Glass buildings, densely populated slums and an airport are the key reasons for the urban heat in Mumbai, revealed a data jam by citizens, which assessed the reasons of urban heat in Mumbai’s five wards.
OpenCity.in, the civic-tech programme of the Oorvani Foundation and the State Climate Action Cell of the Government of Maharashtra conducted a data jam on ‘Urban Heat in Mumbai’ on Saturday. Participants discussed some unique problems of Mumbai like the densely populated slums, railway network running through the city and rapidly decreasing urban forest cover. Various short-term and long-term solutions like vertical gardens, planting trees along pedestrian ways, incentivising green architecture and ventilation corridors were discussed.
Five teams of citizens took different areas of the city, studying the urban fabric of the locality to analyse the heat exposure and vulnerability in the G/South, P/North, L, H/East and M/East wards of the city. The hyperlocal issues like commercial glass buildings in the business district of Bandra-Kurla Complex, the densely populated slums in Shivaji Nagar, the presence of the airport in Andheri east were found to be some of the major issues of the increasing heat in the city. They noted that areas like informal settlements bear the brunt of urban heat during the hot months followed by industrial areas. Areas closer to greenery like the Sanjay Gandhi National Park benefited from the greenery and were much cooler than the surroundings.
The teams delved into the social and economic vulnerabilities in the wards by correlating heat data from satellites with data from the census 2011 like percentage of people belonging to scheduled castes and scheduled tribes, the roof material usage in the wards and the number of people employed in the wards. They also correlated with the vegetation cover and built-up index as per satellites and noted how greenery and high buildup have a marked difference on urban heat.
The day-long jam in Mumbai saw 25 participants including GIS experts, students, engineers and active citizens use data on heat, environmental parameters like particulate matter, and other relevant public data to understand the changing heat patterns in Mumbai with the intention to propose mitigating and adaptive solutions. Multiple organisations partnered to organise the event including Heatwave Action Coalition, C40 Cities, Climate Group, Blue Ribbon Movement, and St. Xavier’s College, Mumbai.
Shilpa Shashidaran, manager of climate implementation of C40 Cities said, “Datajam is a wonderful platform to bring people from diverse sectors together to translate the vast pool of publicly available data into usable actions for policymakers and citizens. Such events are also a great avenue for raising awareness and understanding the gaps for working on such critical climate risks such as urban heat.”
Sarita Fernandes, climate fellow with the Maharashtra State Climate Action Cell, said, “Citizen science spaces are limited in climate action and access to them is a challenge. Data jams bridges the gap between policy and people, data and its impacts and is a long-term solution to climate action”
Ward-wise Datajam Outputs:
H/East: Diverse ward with the airport, commercial areas like BKC and informal settlements. No healthy vegetation was found in the area as per definitions of Normalized Difference Vegetation Index (NDVI). However, a little green cover reduced the temperature by 6 to 7 degrees. Around 73% of the population lives in slums, and the slums did not have any green cover.
M/East: Deonar’s large dumping ground, informal settlements like Shivaji Nagar, gated communities like Chembur, and major industrial hubs, all coexisting with mangroves. They analysed heat at neighbourhood level and noted that spread out density like slums leads to high heat, while vertical growth is better in terms of heat.
L: Industrial settlements and urban poor settlements. Chandivali’s informal settlement recorded 48 degrees and was the hottest part of the ward, mainly because of high density, asbestos roofing, lack of greenery and open spaces and also being very close to the airport. They highlighted the lack of AC buses passing through the ward and noted that they serve only the main corridors.
P/North: The presence of greenery from the Sanjay Gandhi National Park in the East, and mangroves and creeks on the west while the population is crammed in the centre at high density. From 2015, the average heat they have been exposed to has gone from 42 degrees to 50 degrees and more areas are facing heat as green areas are being encroached.
G/South: A high variance in heat across the ward. Lower Parel, Elphinstone, Worli Koliwada and BDD Chawls had the highest temperature. The southern part is greener and is much cooler which also includes the Mahalaxmi Race Course.
