Two bloggers have made a stunning claim that has spread like wildfire on the Internet: They say the Northern Hemisphere jet stream, the high-altitude river of winds that separates cold air from warm air, has done something new and outrageous. They say it has crossed the equator, joining the jet stream in the Southern Hemisphere. One said this signifies that the jet stream is ‘wrecked’, the other said it means we have a ‘global climate emergency’. To be clear, the hypothesis that global warming is destabilizing the polar jet stream is a legitimate idea that has been published in peer-reviewed journals,though it remains controversial. But even the scientist who developed the hypothesis, Jennifer Francis, a professor of meteorology at Rutgers University, suggested it had been misapplied by Scribbler and Beckwith. "I’d say cross-equator flow cannot be unprecedented, maybe not even all that unusual," she said.
/ / / Claim that jet stream crossing equator is ‘climate emergency’ is utter nonsense