The amount of carbon dioxide in the air has an insignificant influence on temperature – and is not the real driver of extreme weather – Climatologist David Legates explained Wednesday.
“Carbon Dioxide isn’t a magic climate control knob;” it’s just “a bit player,” Legates said in an interview with The Daily Signal. At its current level – even if the amount of carbon dioxide doubled – it would cause “maybe, a degree Celsius of warming and that would be it,” Legates noted. “And, certainly, it’s not worth the economic impacts.”
Today, the fear is that global warming will lead to more disasters. But, as Legates recalled, in the 1970’s, it was claimed that “global cooling” was climate change and would cause climate disasters to increase:
“At that time, we were told that global cooling would bring about more hurricanes, more tornadoes, more floods, more droughts, more of all the disasters.”
“So the question is, which is it?” Legates asked rhetorically:
“Is it warmer conditions bringing you more disasters or is it colder conditions bringing you more disasters? Or were we statistically somehow on a saddle point that said it was perfect at the time and if we went warmer or colder, both would get worse?”
It’s actually none of the above, Legates said. Instead, disasters become more frequent when the disparity between the temperature at the equator and the temperature at the Earth’s poles increases, Legates said:
“The answer: what’s driving most of the storms and things that create variability is what we call the equator-to-pole temperature gradient. That is the how warm the equator is relative to the pole.
“Now, if you have a very warm equator and a very cold pole, you have a lot of temperature contrast, and that brings about a lot of storminess.”
“If, in an extreme world where the pole and equator were at the same temperature, global circulation would actually stop,” Legates explained.
Because a slight warming will warm the air at the poles more than it will warm the air at the equator (which is already warm), the difference in the temperatures decreases, which will lead to fewer disasters, Legates said:
“So a warmer world has a lessened equator-to-pole temperature gradient, which means the interactions of cold, dry air coming out of Northern Canada and warm, moist air coming out of the Gulf of Mexico, that contrast is diminished.
“That would diminish things like hurricane activity, that would diminish tornadoes.”
What’s more, “Civilization has always done better under warmer conditions,” because “a warmer “world is a less volatile weather world,” Legates said:
“You develop a civilization when you’re not looking for food, clothing, shelter, and security…you have, therefore, more time to develop the arts, to develop technology, develop all the things we think about with civilization.”
Nonetheless, climate change is, and always has been, inevitable, because “variability is built into the (Earth’s) system,” Legates said, citing the Roman Warm Period, the Medieval Warm Period, the Modern Warm Period, and the Earth’s Little Ice Age (which began in the 14th Century).
“The idea is that we are not a linear system. We are a nonlinear system that brings about chaotic, unpredictable behavior,” Legates said.