Wet Bulb temperature is the scariest part of climate change you’ve never heard of
Wet bulb temperature is one of those features of climate change caused by global warming that often gets left out when discussing the radical changes our planet is going to experience in the coming years. Discussion has largely focused on issues such as drought, hurricanes, tornadoes, storm activity, and even unusual cold. The impacts of increased heat have been left out because we assume, incorrectly it turns out, that human beings can adapt to moderate increases in global temperature.
This turns out to be false, particularly in areas prone to hot and humid weather. It all comes down to one measure: wet bulb temperature. Wet bulb temperature is the one factor, more than any other, that can render entire regions uninhabitable.
Wet bulb temperature is essentially the temperature of a wet thermometer bulb such that the water is able to evaporate into the air. As the water on the thermometer bulb evaporates, it carries heat away from the thermometer. Therefore, unlike with a dry bulb thermometer, which measures ambient heat, a wet bulb thermometer measures the temperature of air if it were cooled such that its humidity reached 100%, at which point evaporation stops.
You can measure it using a device called a sling psychrometer:
