Quantifying Spatial Urban Park Cooling Efficiency and Blue-Green Infrastructure Performance in Tropical Megacity Using Advanced Remote Sensing

Urban Heat Island (UHIs) are becoming increasingly extensive in tropical megacities, highlighting the need for efficient Blue-Green Infrastructure (BGI) to control surface temperatures and enhance urban climate resilience in Kuala Lumpur. Therefore, this study estimates BGI in Kuala Lumpur’s five parks using Landsat for monthly temperatures from 2014 to July 2025 and geospatial indices and ECOSTRESS-based temperatures from June to July 2025 for the urban park cooling intensity (UPCI). Bukit Jalil Recreational Park (BJRP) and Permaisuri Lake Garden (PLG) demonstrated the strongest synergy between vegetation and moisture, with the median land surface temperature (LST) (31.1 °C to 31.4 °C), the highest vegetation index (>0.26), moisture index (~0.27), and significant negative correlations with LST (r ≈ −0.6). Due to built-up and nighttime light, Kuala Lumpur City Centre Park (KLCCCP) recorded an LST exceeding 36 °C, low vegetation (0.18), and average moisture levels (0.17). Parks with water features, like Botanical Garden and Taman Tasik Titiwangsa (TTT), had LSTs 4 °C to 6 °C lower than adjacent built-up. According to UPCI, KLCCP recorded the highest cooling at 300 to 400 m (−0.92 °C), while BJRP experienced warming, with the UPCI increasing to +0.57 °C. Patch density analysis indicated that less fragmented, moisture-rich vegetation provides better cooling. These analyses suggest global transferable climate warming for tropical megacities and discuss how integrated BGI may propose practical, data-driven urban planning and climate-responsive redesign methods to decrease UHI and enhance climate resilience.