A strange thing happened in the stratosphere

A strange thing happened in the stratosphere
A predictable pattern of winds in the stratosphere recently changed in a way scientists had not seen in more than 60 years of record-keeping. Credit: NASA

This disruption to the wind pattern - called the "quasi-biennial oscillation" - did not have any immediate impact on weather or climate as we experience it on Earth's surface. But it does raise interesting questions for the NASA scientists who observed it: If a pattern holds for six decades and then suddenly changes, what caused that to happen? Will it happen again? What effects might it have?

"The quasi-biennial oscillation is the stratosphere's Old Faithful," said Paul Newman, Chief Scientist for Earth Sciences at NASA's Goddard Space Flight Center, Greenbelt, Maryland, and lead author on a new paper about the event published online in Geophysical Research Letters. "If Old Faithful stopped for a day, you'd begin to wonder about what was happening under the ground."

Winds in the tropical stratosphere, an atmospheric layer that extends from about 10 to 30 miles above Earth's surface, circulate the planet in alternating easterly and westerly directions over roughly a two-year period. Westerly winds develop at the top of the stratosphere, and gradually descend to the bottom, about 10 miles above the surface while at the same time being replaced by a layer of easterly winds above them. In turn, the easterlies descend and are replaced by westerlies.

This pattern repeats every 28 months. In the 1960s scientists coined it the "quasi-biennial oscillation." The record of these measurements, made by weather balloons released in the tropics at various points around the globe, dates to 1953.

The pattern never changed - until late 2015. As the year came to a close, winds from the west neared the end of their typical descent. The regular pattern held that weaker easterly winds would soon replace them. But then the westerlies appeared to move upwards and block the downward movement of the easterlies. This new held for nearly half a year, and by July 2016 the old regime seemed to resume.

"It's really interesting when nature throws us a curveball," Newman said.

The quasi-biennial oscillation has a wide influence on stratospheric conditions. The amount of ozone at the equator changes by 10 percent between the peaks of the easterly and westerly phases, while the oscillation also has an impact on levels of polar ozone depletion.

With this disruption now documented, Newman and colleagues are currently focused on studying both its causes and potential implications. They have two hypotheses for what could have triggered it - the particularly strong El Ni├▒o in 2015-16 or the long-term trend of rising global temperatures. Newman said the scientists are conducting further research now to figure out if the event was a "black swan," a once-in-a-generation event, or a "canary in the coal mine," a shift with unforeseen circumstances, caused by climate change.


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More information: P. A. Newman et al. The anomalous change in the QBO in 2015-2016, Geophysical Research Letters (2016). DOI: 10.1002/2016GL070373
Journal information: Geophysical Research Letters

Citation: A strange thing happened in the stratosphere (2016, September 2) retrieved 14 October 2019 from https://phys.org/news/2016-09-strange-stratosphere.html
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Sep 02, 2016
That is when Trump first started breaking wind

Sep 02, 2016
That is when Trump first started breaking wind

if that were the case all our ills would be cured. Instead we are cursed with Lying Hillary, stinking, cursed, crooked, Hillary.

Sep 02, 2016
This comment has been removed by a moderator.

@tinitus: indeed, if continuing the downhill path with our unintelligent overpopulation we might reach the point of our oxygen and atmosphere collapsing. Something with a precedent, when assuming that the following report might be factual:
http://www.future...port_476

Sep 03, 2016
The Earth is surrounded with http://i.stack.imgur.com/Zbz0g.png, but this number could raise, if the global warming will continue. It could disrupt the climate, as we know it.

Yes, maybe in a good way for a change.

Sep 03, 2016
Re SST above
The link is to Mayan calendar woo.

Sep 04, 2016
Global temperatures have not risen at all.

Sep 04, 2016
The Earth is surrounded with http://i.stack.imgur.com/Zbz0g.png, but this number could raise, if the global warming will continue. It could disrupt the climate, as we know it.


U.S. Data Since 1895 Fail To Show Warming Trend http://nyti.ms/1nS5YgG

Sep 04, 2016
U.S. Data Since 1895 Fail To Show Warming Trend http://nyti.ms/1nS5YgG


A 25 year old New York Times article about US temperatures, 1.5 percent of Earths surface, that quotes the meteorologist who led the study as saying: -

"the findings concerning the United States do not necessarily ''cast doubt'' on previous findings of a worldwide trend toward warmer temperatures, nor do they have a bearing one way or another on the theory that a buildup of pollutants is acting like a greenhouse and causing global warming."

This is the third time you've posted this, did you even bother to read it or did you just get as far as the title?


Sep 05, 2016
You know what 27 year old news paper article is? Old, not news.

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