Winter solstice

Today is the winter solstice. If you live on the Northern Hemisphere of our planet Earth, today is the shortest day of the year. In a sense it's the start of the countdown towards a new melting season, with the Sun slowly creeping northward a bit every day, although the sea ice still has a couple of months to expand and thicken some more, of course.

Most of you who are interested in the Arctic, probably know that during the 2015 AGU Fall Meeting NOAA put out its annual Arctic Report Card. The report contains a lot of details on everything concerning the Arctic in 2015, and that mostly means melting. Melting sea ice, melting glaciers, snow cover loss, etc., and the consequences thereof.

There's a very good article by Yereth Rosen on the ADN Arctic Newswire website, and Robertscribbler also put a blog post up today, but if you want a quick, visual summary, there's this video that NOAA put out last week:

Some other news concerning the Arctic that received traction in the media lately, is this new paper by Yeager et al. that was published in Geophysical Research Letters two weeks ago. Its title Predicted slowdown in the rate of Atlantic sea ice loss lacks the nuance that what is actually meant is winter sea ice loss, but it's explained in the rest of the text. Strangely enough, a paper by the same authors also appeared on the Nature website last week in which the nuance is omitted entirely, in both title (Possible pause in Arctic sea-ice loss) and text. Then again, the rest of the text is behind a pay-wall (edit: never mind, I have been informed that it's just a reference to the GRL paper, not a paper in itself).

Either way, the theory is that a weakened Atlantic Meridional Overturning Circulation (AMOC) will prevent warm Atlantic waters from going deep into the Arctic, and thus in winter sea ice will expand. See this informative Science Codex article for further details and quotes from the paper's researchers, such as this one:

"We know that over the long term, winter sea ice will continue to retreat," said NCAR scientist Stephen Yeager, lead author of the study published online today in the journal Geophysical Research Letters. "But we are predicting that the rate will taper off for several years in the future before resuming. We are not implying some kind of recovery from the effects of human-caused global warming; it's really just a slow down in winter sea ice loss."

It makes sense, of course, as ocean heat flux has probably played a big role in Arctic sea ice loss so far. And it seems less heat is being transported into the Arctic from the Atlantic side, as this image from a Diablobanquisa blog post back in October shows:

Image taken from this presentation at the ASOF II (Arctic Subarctic Ocean Fluxes) Congress in Bremerhaven back in March

Except for the AMOC and AMO (Atlantic Multidecadal Oscillation), I can't think of any other factors or negative feedbacks that could put Arctic sea ice loss on hold for a prolonged period of time. That doesn't mean there isn't one, I just can't think of any. And according to research, not even the AMO has as much of an influence on Arctic sea ice loss as AGW has. But it will be interesting to see whether Yeager's prediction that a weak AMOC will keep winter sea ice loss more or less stable in the foreseeable future, will turn out to be correct, and if this will influence summer sea ice loss as well.

Finally, some other stuff I haven't had the time to highlight, is this citizen science project, as explained in this UW (University of Washington) Today article:

Citizen-science climate project adds logs from historic Arctic whaling ships

Even if climate negotiations in Paris are successful, the planet is locked into long-term warming and an uncertain future. The Arctic is warming twice as fast as the rest of the world.

A January 1870 page from the log of the Trident, a whaling vessel that sailed out of New Bedford, Massachusetts. Volunteers transcribe the handwritten text for climate clues. New Bedford Whaling Museum

But what was the Arctic like before — when maritime explorers and whale hunters first ventured into its icy seas? If scientists could know more about Arctic climate of the past, they could better understand today’s changes, and use that knowledge to improve projections for the future.

Old Weather is a citizen-science project led by a University of Washington scientist and former mariner that is mining historic ships logs to get a unique peek at Arctic climate over the past two centuries.

An update launched Dec. 3 expands the project to also include hundreds of whaling ships, whose logbooks were preserved and scanned into digital form from New England museums and libraries.

(...)

“They’re not doing the hourly instrumental weather that the federal ships did, but they talk about sea ice in a very thorough way,” Wood said. “We can get more than one ship at a time in one area. This will allow us to get a much better characterization of the sea ice and other environmental conditions, especially in the Pacific Arctic.”

I think it's really cool that volunteers donate time to help get a clearer picture of sea ice conditions from the mid-1800s to the early 1900s. It seems anyone can get involved, so if you have time on your hands...

That's it for now. I wish you all a happy and peaceful time during Christmas, in which we (more or less consciously) celebrate the winter solstice and start longing for the return of Proserpina. And then 2016 will be upon us, a new year with a new melting season.

Comments

[Nick Stokes]

"I wish you all a happy and peaceful time during Christmas, in which we (more or less consciously) celebrate the winter solstice"

Thanks, and to you too. This is how we celebrate here:

https://media.apnarm.net.au/img/media/images/2015/11/26/SNN_27-11-2015_NEWS_13_SNN271115%20santaonthebeach_fct676x507x281.0_ct620x465.jpg

[Zaphrail]

If that idea is correct the heat will go the other way, probably somewhere just south of the Arctic, east and west of the Atlantic ocean

[Colorado Bob]

This detail from the Arctic Report Card caught my eye.

Green tundra is turning brown as Arctic warms

And in another sign of change, 2014 and the first seven months of 2015 saw the combined discharge of fresh water from eight Eurasian and North American rivers into the Arctic Ocean rise by 10% above the level from 1980 to 1989. Scientists attribute the rise to increasing precipitation linked to global warming.

http://www.climatechangenews.com/2015/12/21/green-tundra-turning-brown-as-arctic-warms/

[John Christensen]

Great entry - Happy Holidays to you as well Neven!

[wayne]

Neven , I think our work is never finished, as soon as we rest during the festive season, the
met TV presenters get to blame these days of huge world wide record shattering temperature records on El-Nino. They certainly don't know what they are talking about, and so mislead the larger population as usual, creating the right kind of background for any misinformer to have fun with their adventures of muddling reality.

http://eh2r.blogspot.ca/2015/12/record-shattering-solstice-temperatures.html

Happy NEW YEAR guys, it is the true new year at solstice.

Merry Christmas (although should be during the usual Roman Empire census in March!) :)

[Pete Williamson]

Nick Stokes, @17oC it's almost like an aussie Christmas here in Quebec, highly unusual.

"Except for the AMOC and AMO (Atlantic Multidecadal Oscillation), I can't think of any other factors or negative feedbacks that could put Arctic sea ice loss on hold for a prolonged period of time."

I'll take up the challenge. One possibility might be atmospheric circulation changes over the Arctic. I know I've pushed this paper before but it does highlight the possibility that atmospheric circulation since around 2000 have generally favoured ice loss and that this is unusual within the longer term reconstruction. It does seem plausible that a return to more 'normal' or even low export conditions (both have existed for extended periods in the past) could add to add to any AMOC effect. Of course whether that comes about is uncertain given the competing attribution to the changes but it seems like a possibility.

http://orbi.ulg.be/handle/2268/175926

Neven, thanks for continuing to present interesting and challenging ideas in your blog.

[D]

Merry Christmas from the Fish.

The increasing salinity, but cool potential temperatures of water recently entering the Arctic shows that more cold air has been advected over it, not a slow down in the AMOC.

The NAO and the AMOC was very strong form 1988 to 1995 relative to the periods before and after according to a number of peer reviewed publications. There is a lag between maximum AMOC and heat in the north Atlantic, so the high positive NAO led to the influx of heat into the Arctic in the following decade.

At present there is a large negative anomaly in sea surface heights in the subpolar gyre in the north Atlantic and subarctic seas. Last winters very cold temperatures and strong storms from January through March apparently cooled the salty water and it became dense. It looks like the overturning circulation is still pretty strong.

I think that the modellers need to take into account what's going on around Antarctica. That's where the big slowdown in overturning has happened because of winds tightening around Antarctica and the development of a surface fresh water layer that is stabilizing the water column.

[Susan Anderson]

Thanks fish, that's something I wanted to know about.

Seasonal warmth to all.

[Anna May]

Only tangentially related to this post, but what do folks here make of the blog post below? Is this storm "freak weather" or does this have long-term climate implications? Also, what does the extreme temperature anomaly imply for next year's melt season?

http://robertscribbler.com/2015/12/27/warm-arctic-storm-to-hurl-hurricane-force-winds-at-uk-and-iceland-push-temps-to-72-degrees-f-above-normal-at-north-pole/

[Werther]

Good afternoon Anna,
I read that entry too this morning. Several friends on the Forum noticed it a couple of days ago. JDAllen first, I guess, on the ‘Weird weather’- thread.
Yesterday I placed this overview in the ‘Freezing season’-thread. It shows the planetary (Rossby)waves circling the Pole:

After a two month siege a lot of (sub-)tropical heat makes its way up North, in a ridge of exceptional proportions. This heat manifested itself first over SE United States. A lot of it is transmitted to the Arctic on the head of this wave.

It might even propagate into the Stratosphere, giving birth to the first Sudden Stratospheric Warming event for this winter.
There have been some large ridge-incursions during the last few years. In their strength and amplitude, they illustrate the changes that are well underway in the atmosphere. In that sense, I fully agree with RobertS.

For its direct effect on this freezing season, it doesn’t seem likely that it will be noticeable over the whole run. The temp anomaly for the Arctic is already there; continued advection of warmth seems relentless. This is just one interesting event.

The biggest effect this event has is on weather. As the Arctic Oscillation (AO) is heading for negative, soon a wave of cold will be pushed out into the mid-latitudes. I didn’t foresee that, maybe I can retrieve my skates from the storage after all…

[Neven]

Only tangentially related to this post, but what do folks here make of the blog post below? Is this storm "freak weather" or does this have long-term climate implications? Also, what does the extreme temperature anomaly imply for next year's melt season?

It's a great and very interesting blog post. Iceland saw a very big storm just a few weeks ago, and now another one. We also saw an ongoing train of cyclones being pushed from the Atlantic into the Arctic during the 2014/2015 freezing season. But that was during the second part of the freezing season, from January onwards.

It will be interesting to see what happens next, and how that will impact the initial state of the sea ice.

Here we see the sliver of almost zero degree temperature reaching towards the NP:

As the Arctic Oscillation (AO) is heading for negative, soon a wave of cold will be pushed out into the mid-latitudes.

Indeed, Werther (hadn't seen that yet). Should be better for the sea ice overall.

[TenneyNaumer]

Colorado Bob, I noticed browning near the shore along Siberia and wondered if it had to do with salt water intrusion into the thawing permafrost or if it had anything to do with excess methane being emitted from the warmer permafrost.

[TenneyNaumer]

At the moment, it doesn't appear that the cold blob in the North Atlantic is keeping warmer air out.

[John Christensen]

I agree with you Neven that spreading the cold with the negative AO should help ice formation in the peripheral seas and with the jet stream moving further south, less humidity should reach the central Arctic Ocean.

However, it will be interesting if the current low near the Pole will have any impact. Ice thickness could actually increase in spite of the relative high temperatures due to increased ice compaction and secondly there should be substantial precipitation, which may help reducing exposure of the ice when we get to the spring.

[D]

Fish again. It isn't warming 72ºF at the pole. Maybe 50F. The map Robert used is based on an average temp for the pole that's not correct. DWI shows 80ºN to the pole temps have been near average.

As Werther wrote, the big effect of the warm up in the Arctic will be change in the weather with the AO flip. Europe and the eastern U.S. will see normal to below normal temperatures soon.

On a longer term basis there has been a consistent push of warmer water up the coast of Norway into the Barents sea. The weather patterns will continue to support much warmer than normal water in the Barents and flowing into the Arctic from the Atlantic side. This warm water could have an effect on sea ice on the European side of the Arctic next summer.

[jdallen_wa]

Ice thickness could actually increase in spite of the relative high temperatures due to increased ice compaction and secondly there should be substantial precipitation, which may help reducing exposure of the ice when we get to the spring.

This sounds like a bit of hopeful thinking, I'm afraid. I don't think a few days of compaction will make up for the heat getting retained. I think the precipitation will similarly have a slightly negative or zero sum effect on refreezing.

It isn't warming 72ºF at the pole. Maybe 50F. The map Robert used is based on an average temp for the pole that's not correct. DWI shows 80ºN to the pole temps have been near average.

Univ. of Maine (climate reanalyzer) is off by 20F? Seems like they've been pretty good, and more sites than just they have predicted temperatures near or slightly above zero at the pole. If I understand correctly, that is a 70F departure from the expected usual -40C/40F.

But, nonetheless, a 50F rather than 70F anomaly here in Seattle would mean we'd only hit 95F instead of 115.

Only 50F anomaly at the pole. In mid-winter. It's still shocking. And its probably higher than that.

I am hopeful that an AO flip will change the pattern, but pessimistic that it will significantly improve the refreeze.

[Werther]

A temporary AO flip, as a side effect while a SSW occurs, won't create a strong 'winterpower' effect.
A SSW will propagate back into the Arctic troposphere, driving up lower trop temps with a time lag of one or two weeks.
Considering the whole set-up, I don't see much in support of strong volume growth at all.

Positive AO and a strong Polar Vortex would be great. But the Vortex is besieged by warnth advection originating from the Hadley Cell. In that sense, the Ferrel Cell is already becoming overrun (hope that is correct use of the English language).

[Neven]

Hopefully the cold can stay out of Europe for a while longer, because tomorrow I'll be crossing a large part of it, and back next week. I'm always nervous when driving through snow, especially if there's a wife, kid and dog with me in the car.

[VaughnA]

Wishing everyone the best for the new year.

Interestingly Weather Underground shows an active wildfire for December 31 near Peace River in northern Canada. Seems pretty unusual for a wildfire in that area this time of year.

http://www.wunderground.com/