Spatiotemporal Trends of Land Surface Temperature and Surface Urban Heat Island Intensification Across India

Dense population, rapid urbanization, and industrialization make India a highly vulnerable country to the consequences of global warming. This study examines past 25 years (2000–2024) spatiotemporal trends of diurnal Land Surface Temperature (LST) and analyses the Surface Urban Heat Island (SUHI) intensities across the country, and for 50 major cities, respectively, including the influence of zonal biogeography. The significance of the LST trends is statistically confirmed by using the Mann–Kendall test and zonal heterogeneity is analysed by using ANOVA. The study covers total span of 25 years (2000–2024) which is classified in two periods, pre-COVID-19 years (2000–2019) and including the post-COVID-19 years (2000–2024). In the period, 2000–2019, the mean LST variability range of (minimum to maximum) has substantially widened by 7.8°C (2.3°C) for day-time (night-time). The LST change during the COVID-19 period has significantly hindered, change in day-time and night-time LST for May month is 0.18°C and 0.04°C, respectively, whereas, during 2020–2024 it has become − 1.24°C and − 0.2°C, respectively. In general, the zones follow the country-level LST trends for 2000–2019 as well as for 2020–2024 periods, with variable LST change rates. The highest annual day-time LST growth (+ 0.15 year ^− 1 ) is observed for the Desert (DES) zone, whereas the highest night-time LST rise (+ 0.07 year ^− 1 ) is observed for the Western Ghats (WG). Notably, the Himalaya and Trans-Himalaya (HTH) zones exhibit negative LST growth rate (-0.08 and − 0.09 for day- and night-time, respectively). Further, SUHI analysis indicates that the cities within the Indo-Gangetic Plain (IGP), Semi-Arid Region (SAR), Deccan Plateau (DP), and Western Coastal Region (WCR) zones are found to be largely impacted by SUHI intensification, ranging between 2–5°C (4–7°C) for day-time (night-time). Cities in the rest of the zones experience SUHI values in the range of 1–3°C (4–5°C) for the day-time (night-time). Interestingly, even trivial SUHI values of DES cities (1–3°C for day-time) could be consequential, as the zonal LST are extremely high. The SUHI analysis also indicates that the night-time SUHI values are consistently higher and more relevant than the day-time. The study points out the requirement of urgent policy intervention and mitigation measures.