Tuesday, 26 January 2016

Robertscribbler on the cold snap in Asia

Arctic Heatwave Drives Deadly Asian Cold Snap

25 January, 2016
In the Arctic today, there’s a warm wind howling over Siberia. It’s a wind blowing from the northwest. A wind originating from the Arctic Ocean. Siberia is warming up today because warm air blew in from the direction of the North Pole. This should strike everyone as ridiculously, insanely odd.
In Okinawa it snowed for the first time on record this weekend. In Taiwan, a cold snap turned deadly killing 85 as tens of thousands more huddled in homes that lacked any form of central heating. In South Korea, 500 flights were grounded due to unseasonable weather. In Hong Kong, the temperature was 3 C — the same temperature as a region near the southwestern coast of Svalbard east of Greenland and above the Arctic Circle.

What the hell is going on? In short, a global warming driven heat-up of the Arctic has punched a hole in the Jet Stream and driven chill, Arctic air all the way into portions of Southeast Asia that seldom ever see temperatures go below 60 degrees Fahrenheit (16 Celsius).
An Arctic Super-Warmed By Climate Change

Temperatures in the Arctic are just off the charts warm for this time of year. It’s the sad result for a region that now sits in the bull’s eye of rapid heat accumulation due to human greenhouse gas emissions forcing the world above 400 parts per million CO2 and 485 parts per million CO2e. CO2 levels alone that have not been seen in at least 3 million years and a ridiculous total heat forcing at the top of the atmosphere that likely hasn’t been seen for all of the past 10 million years.

Arctic Heatwave, Southeast Asian Chill
(Extreme heat in the High Arctic brings summer-like seasonality to that region even as a record cold snap grips sections of Southeast Asia. Image source: Climate Reanalyzer.)

It’s the kind of heat forcing that has a profound, far-ranging impacts. Impacts, that for many regions of our world, start in the Arctic.
There, in the long dark of polar night, all that overburden of greenhouse gasses is doing its work to re-radiate the sun’s heat. And the ocean sitting beneath the inexorably thinning and greatly reduced sea ice is also transporting that accumulated heat into the Arctic air. Firing off weather systems that run northward in Kamikaze fashion. Surging up through the gauntlet of Greenland chill along that increasingly dangerous storm bombification zone of the North Atlantic. Howling over Svalbard and into the Arctic itself. Giant heat engines aimed directly at the Arctic’s heart.
And heat the Arctic in strange and stunning fashion all of these various processes do — with a large region of extreme, above average temperatures stretching from the North Pole itself, to the northeast tip of Greenland, all throughout a quarter-pie section of the High Arctic above the 80th parallel, on into the Kara, the Laptev, and finally terminating in what should be deeply frozen North-Central Siberia. This entire vast region features temperatures in the range of 20 degrees Celsius or more (36 degrees Fahrenheit) above average for this time of year. For today, for this vast section of the Arctic, it’s as if the Winter Season did not exist.
Extreme Warmth in the Arctic, Cold in Southeast Asia

(Gale force northwesterly winds bring much warmer than usual temperatures to Northeastern Siberia even as record cold hits Southeast Asia. Image source: Earth Nullschool.)

Just off the coast of Svalbard the current temperature is 3.7 C (or 39 degrees F). That’s the same reading that Taipei City Taiwan, thousands of miles to the south and sitting in the ridiculously warm Southwest Pacific, saw yesterday. Running along the zero degree Longitude line to 85 North, just a few hundred miles from the North Pole, we find 1 C or 34 F temperatures. Temperatures run near or even above freezing along a vast section of ice-covered waters in the Arctic Ocean above 80 North Latitude and on toward the coast of Siberia. There at 74.5 North and 87.55 East, a freakishly warm northwest wind howling out of the Arctic Ocean is pushing temperatures to -1.4 C (29.5 F and above the point at which salty ocean water freezes). It’s colder now in the hills of North Vietnam at 20.1 North Latitude, 103.9 East Longitude with temperatures there hitting -1.5 C (29.3 F).
This is worth repeating — it’s colder in North Vietnam than it is on the shores of Arctic Siberia. Something, most definitely is not right with the weather.
Predictable Seasons Disrupted

To understand what, we need to think for a little bit about atmospheric physics. In a normal world — meaning the world in which we’re used to living, the same world in which human civilization developed and evolved — cold remains mostly locked in the Arctic. Heat remains most highly concentrated at the Equator. This is due to the fact that at the greenhouse gas levels of the Holocene (in the range of 275 parts per million CO2 and 600 parts per billion methane) solar insolation — or the direct heating of the Earth’s surface by the sun’s rays — was more-so in the driver’s seat. The blanket of greenhouse gasses was in that nice Goldilocks zone where its heat trapping ability was just enough to keep the Equator hot, the mid Latitudes mostly warm, and the poles cold. Just right.
This just right atmospheric heat balance with cold at the poles and heat at the Equator set up a large temperature difference between the low Latitudes and the Poles. This high degree of thermal difference, in turn, drove strong circumpolar winds called the Jet Stream that mostly kept the climate zones stable and locked in place. In the north, it was cold, as it should be. And, in the south, it was hot, as it should be. That rapidly moving wall of upper level air did its part to keep the climates divided and stable. To keep the seasons we now know in their appropriate phases and predictable progressions — Winter, Spring, Summer, and Fall (please see Dr Jennifer Francis — Jet Stream and Climate Change).

But now, with greenhouse gasses rocketing to above 400 parts per million CO2 and above 1830 parts per million methane, the Goldilocks zone for human climate is no more. Now, the purity of polar cold has been violated by floods of heat rushing up from the south and oozing up through the ocean itself. Now, that kind regulator of the seasons — the Jet Stream — has been driven into a helter-skelter tangle. And this is why it’s warmer in the Arctic than it is in parts of Southeast Asia.
Arctic Heat Drives Asia Chill

Polar Vortex Disrupted
(Warm air injected into the Arctic through a weakness in the Jet Stream over the North Atlantic drives a polar vortex disruption, strong trough formation over Eastern Siberia and a record Asian cold snap. Image source: University of Washington Jet Stream Analysis)

And it’s exactly the kind of scenario that happened this weekend through today. A weakness in the Jet Stream just west of the United Kingdom developed — allowing warm air to flood northward into the Arctic. While the UK and sections of the Arctic began to experience warm temperatures more usual for Spring and Summer in the affected regions, polar cold was driven southward — this time down another weakness in the Jet Stream that developed over Siberia through Southeast Asia.
It’s the kind of polar vortex disruption, distortion and collapse that we’ve seen so much of during recent Winters. A pattern of warm north, cold south that is the very upshot of a rapidly warming world and an equally swiftly destabilizing climate system.
Hat Tip to Greg
Hat Tip to DT Lange
Hat Tip to Ryan in New England

No comments:

Post a Comment