Mumbai has experienced the highest increase in sea levels among 15 Indian coastal cities, with a rise of 4.44 cm from 1987 to 2021. This finding is detailed in a report titled ‘Sea Level Rise Scenarios and Inundation Maps for Selected Indian Coastal Cities,’ released by the Bengaluru-based think tank, Center for Study of Science, Technology and Policy (CSTEP).
The report details sea level changes for 15 Indian coastal cities and towns under both historical and future climate scenarios. Mumbai leads with a rise of 4.44 cm, followed by Haldia at 2.726 cm, Visakhapatnam at 2.381 cm, Kochi at 2.213 cm, Paradip at 0.717 cm, and Chennai at 0.679 cm.
Sea levels are expected to continue rising across all 15 cities and towns through the end of the century under all scenarios, with Mumbai facing the highest increase. By 2100, sea levels are projected to rise by 76.2 cm in Mumbai, 75.5 cm in Panaji, 75.3 cm in Udupi, 75.2 cm in Mangalore, 75.1 cm in Kozhikode, 74.9 cm in Kochi, 74.7 cm in Thiruvananthapuram, and 74.7 cm in Kanniyakumari, even under a medium-emission scenario.
The study also examines potential inundation areas in these cities based on the Intergovernmental Panel on Climate Change's (IPCC) medium- and high-emission Shared Socio-economic Pathway (SSP) scenarios for the years 2040, 2060, 2080, and 2100.
According to a report of Indian Express, the SSP scenarios analyze how socio-economic factors like population growth, education, and urbanization could influence greenhouse gas emissions over the next century and, consequently, climate change. The study categorized cities and towns into Tier-I (Chennai and Mumbai), Tier-II (Thiruvananthapuram, Kochi, Mangaluru, Visakhapatnam, Kozhikode, and Haldia), and towns (Kanniyakumari, Panaji, Puri, Udupi, Paradip, Thoothukudi, and Yanam).
The study also highlights that by 2040, more than 10% of the land area in Mumbai, Yanam, and Thoothukudi, between 5% and 10% in Panaji and Chennai, and 1% to 5% in Kochi, Mangalore, Visakhapatnam, Haldia, Udupi, Paradip, and Puri is expected to be submerged due to rising sea levels.