IPCC report: Heat, humidity, sea rise to make India uninhabitable if emissions not cut

* Several cities, including Chennai, Bhubaneshwar, Patna and Lucknow, approaching dangerous levels of heat and humidity.

These are some of the warnings the Intergovernmental Panel on Climate Change (IPCC) has for India in its latest report.

The IPCC released the second part of its sixth assessment report on Monday. It deals with climate change impacts, risks and vulnerabilities, and adaptation measures. For the first time, the panel has come out with regional assessments, even focussing on mega-cities, in its report. India is one of the most vulnerable countries globally in terms of the population that will be affected by sea-level rise, IPCC reports.

“Hot extremes including heatwaves have intensified in cities, where they have also aggravated air pollution events and limited functioning of key infrastructure,” the report notes. “Observed impacts are concentrated amongst the economically and socially marginalised urban residents… Infrastructure, including transportation, water, sanitation and energy systems have been compromised by extreme and slow-onset events, with resulting economic losses, disruptions of services and impacts to well- being.”

“Globally, heat and humidity will create conditions beyond human tolerance if emissions are not rapidly eliminated; India is among the places that will experience these intolerable conditions,” it says.

Prof Anjal Prakash, one of the lead authors on the chapter on cities, settlements and key infrastructure in the report, said: “Urban India is at greater risk than other areas with a projected population of 877 million by 2050, nearly double of 480 million in 2020. Currently, urbanisation in the country is at 35 per cent, which is likely to increase to 40 per cent in the next 15 years. Mega-cities are growing faster, and even smaller centres are growing rapidly.

“Simply the concentration of population in these cities make these settlements extremely vulnerable to climate change.”

The report refers to wet-bulb temperatures, a measure that combines heat and humidity. A wet-bulb temperature of 31 degrees Celsius is extremely dangerous for humans, while a value of 35 degrees is unsurvivable for more than about six hours, even for fit and healthy adults.

At present, wet-bulb temperatures in India rarely exceed 31 degrees C, with most of the country experiencing maximum wet-bulb temperatures of 25-30 degrees C, according to IPCC. It notes that if emissions are cut, but only by the levels currently promised, many parts of northern and coastal India would reach extremely dangerous wet-bulb temperatures of over 31 degrees C towards the end of the century. If emissions continue to rise, wet-bulb temperatures will approach or exceed the unsurvivable limit of 35 degrees C over much of India, with the majority of the country reaching wet-bulb temperatures of 31 degrees C or more.