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Giant Gravity Waves Smashed Key Atmospheric Clock During Winter of 2016 — Possible Climate Change Link

Two [climate change] effects [of Arctic warming] are identified … : 1) weakened zonal winds, and 2) increased [Rossby] wave amplitude. These effects are particularly evident in autumn and winter consistent with sea-ice loss… Slower progression of upper-level waves would cause associated weather patterns in mid-latitudes to be more persistent, which may lead to an increased probability of extreme weather events — Evidence linking Arctic amplification to extreme weather in mid-latitudes, Dr. Jennifer Francis and Dr. Stephen Vavrus, Geophysical Research Letters (emphasis added)

The recent disruption in the quasi-biennial oscillation was not predicted, not even one month ahead. — Dr. Scott Osprey

This unexpected disruption to the climate system switches the cycling of the quasi-biennial oscillation forever. — Professor Adam Scaife

scientists believe that the quasi-biennial oscillation could become more susceptible to similar disruptions as the climate warms. — Physics.org (emphasis added)

jet-stream-crossing-equator-on-february-18-of-2016

(During February of 2016, high-amplitude Jet Stream waves or gravity waves interfered with the upper-level Equatorial Winds. This disruption was so significant that it caused a seasonal upper-level wind pattern near the Equator to change direction, a shift that was unprecedented in modern observation. Note how the upper-level wind flow frequently intersects with and even appears to cross the Equator at some points. Image source: Earth Nullschool global 250 hPa capture for February 18, 2016.)

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I’ve said it before, and I’m going to say it again — loss of predictable seasons, or seasonality, due to human-forced climate change is very big deal. And regardless of how all the scientific details specifically pan out, there are now observed changes to Northern Hemisphere winter, possibly due to human-forced warming, that are apparently starting to undermine its traditional seasonal climate behaviors. As a result, weather patterns appear to be shifting toward greater extremes and lower levels of predictability.

QBO — One of Our Most Predictable Atmospheric Clocks…

For decades now, scientists have been observing a kind of atmospheric clock tick-tocking high above the Equator. Up in the stratosphere, 10 to 13 kilometers above the Earth, winds tend to flow either east to west or west to east. These air flows change direction about every 28 to 29 months. This feature, called the quasi-biennial oscillation or QBO, has never significantly varied. It has always flowed in one direction for a predictable period of time and then switched to flow in the other direction.

Winds flowing at this level of the atmosphere over the Equator have a far-reaching effect, particularly on the winter climate of northern Europe. There, westerly high-level Equatorial winds are known to bring warmer, wetter winters. Easterlies in the stratosphere over the Equator are known to bring cooler, drier winters. The key to remember is that the QBO has always been both amazingly predictable itself, and had equally predictable climate effects. As a result, meteorological observation of the QBO natural-variability pattern enabled forecasters to get an idea of what weather trend to expect for winter — not just during a single year, but also over a longer time horizon.

…and Climate Change May Now Be in the Process of Breaking It

What happens if the QBO becomes less predictable due to influences such as human-forced polar warming? What happens if the big meanders in the Jet Stream produced by this warming dig down all the way to the Equator during Northern Hemisphere winters and start to shove at the upper-level Equatorial wind field, causing the QBO to switch? If that happens, then a major aspect of Northern Hemisphere winter seasonal variability will have been fundamentally altered by climate change. Winter would become less like it is now and more like some strange, difficult-to-predict, climate-change-morphed hybrid of a thing.

Over the past decade, scientists like Dr. Jennifer Francis have observed strange changes to the Northern Hemisphere Jet Stream. In winter, the North Pole has tended to exhibit extreme relative warming versus the rest of the Northern Hemisphere. This warming has created less difference in temperature from north to south during this season. As a result, it appears that the Jet Stream has slowed and is generating very large atmospheric waves, known as gravity waves or Rossby waves. At times, these waves have linked upper-level air flows between the Tropics and the North Pole.

(For years now, Dr. Jennifer Francis has warned that polar amplification could lead to some weird and extreme weather, especially during winter. However, no one initially predicted that the large Jet Stream waves apparently resulting from polar warming would completely disrupt the upper-level Equatorial winds as appears to have happened last February.)

Such strong polar warming during winter is called polar amplification, an effect produced by climate change. Polar amplification happens because greenhouse gasses resulting from fossil-fuel burning (like carbon dioxide and methane) preferentially trap heat during times of darkness. During December through March, large sections of the North Pole are blanketed in the dim of Polar Night. During this time the heat-trapping effects of these gasses really go to work. Additionally, heat from the ocean is transferred through the thinning veil of sea ice over the Arctic Ocean even as local carbon stores add to the overburden of the heat-trapping gasses already in place. The net effect is a much warmer-than-normal Arctic during winter. This warming appears to be doing a serious number on the Jet Stream and, apparently, even Equatorial atmospheric circulation.

Unprecedented QBO Switch in February 2016

During the most recent winter, scientists observed these high-amplitude Jet Stream waves reaching all the way into the Equatorial upper-level wind field with enough oomph to switch an east-west wind pattern to west-east. This switch was entirely unpredicted and unprecedented. No one expected it and it has never before been observed.

The weather pattern for a big swath of Europe was, as a result, flipped from the expected cool and dry to warm and wet. If you had told any atmospheric scientist that such a set of changes would happen, they might have categorically dismissed these claims. But now, some scientists are starting to look at the possibility that the recent QBO flip was due to a climate warming-related influence.

geographical-pattern-of-surface-warming

(Geographic pattern of surface warming as provided by the IPCC. Uneven relative warming of the surface of the Earth may result in some unexpected changes to larger atmospheric circulation patterns. Scientists now indicate that future flips in Equatorial wind patterns, like the big switch that occurred this past winter, may be driven by such atmospheric warming. Image source: IPCC.)

There is a possibility that the recent flip was related to large atmospheric waves which are potentially a result of polar amplification. These waves appear to have impacted the upper-level Equatorial winds, and so are not necessarily related to natural climate variability.

To initiate such a big atmospheric change requires a great deal of force. The equatorial wind field and atmospheric mass is generally the heaviest, is typically the region with the greatest atmospheric inertia. Having an outside influence, like polar warming and associated gravity waves, generating a flip in its flow is about the meteorological equivalent to rivers running up hill. Apparently, due to climate change, atmospheric ‘rivers’ in the Jet Stream may now be capable of doing just that, and that’s pretty disturbing.

Links/Statements/Hat tips:

Scientific hat tip to Dr. Jennifer Francis

Scientific hat tip to Dr. Scott Osprey

Scientific hat tip to Professor Adam Scaife

Evidence linking Arctic amplification to extreme weather in mid-latitudes

Unprecedented atmospheric behavior disrupts one of Earth’s most regular climate cycles

An unexpected disruption of the atmospheric quasi-biennial oscillation

Earth Nullschool

Note: Paul Beckwith again appears to be using this issue as a means self-promotion — bragging about ‘vindication’ and his video ‘that went viral.’ First, this issue is a matter of concern (not petty personal score-keeping). And it is probably one that remains uncertain given that the MET study is the first to touch on it in the peer reviewed science. So any definite claims at this point are both unwarranted and premature. Caution and humility should be the watch-words here. Not active grasping for credit or media attention. Further, I did not work with Paul Beckwith on his first ‘viral’ video — which was an independent response to my initial gravity waves article here. So responsible sources will not conflate my work with that of Paul’s even though he appears to agree with my (admittedly evolving) analysis in some (but not all) instances. For my part, this work is an attempt to open the issue. Not to close it or to support someone attempting to claim credit of first discovery.

Finally, I absolutely respect and admire the work and opinions of scientists like Gavin Schmidt, Stefan Rahmstorf, Jennifer Francis, the IPCC, the MET Office and others who have helped to build a powerful and compelling consensus on climate change as a critical issue for the 21st Century. Sometimes the process of threat identification will highlight instances that are outside of that consensus currently. And such identifications will, at times, result in strong reactions. I understand that this is part of the process and even if views differ, I will endeavor to read, and where I am able, incorporate them into my ongoing study here.

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Gigantic Gravity Waves to Mix Summer With Winter? Wrecked Jet Stream Now Runs From Pole-to-Pole

It’s as if global warming were ringing the Earth’s atmosphere like some great, cacophonous alarm bell. The upper level zonal winds are swinging wildly from record high positive anomalies to record low negative anomalies. Gravity waves — the kinds of big atmospheric waves that tend to move air from the Tropics all the way to the Poles and are powerful enough to cause the Caribbean Sea to ‘whistle’ in the satellite monitors — are growing larger. And the Jet Stream now has redefined all boundaries — flowing at times from the East Siberian Sea in the Arctic across the Equator and all the way south to West Antarctica.

Jet Stream Runs from Pole to Pole

(Northern Hemisphere Jet Stream runs from near 80 degrees North Latitude across the Equator in this Earth Nullschool screen capture to merge with the Southern Hemisphere Jet Stream and eventually reach West Antarctica. It’s the very picture of weather weirding due to climate change. Something that would not tend to happen under normal Holocene climate conditions. Something, that if it continues on a significant scale, may threaten seasonal integrity.)

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The big trough today begins near the Northern Hemisphere Pole. It pulls Arctic air down over Eastern Siberia and into a Pacific Ocean storm track. There, a second big dip in the Jet Stream pulls a crazy loop of this upper air flow further south. And here is where things get really weird — for the upper level river of air that began in the Arctic then makes a jump directly across the Equator.

But our story of a wayward Jet Stream doesn’t end there. The upper level air flow that originated near the North Pole joins with a building Southern Hemisphere Jet Stream ridge pattern over the Southeast Pacific. Feeding into very strong upper level winds, it turns southward into a high amplitude wave that crosses the Horn of South America and slams itself, carrying with it a big pulse of extreme warmth, into the upper level airs over Western Antarctica.

West Antarctic Heat

(An injection of hot, Summer air from the Northern Hemisphere into Southern Hemisphere Winter appears to have aided in the generation of 8 C above average temperatures over Western Antarctica during June of 2016. Image source: NOAA ESRL.)

A Climate Change-Driven Loss of Seasonal Integrity?

Like many extreme events resulting from human-forced climate change — this co-mingling of upper level airs from one Hemisphere with another is pretty strange. Historically, the Tropics — which produce the tallest and thickest air mass in the world — have served as a barrier to upper level winds moving from one Hemisphere to another. This barrier can tend to erode during seasonal flips. And so you sometimes get this mixing of sub-tropical Jet Stream winds over the Equator.

But as the Poles have warmed due to human-forced climate change, the Polar Jet Streams have moved out of the Middle Latitudes more and more. More and more they have invaded regions both within the Polar zone and within the Tropics — linking broadening Latitudinal zones. Now, it appears that the old dividing lines are weakening and that flows of upper level air between Hemispheres can be exchanged to a greater degree.

If this is the case, then it’s bad news for seasonality. Prevention and reduction of a mixing of air parcels between Hemispheres by the thick, hot tropical air mass is what has generated a strong division between Summer and Winter during the Holocene Climate Epoch. However, erode that boundary and you get more Summer heat spilling over into the Winter zone and vice versa. You get this weather-destabilizing and extreme weather generating mixing of seasons that is all part of a very difficult to deal with ‘Death of Winter’ type warming scenario.

In the very recent past, scientists favored a view that such a large-scale mixing between Hemispheres was not possible. But recent observations of Rossby Wave patterns seem to indicate instances where upper level air flows link Poles to Tropics and, in this case, where an upper level air pattern has linked Pole to Pole.

In addition, we have some rather weird behavior going on with the Equatorial zonal winds that may also be linked to climate change, but that currently remains a bit of a mystery. Sam Lillo and others have been tracking record variations in the Equatorial zonal wind pattern called Quasi Biennial Oscillation. And these variations may be linking up with the rest of the downstream climate system (Rossby-gravity waves etc).

QBO goes from record high to record low amplitude

(Upper level Equatorial zonal winds moved from record positive anomalies to record negative anomalies within a mere three month timeframe. Image source: Sam Lillo.)

All these observations combined highlight some serious concerns. Polar warming appears to be flattening the atmospheric slope from Equator to Pole to such an extent that an increasing violation of the Hemisphere to Hemisphere seasonal dividing line may be a new climate change related trend. And that’s a kind of weather weirding that we are not at all really prepared to deal with.

UPDATE — A Necessary Statement on the Accuracy of the Above Article and Related Edits

The original article prompted a reaction from a few atmospheric scientists (including noted climate skeptic Roy Spencer) as shown here in this Washington Post opinion piece by Jason Samenow, weather editor for the Post. In consideration of the information shared in this piece, I have made a couple of corrections to the information concerning upper-level equatorial wind patterns.

However, the inference taken from my article was somewhat misconstrued. Stating that a global climate emergency due to loss of seasonality is currently upon us and is far-reaching. The message in my article is that the situation appears to be worsening and that this particular global climate crisis may be something that we’ll face over the coming years and decades. The article was intended to highlight the risk posed by weakening dividing lines between climate zones, an apparent observed increase in meridional upper air patterns, and in this case, an observation of the upper-level wind pattern that crossed from pole to pole.

As I mentioned in my article, large meridional upper-level wind flows and related extreme weather, along with what appears to be a growing trend toward a loss of seasonality is a very big deal. Apparently not everyone agrees with me on this point. Regardless, the concern over loss of seasonal variation due to human-caused climate change remains an issue. While there is no guarantee that risk and climate meta-analysis will result in 100 percent accuracy, it is a worthwhile process nonetheless to both identify potential risks under the rapidly changing climate states of our world and to ask the hard questions.

In closing, I must gently disagree with the assertions Mr. Samenow put forth in his opinion piece. On the contrary, it is the height of responsibility to highlight issues that so many others have tended to ignore or discount at great risk to our global civilization.

Paul Beckwith has made his own statements in response to the above article. His statements and conclusions are his own.

If you do not listen to me, then please listen to what the Earth System is telling us. It is very, very concerning. Regards to all and best wishes.

–R

Links:

Earth Nullschool

NOAA ESRL

Sam Lillo

Something Absolutely Gigantic Appears to Be Whistling in the Caribbean Sea

Hat tip to DT Lange

Hat tip to Colorado Bob

Hat tip to Sheri

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