Saturday, January 12, 2013

Polar Vortex Collapsing; Complete Disintegration Possible

The polar vortex has begun the intense and dramatic process of its collapse, as shown in the above multi-panel image from the Japan Meteorological Agency (JMA). In the image, we see a 6-day chart of observed heights at the 30 millibar level in the stratosphere, typically known as the mid-upper stratosphere. You can clearly see the separation of the polar vortex into two daughter vortices, with one over Eurasia and another over Canada. The dominant vortice in this case is the Eurasian one, due to its massive size, but the Canadian vortice appears to be a small, compact daughter vortex, not unlike Hurricane Andrew in 1992. I'm certainly not saying that these vortices are producing effects like that of Andrew, the stratosphere is not capable of such a feat. However, the split tells us forecasters 'The Arctic is having a breakdown.'

This split was caused by the much-anticipated Second Warming that I have been posting about for days on end. This second warming is the second 'C' in my new 'Three C's' List, which consists of the following:

-Corrosion
-Crack (Split)
-Collapse

The Corrosion refers to the weakening of the polar vortex to a point of a state that it has not collapsed, but has sustained damage to the point that a split is possible. The Crack refers to the split in the polar vortex, when a stratospheric warming forces the vortex to crack into several vortices. And finally, the Collapse indicates the polar vortex can no longer control the Arctic, and its vortices are forced south into lower latitudes. I believe we are well on our way to the last stage of Collapse, shown by the chart below:

This is an image of potential vorticity values for the Day 10 forecast from the ECMWF model. Higher potential vorticity values indicate the presence of low pressure, in this case the polar vortex. The number 850 K on the above image refers to the isentropic level of 850 K. Before you start wondering what all this means, let's sort it out. The isentropic level 850 K is equivalent to 15 millibars, meaning this is a forecast for the strength of the polar vortex in the relative upper stratosphere at 15 millibars. Not to hard to understand now, is it? Anyhow, do you see any oranges or even whites? No? That means THERE IS NO POLAR VORTEX. It's GONE. It has actually gone beyond Collapse into a whole new level of disintegration.

We just want this disintegration to propagate down to the lower stratosphere, like the level 475 K shown below (roughly 105 millibars, the very bottom of the stratosphere):

Things are still looking very good for the end of January into February. Maybe a little toned down on the cold for late January, but Siberia supports a very chilly February.

Andrew

1 comment:

Babsie said...

Siberia supports a very chilly February? Those poor people, I know they're used to be, but it's already been -60F. Some of the traffic lights in Yakutsk stopped working a few days ago.