Temperature and humidity in Bangladesh will cross over into unsurvivable territory before the end of the century, a study published in Science Advances on Wednesday says.
The study was conducted by researchers collaborating from Hong Kong, China, and Los Angeles and Cambridge in the US. While there have been multiple climate change studies focusing on conventional temperature alone, this study used 'wet-bulb temperature' – the air temperature read when a wet cloth is wrapped around a thermometer – as a more accurate measure that took into account humidity, as well as the body's ability to release heat.
“The risk of human illness and mortality increases in hot and humid weather associated with heat waves,” the study said, noting that exposure to ambient wet-bulb (WB) temperatures of over 35 degrees Celsius would be deadly even “under shaded, well-ventilated conditions.”
While citing concrete evidence for human cause behind global warming, India and China were noted to be the biggest contributors in Asia in the study. Some simulations of the study suggested that parts of India, Pakistan and Bangladesh would exceed 35 degrees before the end of the century, while others suggested that WB temperature rises could be kept to 31 degrees which was still “considered extremely dangerous for most humans.”
The study pointed out the high humidity and lack of air conditioning in South Asia as further compounding the complex problem of tackling heat waves. It also noted that agricultural land would be hit the worst by the heatwaves, making the lives of agricultural workers difficult and reducing food production.
Around 4% of South Asia's population is expected to be exposed to the deadly 35 C WB temperatures, while almost 75% are expected to be exposed to the extremely dangerous 31 C by the end of the century, if steps are not taken to combat the rise in temperatures.