The ideal characteristics of landscape pattern and morphological spatial pattern for seasonal cool island regulation in urban park green space

Urban parks provide cool island through landscape pattern and morphological spatial pattern to regulate urban thermal environment. While previous studies have established the influence of urban park green space (UPGS) cooling in summer, there remains a lack of clarity regarding the single and synergistic effects of landscape pattern and morphological spatial pattern on seasonal park cool island. Therefore, we quantified the seasonal contributions of cool island in urban parks in Harbin, China. Spearman correlation analysis and Random Forest model were used to identify key factors influencing park cool island intensity (PCII) from landscape metrics and morphological metrics. Moreover, Geographical detector was employed to interpret the synergistic effects (nonlinear enhancement, bilinear enhancement) of them on seasonal PCII. The results indicated that: (1) UPGS have a cooling contribution in all four seasons, with the highest in summer and the lowest in winter. (2) Landscape and morphological metrics independently influence PCII, where optimizing metrics such as LPI, PLAND, and Core can enhance summer cooling while reducing winter cooling effects. (3) Synergistically, the interaction between landscape and morphology provides a more comprehensive explanation of PCII, where optimizing PD and Edge can amplify summer cooling without adverse winter impacts. To maximize summer cooling and minimize winter cool island effects, conserving large core green areas and integrating small green patches and corridors is essential, creating a spatially aggregated, well-connected, and continuous core structure. These findings offer theoretical and practical insights for climate-adaptive urban park design, contributing to improved urban thermal environments and enhanced urban resilience.