Isro study identifies Ahmedabad’s heat islands

Ahmedabad: A new study by scientists at Isro's Space Applications Centre has found significant temperature disparities within Ahmedabad, known as Intra-Urban Heat Islands (IUHI). The study employed a mobile vehicle equipped with a HOBO thermo-hygrometer to measure air temperature in various zones, including commercial areas, residential localities, near water bodies and in green spaces.
The mobile experiments by Neeru Jaiswal, Sanjib Deb, Sambit Panda Anup K Mandal, Aman Khan and C M Kishtawal of the Atmospheric and Oceanic Sciences Group at Isro-SAC demonstrated noticeable temperature variations, sometimes within a distance of less than 1km.These variations were particularly prominent in urban areas, traffic junctions, market zones, and near water bodies. A 2.5°C difference was noted within a 10km range through Ahmedabad's central region.
The team measured temperature during month of May since 2019, focusing on how urban structures and green spaces contribute to heat exposure. "Areas with higher vegetation, water bodies or barren land displayed a cooling effect." the study states. Temperature dropped by 0.8°C near Ghuma, while rose by 1.5°C as the vehicle passed through Bopal market.
It further adds, "The temperature at traffic junctions is higher by 1°C than in nearby areas." Areas like Vikram Nagar, Sanand and Paldi showed temperature variations due to a combination of vegetation, market activity and traffic conditions.
The measurements showed temperature differences were higher during night-time than during the day.
Compared to rural areas the transect nighttime temperature was up to 6°C higher in urban areas, particularly in regions like Satellite Road and Kalupur, and 4°C higher in areas like Bopal and Teen Darwaja
While measuring temperatures from SAC Bopal campus to the IIT Gandhinagar campus (40km) between 11.45 am and 3.25 pm, a maximum difference of 1.43°C between 12 noon and 12:30 midnight was noticed.
During a night measurement while moving between SVP airport to the railway station via Bopal-Ghuma, significant temperature variations were observed, with higher temperatures on busy market roads (38.39°C) and lower temperatures (33.16°C) in less populated areas like Ghuma. The temperatures measured along the route showed significantly higher temperatures than the urban of up to 5°C and in urban areas and of up to 6°C in rural sites, with a maximum difference of 5.84°C near the Satellite area at 9pm. The urban reference site had higher temperatures than the rural site, with the transect recording a maximum of 38.3°C near Teen Darwaja at 9:55pm.