About a week ago, Facebook feeds lit up with the news: The jet stream is now "wrecked," running pole to pole and confusing summer with winter. The source was a blog post by Robert Fanney, and within the first paragraph, my debunk spidey senses were positively tingling… In fact, the opposite may be true. "The polar jet is the one that we expect to weaken in response to a rapidly warming Arctic, as this differential warming will reduce the north-south temperature difference between the Arctic and mid-latitudes, and it’s this temperature difference that fuels the polar jet," wrote Jennifer Francis, an atmospheric scientist at Rutgers. "Interestingly, the upper levels of the tropics are also warming faster than are mid-latitudes, which increases the temperature difference between them and the tropics, which leads to a stronger jet. The topic of this article is mixing up the two jets and how they are being affected by greenhouse-gas-induced warming."
/ / / Don’t Freak Out About Jet Streams Crossing the Equator