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.
(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.)
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.
(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).
(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.
Hat tip to DT Lange
Hat tip to Colorado Bob
Hat tip to Sheri