Climate change increasing chances of temperatures reaching 40 degrees Celsius on Holi: Analysis

New Delhi, March 22

The probability of temperatures soaring to 40 degrees Celsius around the festival of Holi late March has multiplied due to climate change, according to an analysis of temperature data since 1970.

Researchers at the US-based Climate Central, an independent group of scientists, conducted the analysis to place India within the context of global warming trends.

In the climate of the early 1970s, it would be exceedingly rare to encounter temperatures in late March above 40 degrees Celsius. Maharashtra, Chhattisgarh and Bihar had a more than 5 per cent chance of experiencing such temperatures, they said.

However, the analysis revealed that the chance of reaching 40 degrees Celsius has since expanded to include nine states: Maharashtra, Chhattisgarh, Bihar, Rajasthan, Gujarat, Telangana, Madhya Pradesh, Odisha and Andhra Pradesh. Maharashtra now has the highest probability at 14 per cent.

To show this change, the researchers calculated the difference between the warming rates in March and April, expressed as the change in average temperature since 1970.

The researchers said a total of 37 cities now have at least a 1 per cent chance of experiencing 40 degrees Celsius or warmer temperatures, and 11 cities have a 10 per cent or greater probability.

With the exception of Madurai, the 15 cities with the highest risk of experiencing temperatures above 4 degrees Celsius are in central India, the analysis showed.

Bilaspur faces the highest risk at 31 per cent, and its chances of reaching 40 degrees Celsius is now 2.5 times higher than in the 1970s.

Indore shows the largest change in risk, with an 8 per cent probability, 8.1 times higher than in the past.

Madurai and Bhopal also have very large changes (7.1 and 5.5 times higher, respectively) and relatively high overall risk (19 per cent and 12 per cent).

Climate Central said March and April are warming across India.

Every region considered had net warming during both March and April. During March, the northern and western regions have the fastest warming, with the largest change since 1970 in March occurring in Jammu and Kashmir (2.8 degrees Celsius).

Warming is more uniform in April and Mizoram has the largest change since 1970 (1.9 degrees Celsius).

“There has been an abrupt transition in the temperatures from cool winter-like temperatures to much warmer conditions now. After the strong warming trend observed in February, March is also likely to follow the same pattern. These warming trends in India are a clear sign of the impacts of human-led climate change,” said Andrew Pershing, vice-president for Science, Climate Central.

The average temperatures in states in north India showed either a cooling trend or slight warming in January, followed by strong warming in February. This indicates that these regions are now experiencing abrupt transitions from cool winter-like temperatures into much warmer conditions traditionally observed in March, the researchers said.

Climate science says the world needs to slash CO₂ emissions by 43 per cent by 2030 to limit the average temperature rise to 1.5 degrees Celsius, the guardrail to prevent worsening of climate impacts.

The business-as-usual scenario will take the world to a temperature rise of around 3 degrees Celsius by the end of the century, scientists have warned.