| it will not take days and months. one heat wave will kill hundreds of thousands of people in their sleep. and how and where will a few hundred million people migrate? [..]Currently, about 2 percent of the Indian population is occasionally exposed to extreme wet-bulb temperatures (between 89 and 94 degrees). According to a 2017 study, by 2100 that number could increase to 70 percent. [..] https://scroll.in/article/931865/the-human-body-cant-cope-in... : Human body can’t cope infinitely with rising temperatures – and in India, it is close to its limits
At a certain temperature, sweat stops evaporating – shutting down the body's cooling mechanism, causing death. Parts of the world are already there. When the air temperature exceeds 35 degrees Celsius, the body relies on the evaporation of water – mainly through sweating – to keep core temperature at a safe level. This system works until what is called the wet-bulb temperature reaches 35 degrees Celsius. The wet-bulb temperature includes the cooling effect of water evaporating from the thermometer and so is normally much lower than the normal dry-bulb temperature reported in weather forecasts. Once this wet-bulb temperature threshold is crossed, the air is so full of water vapour that sweat no longer evaporates. Without the means to dissipate heat, our core temperature rises, irrespective of how much water we drink, how much shade we seek, or how much rest we take. Without respite, death follows – soonest for the very young, elderly or those with pre-existing medical conditions. Wet-bulb temperatures of 35 degrees Celsius have not yet been widely reported, but there is some evidence that they are starting to occur in South West Asia. Climate change then offers the prospect that some of the most densely populated regions on Earth could pass this threshold by the end of the century, with the Persian Gulf, South Asia and most recently the North China Plain on the front line. These regions are, together, home to billions of people.[...] |
Peak temperatures don't occur during the night. How do you figure heat wave will kill people in their sleep?