Dampak Urban Heat Island Terhadap Heat Stress Masyarakat Kota Surabaya Menggunakan Temperature Humidity Index

Abstract

Urban Heat Island is one of the main urban climate issues caused by the expansion of built-up areas, vegetation loss, and intensive human activities. Surabaya, as a metropolitan city, has high population density, economic activities, settlements, industrial zones, commercial areas, and rapidly developing urban infrastructure, making it vulnerable to increasing surface temperature. This study aims to analyze the spatial distribution of Urban Heat Island, examine Temperature Humidity Index conditions, and assess the relationship between Urban Heat Island and Temperature Humidity Index in Surabaya City in 2017-025. This research uses a quantitative approach based on spatial analysis and regression. The data consist of Landsat 8/9 OLI/TIRS imagery from 2017-2025 to derive Normalized Difference Vegetation Index, Land Surface Temperature, and Urban Heat Island, as well as air temperature and relative humidity data from BMKG to calculate the Temperature Humidity Index. The relationship was analyzed using Ordinary Least Squares and Geographically Weighted Regression. The results show that high surface temperature is mainly distributed in dense built-up areas, industrial zones, settlements, and the northern coastal part of the city. The Temperature Humidity Index distribution indicates that uncomfortable areas reached 33.595,75 hectares, equivalent to the entire city of Surabaya. Ordinary Least Squares analysis indicates that Urban Heat Island has a positive and significant effect on the Temperature Humidity Index, with an R² value of 0,0904093. Meanwhile, Geographically Weighted Regression produced an R² value of 0,8836, indicating its stronger ability to explain the spatial variation in the relationship between the two variables. These findings confirm that increasing Urban Heat Island intensity is associated with higher Temperature Humidity Index values, although the strength of this relationship varies across locations depending on urban environmental characteristics.