Wet bulb temperature crosses safe threshold in city

CHENNAI: The sweltering heat in the city has crossed dangerous levels as the ‘wet bulb’ temperature has crossed the safe level of 30 degrees Celsius for the first time. As the El Nino factor continues in the Eastern Pacific Ocean, it is feared that the situation would worsen.

According to Poovulagin Nanbargal, an environmental organisation, that has a wet bulb temperature at its office, the wet bulb temperature in Chennai was registered at 31.3 degree Celsius which is higher than the safe threshold of 30 degree Celsius, on Sunday. On Tuesday, Kodambakkam registered a wet bulb temperature of 32.8 degrees Celsius.

Prabhakaran Veeraarasu, environmental engineer attached to the organisation, said incidents of wet bulb temperature breaching the safe level have been recorded in a few areas in north India and Pakistan for the last few years. “However, it is the first time that Chennai has crossed the safe level. The city will witness higher temperatures next month due to El Nino,” he said.

When the wet bulb temperature increases, the ability of the human body to sweat will be hampered and the body would not cool down. Higher temperatures and a higher percentage of humidity will increase wet bulb temperature. It may be noted that the Regional Meteorological Centre has issued a heat stress warning for isolated places in Tamil Nadu and Puducherry.

Prabhakaran said the reason for the increasing wet-bulb temperature is global warming as the world has already warmed by 1.2 degrees Celsius. It may be noted that the nations have adopted a resolution to prevent global warming from crossing 1.5 degrees Celsius by 2050. “Apart from this, urban areas, due to higher concretisation, would record higher temperatures by at least 1 degree Celsius,” he explained.

It may be noted that healthy adults could stay alive outdoors for only 6 hours when the wet bulb temperature is more than 35 degree Celsius. Vulnerable people could only withstand 30 degrees Celsius.

With the heat-related deaths in the State not being properly accounted for, he urged the government to safeguard the people from the heat by opening special wards in government hospitals to treat heat-related illnesses. “Also, the government should hold study to identify areas that breaches wet bulb temperature levels,” he said.