Comprehensive Evaluation of Water-Retention and Cooling Capacities of Urban Green Space Under Different Climatic Conditions Across China

Urban green spaces play a crucial role in addressing pressing environmental challenges, such as alleviating the urban heat island effect and enhancing water retention. However, there remains a research gap in understanding the simultaneous benefits of water-retention and cooling capacities, especially under the diverse climatic conditions across China. Utilizing robust methodologies and remote sensing data, our study evaluates the dynamic interplay between aridity index (AI) and retention-cooling performances of urban green spaces in both cold and warm season from 2003 to 2018. Results demonstrated that water-retention capacity is more effective in relatively arid regions, whereas cooling capacity is more pronounced in humid regions, with both effects being largely season-dependent. In addition, green space proportion significantly influences the relationship between AI and retention-cooling performances, particularly for cooling capacity, which exhibits opposite trends between cold and warm seasons. Future projection analysis indicate that climate change scenarios could significantly alter retention-cooling performances, potentially leading to notable deviations from the patterns observed during the historical periods across different climate zones, with an increasing dependence on changes in local climatic conditions. The inconsistent performance of urban green spaces in terms of water-retention and cooling across seasons and various climate regions, highlighting the importance of context-specific greening strategies to sustain and enhance urban resilience to future climate change in China.