The rise in heat will scorch not only the surface but will also manifest in the city’s ambient temperatures during summers. These are the disquieting findings of a study carried out by the researchers of earth sciences from IIT- Roorkee and National Institute of Advanced Studies, Bengaluru.
Today, we feel run down when the mercury is at 41°C. So imagine winters when 40% of the city’s surface and ambience is blasted by 35°C heat. That is the projection of the study.
The researchers compiled a heat map of areas such as Sarkhej, Shilaj, parts of Sola, Chandkheda, Motera, Tragad, Amiyapur, Ognaj, and parts of Sabarmati. In these places, researchers said, temperatures may peak to 45°C. In areas such as Gota, Jagatpura, and Ambli, temperatures will shoot up to 40°C. That will be the case in several other spots in the western areas of the city.
On the east of the river, the airport area, Hansol, Shawadi, Piplaj, Narol Gam, Vatva, Isanpur, Maninagar, Behrampura, the Calico Mills area, Khodiyarnagar, Indira Nagar, and Lambha will have to endure temperatures up to 45°C. In 2020, in the majority of the spots listed above, average ambient temperatures hovered between 35°C and 40°C during summers.
“Our findings suggest an addition in the built-up or constructed area in Ahmedabad of about 5.77% and 13.08% by 2025 and 2030 respectively,” the researchers said. “This may lead to the deduction of cropland area of about 4.15% and 12.54% for the two years respectively.”
The researchers are Pir Mohammad, Ajanta Goswami, and Sarthak Chauhan of IIT-Roorkee; and Shailesh Nayak of National Institute of Advanced Studies.
The researchers said that excessive urban growth in the areas studied will cause an overall rise in the land surface temperature (LST) that might breach even the 45 °C mark. The researchers used the Artificial Neural Network (ANN) based Cellular Automata (CA) model to predict the LULC (Land Use /Land Cover) and ambient temperatures for 2030. They said the model’s accuracy is 89.2%.
According to Nayak and Mohammad: “An increase in the green space area and avoidance of non-impermeable surfaces is suggested in the future to mitigate the Urban Heat Island (UHI) phenomenon.”
The researchers said: “The outcome of the research can help urban planners and policymakers while formulating urban heat island related mitigation strategies in the near-future scenario.”
The researchers had analyzed a series of LandSat earth observation satellites’ data produced since 2010 and concluded that dense urban centres such as Ahmedabad are witnessing an enormous change in the LULC across several clusters in the metropolitan area. This is leading the LST rise, which in turn is intensifying the UHI phenomenon across the city.