By the end of this century it’s going to be hotter than ever – the average day temperature in Tamil Nadu, now 32.9 degree Celsius is likely to go up by 3.1 degree Celsius.
This was the finding of a study conducted by a team of researchers at the Centre for Climate Change and Adaptation Research (CCC&AR), Anna University.
Though Chennai’s maximum temperature will shoot up by 3.1 degree Celsius, residents of neighbouring Tiruvallur and Kancheepuram districts will be worse of, as the temperature there is likely to increase by 3.4 degree Celsius.
“Studies show that Chennai’s maximum temperature will increase by 0.9 degree Celsius and that of the neighbouring districts by 1 degree Celsius over the next 30 years,” explained A. Ramachandran, director of the centre, who led the team of researchers.
The projection model also shows that the minimum temperature in the State, which is 23 degree Celsius at present, is likely to go up by 3.5 degree Celsius. From March to May, the model indicates an increase in the percentage of days with the day temperature above 45 degree Celsius.
What may make city residents sweat even more are heat islands: patches of high temperature caused by heat being temporarily trapped by emissions of carbon monoxide, methane, aerosol and ground level ozone.
“If there is an increase in the levels of these gases, there will be more heat at that spot and people will be uncomfortably hot,” explained Prof. Ramachandran.
In the 1960s, Chennai’s heat islands were concentrated only in Ennore, Royapuram and a few other areas in the north. But later, T. Nagar was added to this list.
Last year, the centre found that Velachery, Perungudi and Medavakkam too had heat islands.
The model further found that interior districts including Salem, Dharmapuri, Erode, Coimbatore Tiruvannamalai, Vellore, Ariyalur and Perambalur are likely to be hotter than those in the coastal areas that have the advantage of the northeast monsoon.
With an increase in the heat, there is also a likelihood that the number of days that experience 25 mm of rain per day during the northeast monsoon will increase.
“The variations are increasing, which will create havoc. The model has used the behaviour of the atmosphere and the ocean to make predictions,” Prof. Ramachandran said.
By the turn of the century, Kanyakumari district would be the best place to live in as it has the advantage of both the northeast and the southwest monsoons, he said.
The study, which is a collaborative effort between the Met Office Hadley Centre, UK and the CCC&AR, Anna University, has used a regional climate model called PRECIS – Providing Regional Climates for Impacts Studies.
The study was released at a programme on Wednesday by Mohan Verghese Chunkath, secretary, department of environment and forests. Speaking on the occasion, he said that the data must be disseminated among the community, and ways should be found to help the community adapt to changes in climate.