In 3 decades, Ahmedabad’s mean land surface temp has risen by 3.4°C: Study

Ahmedabad: If summers of recent past have been unbearable, there are reasons. While the average general temperature during the hotter months of an year has gone up, factors ranging from loss of vegetation, rise in built environment, and urban heat island phenomenon have contributed to it. Monday’s scorching 44.3 in Ahmedabad also points to clues in other recent studies, which are helping decode the phenomenon, while including a key factor — land surface temperature (LST) — which is different from the average general temperature.A study, ‘Spatial-temporal analysis of land surface temperature in Ahmedabad city using Landsat-derived indices and machine learning-based regression assessment (1995–2025)’ shows a key change over three decades. Things have heated up when it came to land surface temperature (LST) by no less than 3.4 degrees celcius between 1995 and 2025. For the study, published recently in the Elsevier journal Dynamics of Atmospheres and Oceans, researchers Poornima Suthar and Bina Patel from the Environmental Engineering Department of LD College of Engineering took Landsat-derived indices including LST and Normalized Difference Built-up Index (NDBI) among others for the three decades studied.The study’s abstract reads, "Seasonal and decadal analyses reveal a steady increase in LST, with summer mean temperatures rising from 36.47 °C (1995) to 39.87 °C (2025) and winter temperatures increasing from 23.14 °C to 29.53 °C.’ It thus indicates about 3.4 degrees rise in average summer and 6.4 degrees rise in average winter LST in Ahmedabad. The concept is slightly different from the daily temperatures the India Meteorological Department (IMD) provides, said experts.The study highlights an interplay of factors such as vegetation, water bodies, moisture, and built-up areas while recommending multi-variable heat-resilient planning.A separate analysis of the OpenCity data for the maximum temperatures for Ahmedabad captured at the Airport station indicates that between 1995 and 2004, the average maximum temperature was 37.1 degrees and rose to 38.4 degrees between 2015 and 2024. Days with 40 degree-plus temperatures also rose steadily.Another study by Mahi Patel, Devansh Desai and Zalak Shah from Silver Oak University published in 2025 using LST data shows that "pre-monsoonal heat stress increased from 39.32°C in 2014 to 41.29°C in 2023.” A study by experts from Auburn University and Jahangirnagar University assessed the change in land cover change in South Asian cities and indicated that from mean annual temperature of 36.17°C in 2003, the city recorded rise to 38.75°C in 2023 a decade later, which correlated to rise in area covered in built environment.“LST and its correlation with various factors has been a topic of study for long, and it comes in handy while planning the city and provides for measures such as increase in blue-green infrastructure, heat sinks, and passive cooling methods,” said an urban planner in the city.