So much going on today I hardly know where to start. The warm anomaly over the Arctic Ocean that never goes away is certainly worth another update. It has become more and more clear to me that a large share of this anomaly is being caused by a lack of sea ice in places that most likely were fully iced over, at this time of year, during the 1979-2000 baseline period. There is more evidence behind this argument to look at, and some other things to think about too. We’ll start with an anomaly view from the Asian side:
The major anomaly in central Russia, a bit more than +20C, is certainly important but since there is no sea ice involved my comments will have to wait. I want first to focus on the Sea Ice map so we can match some things up with the equally large temperature anomaly directly above the Russian one:
Notice the broad stretch of open water north of Scandinavia. It is largely made up of three seas, Norwegian, Barents and Kara. If you match this entire unfrozen area with the anomaly map (it helps to magnify the images) you will see that the southern part of the ice-free area shows zero to fairly cool anomalies while most of the remainder to the north runs from +5 to at least +9. I don’t have any ice records handy but would wager that this northern part was pretty well iced up by early November in the past. My letter #1803 last Thursday dealt with a similar situation on the other side of the ocean, using a different approach, and saw the same type of effect. As a consequence, whenever we see an area of perhaps unusually ice-free water we should watch for a large amount of extra warming to appear, and any such warming effect must then be treated as something having its own separate source of attribution, even if the details are uncertain. Now we can open today’s Precipitable Water map:
What I see here does not look very helpful in the ice-free zone but the swirl of high vapor content moving over the ocean ice looks strong enough to do some real warming. All it takes at this time is 3-4kg to get the big anomaly readings we see. Now I want to point out something else. When you combine the warm anomalies attributed to open water with those attributed to inputs of overhead water vapor into a compact mass they may actually be feeding off of each other. They could do this by creating enough total warming to have a significant impact on the structure of air pressure configuration over the area being warmed. Remember how warm air always expands, causing an upward push against the downward pressures of gravity created by the air higher up. Take a look at this map:
Notice the small circular spot right in the middle of the blue zone. I don’t think it would be there if the air below it were as cold as normal. More broadly, large warm anomalies elsewhere are eating away at the outer edges of the blue zone, causing those big lobe-shaped appearances to form. The result, both inside and out, governs the positioning and strength of jetstream winds, the very same winds that exercise so much day-by-day control over the movement of high-altitude vapor streams. And they are losing some of the control they would normally have. Today’s vapor streams are massive, especially in the Northern Hemisphere, and their vapor content is gaining a growing amount of access to various parts of the far north. In this final map we can see a jetstream wind that has visibly guided the flow of a vapor stream in an arc across Europe (as seen on the PWat map), then made turns that ended with a dumping off of its contents into the area of central Russia now having the +20 anomaly.
Carl