The Earth sure is getting weirder all the time. Between some of the strange effects of climate change and undetected killer asteroids narrowly missing us, the Earth keeps proving that our understanding of the world and its surroundings only go so far before we enter the unknown. To make things stranger, scientists at NASA’s Goddard Space Flight Center recently detected an anomalous phenomenon in the stratosphere that they are struggling to explain.
According to the researchers' recent publication in Geophysical Research Letters, a regularly repeating wind pattern in the Earth’s stratosphere called the quasi-biennial oscillation (QBO) defied its usual pattern of alternating from westerly to easterly:
Normally, the QBO would show a steady downward propagation of the westerly phase. In 2015–2016, there was an anomalous upward displacement of this westerly phase [...] Comparisons to tropical wind statistics for the 1953 to present record demonstrate that this 2015–2016 QBO disruption is unprecedented.
The QBO is a cycle of alternating stratospheric wind direction that occurs roughly every 28 years, in which pressure gradients created by rising and falling easterly and westerly wind currents cause them to switch elevations within the stratosphere. NASA began tracking these currents, and has never once seen a deviation from the norm.
Paul Newman, chief of NASA Earth Sciences and lead author of the published data, stated in a NASA press release that the anomaly was a shock scientists who had been studying these regularly-repeating atmospheric patterns for decades:
The quasi-biennial oscillation is the stratosphere's Old Faithful. If Old Faithful stopped for a day, you'd begin to wonder about what was happening under the ground. It's really interesting when nature throws us a curveball.
NASA scientists are still unsure what exactly could have caused the anomaly. While NASA has been observing the same regular fluctuation in the wind patterns for six decades, that does not necessarily mean that this anomaly could not be part of some much longer cycle which has yet to repeat in the time data has been collected.
So far, the same usual suspects have been named as possible causes: an unusually strong El Niño, or climate change. As always though, more data will need to be collected before some unknown force can be ruled out.