Based on the spectacular data trove accessible to all, issued by NCEP-NCAR, I´ve been exercising a lot during the past years on the effects of climate change.
Though I haven´t done much this year, I took the opportunity for a snap moment to do some comparisons this morning.
First, the easy part, temp anomaly in what I call ´winter power´, a comparison of 45% of this years´ winter against the last three full winters (1 Oct / 31 Mar):
On the way to the top warmest Arctic winters in the satellite data era, although the Baffin Bay could present some surprises.
Then I watch 500Mb geopotential height. It always nicely reveals the planetary waves. Some years ago, I was looking for clues on the possible demise of the Ferrel (mid-latitude) cell and wave-supported transmission of heat to the Arctic.
Well, there’s something to see here, very steadfast ridging and troughing, underpinning why it is that warm around Eastern N America, Europe and Russia.
So I thought it might be interesting to compare the 500Mb situation for Oct and Nov to that during the last strong El Nino year, ’97:
That’s nice, you can see how the anomaly difference heaps up against the polar front in this global picture.
Maybe even clearer through focusing on the Poles:
In the North. PS December data show the ‘Greenland trough’ even more pronounced between N American and European ridges.
A little to my surprise (as the Antarctic usually shows opposing effects), the pattern is clear in the South, too:
And so, now it’s time to hold breath and wait for the end of winter to see if this lasts.
Given the strength of the pattern, I doubt very much this will flip over into widespread wintry weather anywhere on the Northern Hemisphere. Maybe a couple of weeks with snow over here in the Netherlands. Nothing remotely near getting my skates out of the storage.
To end this with a reminder quoted a lot some seasons ago; “the heat will come to haunt us”, I wish you all a good Christmas with your families and friends! Let’s enjoy what good is still around…