Effects of Tree Arrangement and Leaf Area Index on the Thermal Comfort of Outdoor Children’s Activity Space in Hot-Humid Areas

Hot-humid areas have long, hot summers and poor outdoor thermal comfort (OTC). The urban heat island (UHI) effect exacerbates the deterioration of OTC in hot-humid areas, seriously affecting safety children’s activities. In this study, 60 scenes were simulated using ENVI-met based on different leaf area index (LAI) planting arrangements to explore how tree LAI affect small-scale environment during summer months assess Universal Thermal Climate Index (UTCI). research shows that (1) high trees optimize more than low trees, but can be planted multiple times achieve level optimization trees; (2) increasing number optimizes study area, reducing UTCI by up 3.7 °C with increased compared unshaded areas; (3) thickening shade east–west direction north–south direction, too much optimizing only 0.01%. This provides practical advice for design CAS areas.