Heat spells set to raise mortality, say experts
The Intergovernmental Panel on Climate Change’s working group II report titled “Climate Change 2022: Impacts, Adaptation and Vulnerability” released in March has already flagged that Asia is experiencing high human mortality due to heat extremes.
“Climate change is increasing vector-borne and water-borne diseases, undernutrition, mental disorders and allergic diseases in Asia by increasing the hazards such as heatwaves, flooding and drought, air pollutants, in combination with more exposure and vulnerability. In addition to allcause mortality, deaths related to circulatory, respiratory, diabetic and infectious disease, as well as infant mortality are increasing with high temperature. Increases in heavy rain and temperature will increase the risk of diarrhoeal diseases, dengue fever and malaria in tropical and subtropical Asia. More frequent hot days and intense heatwaves will increase heat-related deaths in Asia,” the authors of that report wrote.
The report’s summary for policy makers also said: “Widespread, pervasive impacts to ecosystems, people, settlements, and infrastructure have resulted from observed increases in the frequency and intensity of climate and weather extremes, including hot extremes on land and in the ocean, heavy precipitation events, drought and fire weather.”
These heatwave spells will almost certainly increase mortality and morbidity, degrade ecosystems, lead to crop failure and loss of productivity and economic output.
“The first thing to do is a mortality analysis which shows at what temperature level mortality is rising. Correlating maximum temperature data with all cause mortality is a good indicator. A similar exercise has already been done in Ahmedabad which led to development of the Ahmedabad Heat Action Plan,” said Dr Dileep Mavlankar, who heads the Indian Institute of Public Health in Gandhinagar.
“Once an alert system is developed, based on the temperature threshold at which deaths start rising, people need to be reminded that they cannot work outdoors during peak afternoon hours; need to wear light-coloured clothes; wipe their bodies with a wet cloth; and rest every 30-60 minutes while working outdoors,” he added.
Dr Mavlankar highlighted that among various impacts, loss of productivity will be stark leading to widespread economic impacts. India already loses around 101 billion hours a year on account of heat, the most in the world, and risks seeing this number rise to 230 billion hours a year when global warming reaches 2 degrees C over pre-industrial levels, a paper published in Nature last year said. That’s the equivalent of the work done by around 35 million people each working an eighthour day, in a year.