cities is more feasible. These findings provide valuable guidance for urban park planning and design to promote equity and livability across cities at different stages of urbanization.