Global climate emergency called off
Claim that jet stream crossing equator is climate emergency is utter nonsense
I reached out to several atmospheric scientists, who have graduate degrees and are trusted sources in the profession, for their reaction to these claims. Without exception, they said air flow between the hemispheres is not at all uncommon.
“This is total nonsense,” said Cliff Mass, a professor of meteorology at the University of Washington. “Flow often crosses the equator.”
Mass added that the cross-equator flow identified by Scribbler and Beckwith is not between mid-latitude jet streams, as claimed. “The analysis is making mistakes that even one of my junior undergrads would not make,” Mass said.
Ryan Maue, a senior meteorologist with a doctoral degree who works at WeatherBell Analytics, agreed with Mass that the cross-equator flow is totally normal and not evidence of a joint hemispheric jet stream. “Cross-equatorial flow at both upper and lower levels is part of the seasonal transition of the Western Pacific monsoon through boreal summer,” he said.
“Sometimes the flows connect up with each other and make it look like a larger flow structure is causing the jet stream to flow from one hemisphere to the other, but it’s in no way unprecedented,” Roy Spencer, a professor of atmospheric science at University of Alabama-Huntsville, explained on his blog.
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.
Sam Lillo, who is working on his PhD in meteorology at the University of Oklahoma, said the cross-equator flow evolved from twin areas of high pressure on either side of the equator while a parade of atmospheric waves in the Southern Hemisphere had pushed the subtropical (which is distinct from the mid-latitude or polar jet stream that Scribbler and Beckwith are discussing) jet stream northward, allowing the link to occur. “None of this is unusual,” he said. “There isn’t a wall at the equator separating the two hemispheres, and air is free to flow from one side to the other.”
Scribbler had cited a tweet from Lillo to support his argument of a strengthened equator-to-pole connection, but Lillo countered that the tweet referred to some unusual behavior of a phenomenon known as the QBO or Quasi-Biennial Oscillation, which is “a separate story” from the cross-equator flow. The QBO, he said, is an oscillation in equatorial stratospheric winds, which has been “out of phase.” He chalked up the weird QBO behavior to natural variability “even though I’m an advocate for identifying connections to human-caused climate change.”
Unfortunately, the thoroughly specious claims of Scribbler and Beckwith have gone viral, getting picked up Raw Story, Reddit and Inhabitat.
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