Health co-benefits of differently sized and structured public parks in Munich (Germany), as nature-based solutions for climate adaptation

Public parks are a critical measure to adapt cities to climate change while providing valuable co-benefits that promote human wellbeing. To realize these potentials, we need to understand how the spatial configuration of parks is linked to their health-promoting potentials. To identify synergies and trade-offs between the health co-benefits, we applied methods from forestry, urban climatology, environmental psychology, and public health. We selected 61 plots in 36 public parks in Munich, Germany. The parks cover a gradient in size and vegetation structural complexity, ranging from sparse to forest-like. To characterize the vegetation structure, we applied mobile laser scanning, and to investigate the local cooling effects, we monitored the microclimate in the park plots and in their urban surroundings. To describe the subjective thermal comfort, activities, and mental restoration, we observed and surveyed visitors in the plots. Parks with a complex vegetation structure provided up to 3.3 °C cooling on hot days, while parks with low complexity were partially warmer than their surroundings. While large parks generally provided greater cooling, vegetation complexity partially compensated for the size differences. Regardless of size, old parks with high trees and a large canopy cover were key to urban cooling. The mental restoration was high across all parks. Large parks were perceived as slightly more restorative, while vegetation complexity had no direct impact. Parks with moderate vegetation complexity indirectly enhanced restoration by promoting higher thermal comfort and inviting for longer visits. Activity patterns varied with size: small parks encouraged social and cultural interactions while large parks favored strolling. Overall, we conclude that small parks with moderate vegetation complexity serve as effective climate adaptation measures, offering cooling and thermal comfort on hot days while supporting activities that promote mental wellbeing year-round.