Lets talk Thermogeddon
December 23, 2010
This post is not only informative, but, for those who can’t wait until next year’s Talk like a Pirate day, (mark your calendar, 9/19/11) – listening to an Aus-trilian talk to a Kiwi is the next best thing.
For a quick lesson on comparing and contrasting Aussie and Kiwi dialects, see below:
Ok, I admit I’m stretching to find something amusing here. Sobering stuff.
Imagine the temperature outside is 100 degrees Fahrenheit. That’s hot. But as long as the humidity is low enough to allow you to perspire, you will be okay. For example, suppose the relative humidity is only 70 percent. Then the wet-bulb temperature is only 90 degrees — a full 10 degrees below the actual temperature and 5 degrees below your skin temperature. You may be hot, but you will survive as long as you have access to water.
But now suppose that the relative humidity is 85 percent instead of 70 percent. Now the wet-bulb temperature would be 96 degrees — one degree above your skin temperature, making it impossible for you to perspire without raising your skin temperature, which in turn would require you to raise you core temperature. Spend too much time under these conditions and you would be in trouble…
“Researchers from Purdue University and the University of New South Wales, Australia, have for the first time calculated the highest ‘wet-bulb’ temperature that people can tolerate – and have found that it could be exceeded for the first time in human history under reasonable worst-case climate change scenarios.”
“We found that … a 21-degree warming would put half of the world’s population in an uninhabitable environment,”says study co-author Matthew Huber of Purdue University.
While the Intergovernmental Panel on Climate Change found that the result of business-as-usual warming would be 7 degrees by 2100, eventual warming over several centuries of 25 degrees is feasible, says Huber.
The new research calculated the highest tolerable “wet-bulb” temperature that humans can withstand.
“The wet-bulb limit is basically the point at which one would overheat even if they were naked in the shade, soaking wet and standing in front of a large fan,” says study lead author Steven Sherwood of the University of New South Wales in Sydney.