« EGU2016, my impressions | Main | PIOMAS May 2016 »

Comments

Feed You can follow this conversation by subscribing to the comment feed for this post.

DavidR

Temperatures so far this year have been off the scale as shown in this post.

http://forum.arctic-sea-ice.net/index.php?action=post;quote=76486;topic=1538.0;last_msg=76486

Globally and in the Arctic 67N+, and 80N+, temperatures have been more than three std devs above average, with previous records only 2 std deviations above average.

As Dorothy said in the Wizard of Oz, we're not in Kansas anymore.

John Christensen

Kevin said:

John Christensen: You have made the same mistake that many others have made. Neither Maslowski's original AGU presentation nor the radio interview you pointed to support your claim that he originally said 2013 and then modified it.


OK, then check this compilation on Dr Maslowski projections:

May 2006:

American Meteorological Society seminar, appears not to be from a presentation, but has been quoted by Joe Romm:

http://thinkprogress.org/climate/2010/06/06/206155/arctic-death-spiral-maslowski-ice-free-arctic-watts-goddard-wattsupwiththat/

“If this trend persists for another 10 years-and it has through 2005-we could be ice free in the summer.”

October 2007:

http://www.nytimes.com/2007/10/02/science/earth/02arct.html?_r=0

“Experts say the ice retreat is likely to be even bigger next summer because this winter’s freeze is starting from such a huge ice deficit. At least one researcher, Wieslaw Maslowski of the Naval Postgraduate School in Monterey, Calif., projects a blue Arctic Ocean in summers by 2013.”

December 2007:

Australian ABC:

http://www.abc.net.au/am/content/2007/s2117573.htm

“A US-based team has told a conference in California that the northern polar waters could be ice-free in summer by 2013.

Professor Wieslaw Maslowski from the Naval Postgraduate School in Monterey, California, has been presenting his work to a meeting of the American Geophysical Union.”

December 2007:

Beyond Zero Emissions, Dr Wieslaw Maslowski predicted a 2013 Ice Free Summer Arctic five years ago - now he says that may have been too conservative, Radio Interview, Australia:

http://bze.org.au/media/radio/dr-wieslaw-maslowski-predicted-2013-ice-free-summer-arctic-five-years-ago-now-he-says-ma

“We speak to Wieslaw Maslowski about his prediction that by the summer of 2013, we will have completely lost ice cover in the Arctic. Dr. Maslowski says that the complete loss of summer ice may actually happen sooner.”

HOST: As reported in the NY Times that you said that 2013 was a possibility and perhaps you had actually projected this some years ago, that we could lose the summer sea ice extent, that is in the summer solstice, correct?

MASLOWSKI: That is correct.
So the minimum in the Arctic sea ice extent has been typically occurring sometime in September, between early September and late September every summer, so the minimum of ice extent has been defined as the ice edge of say 15-20% ice cover and then everything inside this ice-edge position is considered to be the ice extent.
.. And our studies are suggesting that actually the volume and the thickness is decreasing even faster than the areal observations from satellites. And this way we are saying that actually if we already have lost probably 40% of the volume in the Arctic so far, if we project this trend ongoing from the last 10-15 years, we probably will hit zero sometime in the summer mid-next century, mid-next decade, I’m sorry.

HOST: Sorry, there has been other projections from some glaciologists from around the 2020, so somewhere around the range, you said 2013 in NY Times, where it was reported?

MASLOWSKI: That is correct.
..
My statement on the, that you quoted on the, that was printed in NY Times of 2013, my first prediction where I actually had this projection stated explicitly was about 4-5 years ago in San Francisco in the AGU Fall Meeting, so I am actually not upgrading my projection – I’m just saying it might happen sooner, but we were one of the early people, who were saying it might happen within the next decade instead of the end of this century.“

October 2009:

“Toward Advanced Understanding and Prediction of Arctic Climate Change”
34th Annual Climate Diagnostics and Prediction Workshop, Monterey, CA, 26-30 October, 2009

http://met.nps.edu/climate_CDPW09/documents/Session_2/2.11_Maslowski_34th_CDPW_Oct009.ppt

On slide 11 Dr Maslowski is reviewing trends on Arctic ice volume decline observed and notes:

“If this trend persists the Arctic Ocean will become ice-free by ~2013!”

March 2010:

State of the Arctic Meeting:
On slide 12 Dr Maslowski is reviewing trends on Arctic sea ice volume and notes:

“Combined (95-07) model / data linear volume trend of -1075 km3/yrprojects ice-free fall by 2016 (3yrs uncertainty -95-07)”

April 2011:

New warning on Arctic sea ice melt, BBC, 8 April 2011

http://www.bbc.com/news/science-environment-13002706

“Scientists who predicted a few years ago that Arctic summers could be ice-free by 2013 now say summer sea ice will probably be gone in this decade.
The original prediction, made in 2007, gained Wieslaw Maslowski's team a deal of criticism from some of their peers.
Now they are working with a new computer model - compiled partly in response to those criticisms - that produces a "best guess" date of 2016.
Their work was unveiled at the European Geosciences Union (EGU) annual meeting.
"In the past... we were just extrapolating into the future assuming that trends might persist as we've seen in recent times," said Dr Maslowski,
"Now we're trying to be more systematic, and we've developed a regional Arctic climate model that's very similar to the global climate models participating in Intergovernmental Panel on Climate Change (IPCC) assessments," he told BBC News.
And one of the projections it comes out with is that the summer melt could lead to ice-free Arctic seas by 2016 - "plus or minus three years".
..
Inclusion of this data into the team's modelling was one of the factors causing them to retrench on the 2013 date, which raised eyebrows - and subsequently some criticism - when it emerged at a US science meeting four years ago.


What you see from this thread, Kevin, is that Dr. Maslowski has refined his predictions along with the progress of his work and models, which all seems quite reasonable.

John Christensen

And interestingly, Dr. Maslowski mentioned in the interview of Dec. 2007 that his original prediction is from the AGU Fall Meeting 4-5 years earlier, meaning that his prediction originally was from 2002 or 2003.

Chris Reynolds

Bobcobb,

You asked for my opinion on Rignot/Hansen. The way I read that Washington Post article is as follows:

1) A Journalist for a paper like the Washington Post can be expected not to put words in people's mouths, this cannot be said of the gutter press, but papers like The Times and Washington Post have a reputation that is a financial asset and is not taken lightly (My company's similar - I am prepared to sack people on the spot for things like falsifying results). The journalist states that "as a co-author, he contributed some insights to Hansen’s paper" I'd take this as a correct summary of what Rignot said. Therefore people countering you by claiming that as a co-author Rignot backs Hansen 2015 to the hilt are wrong. Hansen credited Rignot as he offered insights, not because he is fully behind the paper's conclusions.

2) Rignot cites the caveat that there may be limits to speed of loss of glaciers. This does not mean he is so open minded his brains will fall out.

3) Rignot thinks scientists should not have private and public opinions for fear of attack or ridicule (he calls those who moderate away from their private thoughts 'chicken'. His response to the Hansen paper was one of approval: "Jim Hansen really stirred the pot this week.", the facial expression one would normally associate with that statement is a smile and a general tone that 'stirring the pot' is rather a good thing, even if one doesn't engage in it oneself.

4) Rignot seems to be concerned with trying "to come up with ways we can put upper bounds on these changes". This might explain his approval of Hansen, he may see the Hansen paper as a useful addition to the upper bounding effort.

My opinion is what you asked for: I wasn't persuaded by the Hansen paper, and still think that as of about 1/6 of the way into this century 2100 SLR is likely to be of the order of 1 to 1.5m worst case (all the favourable variables turned to maximum). But I don't think you're justified in saying 'highly questionable'. That term holds a perjorative context in the English langauge, there is a difference between me telling someone their findings are 'possibly in error' (polite), and 'highly questionable' (blunt on the verge of being rather rude). I think Rignot falls in former not the latter camp with regards his opinion on the Hansen paper.

BTW. I am sceptical about the prospects for beating 2012 this year purely because summer weather can screw up a head start. That noted I do think it's the most promising year for an exciting melt season we've had for years.

Chris Reynolds

Rob Dekker, David R,

Arctic Dipole...

My point is that the factors of snowline retreat and albedo are popular, but they are not the only players. That is not to say that they are not signficant in preconditioning for the melt season, they are. However remember 2013? That wasn't just a lack of the atmospheric pattern that gives rise to the summer Arctic Dipole Anomaly it was a reversal of the pattern and that got us to a boring summer on the ice and a poor perfomance of the summer minimum (high for the post 2007 period).

Blaine has pointed out on this blog that the Arctic Dipole may be driven by anomalous retreat of the ice edge off Siberia, this fits with research. And at present (30 April data) PIOMAS ice condition is healthy off the Siberian coast.

I have spent years studying the AD phenomenon and have yet to find a precursor pattern that allows me to predict AD activity in the summer from a lead time in May. Despite all I have read I remain totally unsure of what the weird winter weather will transate into in the summer and how this may impact the chances of strong AD activity this summer. The factors driving the weird winter may enhance the chances of an AD persistence this year. I have said before that were we to see the sort of AD strength seen last July all June and July then we could see 2012 smashed. However equally we have yet to see a very strong early preconditioning of the ice pack stymied by the lack of an AD during the summer, that we have not seen this may be a result of the small set of years post 2007 rather than that it is impossible.

I'm seeing a strong correlation between those who still subscribe to the fast crash position and those who this time most years cry imminent record. I just thing both positions do not necessarily carry the strength of evidence a casual observer might consider the stridency of their adherents implies.

Chris Reynolds

Rob, Kevin,

My opinion has changed radically since I wrote 'Go On Say Something Outrageous'. The understanding I lacked when writing that post also casts light on the graph of extent and volume that I did and fitted a power function to.
http://2.bp.blogspot.com/-TA4qFR0WL1A/Uy3G1FUQS6I/AAAAAAAAAPU/VSrpuRhbE-Q/s1600/Extent+&+Vol.png

That graph does not suggest an imminent collapse at all because it conveys no information about speed of progression along the power function trend. The thickness growth feedback seems to me to be in the process of slowing progress along the line, especially as most progress in the past has been from loss of thick multi-year ice volume.
http://2.bp.blogspot.com/-4_d4NG-fsQs/VWa2V86BV7I/AAAAAAAAB_c/zNEWil9jHVA/s1600/PIOMAS%2BGice%2BApril%2BBands.png

The fact that in PIOMAS thin young ice has not declined as has the thick multi-year ice supports the interpretation of an ongoing inflection in volume loss.
http://1.bp.blogspot.com/-GAv0JbajhaE/VWbBQ-NAnxI/AAAAAAAAB_s/n-2eI7ScHGs/s1600/Arrctic%2BOcean%2BWall.png
As overall decline hits that wall so the decline of volume rate reduces and the decline assumes a new regime of decline in line with the winter warming of the Arctic reducing winter ice growth.

And on that subject, as for this winter, if anyone suspects it may be a new regime that would be a strong argument for a fast crash. However absent strong evidence of such a new regime, I'll need at least three winters such as the one just gone to seriously consider a new regime.

Tony

Chris Reynolds, interesting perspective. However, I think that even the weaker "possibly in error" is difficult to justify from the articles linked to by bobcobb.

Artful Dodger

Voyageur | May 13, 2016 at 13:35 asked

"could the wave action from the usual series of storms be sufficient to destroy the fresh-water lens over a single season if the CAB was essentially ice free some September?"

Yes, wave mixing is one way a storm could break up the surface layer, along with Ekman pumping.

Indeed, other means to remove Arctic sea ice were proposed by Soviet scientists back in the 1950s and '60s:

The Soviet Scientist Who Dreamed of Melting the Arctic with a 55 Mile Dam

Another Arctic geoengining proposal at the time was to divert North flowing Siberian rivers to the South. Scientists recognized that the resulting change in Arctic basin surface sality might remove the sea ice.

American scientists also studied the issue in the 1960s, ie: this 1969 study from the RAND Corporation) (the quasi-Governmental "Research ANd Development" group, funded at the time by the U.S. Government). A 7MB Ebook of the 1969 study is available for free download from the link above.

The RAND Corporation study was reviewed in some depth here on the ASIB by Ethan O'Connor on September 24, 2012 at 08:52. Ethan provides a summary of the recommendations made in the 1969 study:

They conclude that the two most effective mechanisms for rapidly eliminating the central pack are albedo reduction and reduced net long wave radiation loss. Check, and Check, thanks to soot and net greenhouse forcing!

Indeed, it wasn't until the mid '70s that scientist seriously opposed these Arctic Geoengineering plans as too risky due to associated climate effects.

However, it's not obviously that major oil companies got the memo regarding the effect of "net greenhouse forcing" from increased burning of fossil fuels.

Or perhaps they did. Several U.S. Attorneys General are investigating what Oil Companies knew, and when they knew it.

Regards,
Lodger

Chris Reynolds

Tony,

I couldn't be bothered reading everything else, The Washington Post is a reasonably reliable source IMO. And from that Rignot doesn't seem to be saying Hansen's absolutely right, which means he may be wrong.

Isn't that what 'possibly in error' means?

Note I have learnt that when speaking to customers using terms like 'error' can be a mistake. A lot of people think error is something to the detriment, something to attract criticism. To an engineer (me) error may mean 'a difference from expected/nominal/actual', an error is often the crowbar needed to really break into new understanding. Just because something is 'possibly in error' doesn't mean it's worthless.

I still think Pfeffer's work on kinematic constraints regards Greenland's Outflow glaciers is right, but that doesn't mean I think: HE IS RIGHT!!!! AND ANYONE WHO DIVERGES FROM HIS OPINION IS AN INFIDEL!!!

Pfeffer's work on kinematic constraints is 'possibly in error', by the time we know for sure I'll be dead and buried - reflecting my firm expectation that multi-meter SLR within decades is impossible.

I stayed out of the argument purely because I did read that Hansen paper when it came out. It didn't strike me as world changing at all, to be frank I'd have to read it again to remind myself of what was said. It's certainly not in the same league as Roe's On the Defence of The Milankovitch Cycles or Wunsch's Abrupt climate change: An alternative view.

I really don't know why people are getting so worked up about what was a rather mediocre paper. Hansen has had some 'great hits' he probably will again, that one was a B-side.

bobcobb

Thanks Chris. Perhaps "questionable" would have been a better choice of words

D

Fish (George) here. I think that the weather and a slow down in the input of North Atlantic water into the Arctic led to the brief recovery and that first year ice does not have some property that makes it survive better than multi year ice. There is evidence discussed in peer reviewed journals that first year ice is much more easily melted out than multi-year ice.

I don't think there is a new regime related to more first year ice that delays melting. What's you're seeing is a coincidence where the weather was the primary factor.

Last spring the melting start quickly but then the weather cooled and the melting slowed.

This year ice extent is at a record low with record warm weather and a huge wind driven cracking event. The weather is in charge of how this summer's melting proceeds. Thin, relatively salty, first year ice will melt out quickly if it continues to be blasted by record heat.

FYI there is a pattern shift right now with the persistent Beaufort high breaking down a bit. However, because the jet stream is still strong over the Pacific, the wavy jet stream is sending heat into the Arctic ahead of the low pressure areas.

All the weather and climate models I look at show continued above normal temperatures in the Arctic but the winds will not be as persistent.

shwarzbarry

I remember the order of estimates from Maslowski and team.

2007:

"Our projection of 2013 for the removal of ice in summer is not accounting for the last two minima, in 2005 and 2007," the researcher from the Naval Postgraduate School, Monterey, California, explained to the BBC.
"So given that fact, you can argue that may be our projection of 2013 is already too conservative."

http://news.bbc.co.uk/2/hi/7139797.stm

2011:

"Scientists who predicted a few years ago that Arctic summers could be ice-free by 2013 now say summer sea ice will probably be gone in this decade.

The original prediction, made in 2007, gained Wieslaw Maslowski's team a deal of criticism from some of their peers.

Now they are working with a new computer model - compiled partly in response to those criticisms - that produces a "best guess" date of 2016....

"In the past... we were just extrapolating into the future assuming that trends might persist as we've seen in recent times," said Dr Maslowski, who works at Naval Postgraduate School in Monterey, California.
"Now we're trying to be more systematic, and we've developed a regional Arctic climate model that's very similar to the global climate models participating in Intergovernmental Panel on Climate Change (IPCC) assessments," he told BBC News.
"We can run a fully coupled model for the past and present and see what our model will predict for the future in terms of the sea ice and the Arctic climate."
And one of the projections it comes out with is that the summer melt could lead to ice-free Arctic seas by 2016 - "plus or minus three years".

http://www.bbc.com/news/science-environment-13002706

Maslowski made two predictions, one in 2007, and another in 2010/11 - ice-free by 2013 (possibly conservative), then ice-free by 2016 +/- 3 yr.

bobcobb

Good point, D. As Chris said, it will be a very interesting melt season.

Chris Reynolds

Bobcobb,

I'm not sure 'questionable' doesn't have overtones, perhaps it would be better. I'm extremely tired and recovering from a week with three 12 hour days (managing and doing the job). On that front though I have a new chap starting on Monday, I should have him doing useful work by the end of the week... So my work/life balance should massively improve just in time for the coming season's start. :)

Shwarbarry (Kevin & John),

Surely it's enough that Maslowski is (still?) talking about a rapid transition? However until I have gridded data from his model, like PIOMAS, I have no way to judge the strength of his argument. If his model indicates a rapid loss then why is it different from PIOMAS, which (IMO) does not indicate?

One problematic thing this season is that if we do see 2012 broken by a substantial margin that cannot be used to inform us as to the prospects of a rapid loss. I've been hit by that on the issue of Arctic Ocean volume, April volume seems to support my claims that April volume loss has stalled at around 19k km^3. But this winter has been so weird I can't really claim that, likewise a crash this year might be as a result of the extremely warm winter, not part of a continuing underlying process.

George,

Not sure who that was directed at, but: Yes. First year ice definitely melts more easily than multi year ice.

Rob Dekker

Regarding the volume-extent relation in this graph

http://2.bp.blogspot.com/-TA4qFR0WL1A/Uy3G1FUQS6I/AAAAAAAAAPU/VSrpuRhbE-Q/s1600/Extent+&+Vol.png

Chris Reynolds said :

That graph does not suggest an imminent collapse at all because it conveys no information about speed of progression along the power function trend.

If that is correct, Chris, then you are suggesting that we should see at least some slow-down in the rate of volume decline as we approach zero volume.

Wipneus' graph there is educational :

https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/piomas/grf/piomas-trnd1.png?attachauth=ANoY7cr1EgLYeorAIgv4_R91UXUrZQlkAR3Yq6e3yIGLb0aK2LOiOAFh2C8n1HzJMGCgLmr3FJ5Q-sqCqJKdZCr3M-SIPyOsRa6DodlWr_4xRCtG1Wv8225wyLnJfK6yAMf5z7LkNzg4jEZT0GPEcvHhJ8ZvZwWu4j_Db85g16G97JLrQgsTnYbbaT34roSLtkKPAVIV4RNegWzQA04JmJ4bd5I6lwugAwpnhQzE6wHixbyqazIqB9ttut8tCqQhVg2JPFUp_iF7&attredirects=1

You can sure argue that the recent (2013/2014) rebound is an indication that indeed volume decline will slow down.
However, with 2016's record minimum maximum volume, if we assume a melting regime of, say, 2010 or 2012 over the summer, 2016's September volume will end up at about 3,000 km^3.
Which is clearly in line with a continued (linear or even steeper) decline in volume, suggesting that after all, we are still heading for a collapse within a decade.

Rob Dekker

Not to mention that there does not seem to be any physical reason why the decline in volume should slow down.

Yes, the thickness growth feedback slows down the decline in WINTER/freezing volume, but it does not make it increase. And SUMMER/melting volume loss does increase with increased summer heat and reduced spring snow cover.

Kris

Third century this year (and the second this month) at ADS-Japan, minus 117.326 km2. And hitherto there have been this May three near centuries too. So the Arctic is exposed now already to a decay which usually only takes place end of Juin --> early July.

Bottom line, and as it already had been told in February, it is as bad as it looks like.


Chris Reynolds

Rob,

Overall volume being low this year is not instructive as it has been held down by low volume in Barents and Bering.

The melting action in summer that counts towards the September minimum is within the Arctic Ocean. Arctic Ocean volume was similar to recent years indicating a post 2010 transition to a predominant first year ice state with volume decline arrested due to the thickness growth feedback.
https://1.bp.blogspot.com/-hr4CUTflT7c/Vyo0BWhRz0I/AAAAAAAAC7c/4cFH6QRb-wo_kCiFiKJim-v_8hIeojpsACKgB/s1600/April%2BArctic%2BOcean.png

19k km^3 is roughly the April volume one would expect for 2m thick ice, i.e. first year ice growth.

The volume decline has mainly come from thick multi year ice. So the curve extrapolation you present is meaningless with regards information about the future.

So here is your decline in volume to which Wipneus has fitted an exponential/logistic function. But I have calculated contributions from three bands of gice thickness

https://farm8.staticflickr.com/7102/26934053601_d44a13b1d5_o.png

Now, as long as there is ice over winter in the Arctic there will be mechanical deformation topping up the amount of thicker multi year ice. Until we see regular ice free state in late summer the thicker band in summer will be there, but expectation of further decline then eating into thinner ice neglects winter growth processes.

If we look to April volume we see an even more stable picture.

https://farm8.staticflickr.com/7286/26908438862_02983110ae_o.png

Whilst the thicker ice has plummeted the thinner first year ice has remained stable and despite a drop in the last few years is still higher then in the 1980s.

So what this means is that the trend of decline of thick multi year ice is taken over by the trend of loss of first year ice volume. This is shown for Beaufort/Chukchi/East Siberian Sea thickness.
https://farm8.staticflickr.com/7270/26728691160_f60a55b9b1_o.png

Note how they have converged as winter growth processes stabilise the region.

Now all of these seas are very close to becoming regularly ice free at the end of the summer. But note, that is at the end of the summer. To allow massive inroads into the Central Arctic they must melt out much earlier. Say we need to get the April thickness down to 1.5m* for early melt out and a chance of losing enough of the Central Arctic for extent in September to be 1 million kmsq; the linear (not exponential!) decline of thickness in those regions suggests we're looking at something towards 2030 before that's to be expected.

*The 1.5m is arrived at by considering the PIOMAS -1m experiment run for Ed Blachard Wrigglesworth.

Summer losses are increasing, ignore a stabilisation of winter volume and the April volume vs summer loss curves meet in around 2020 (Central Arctic data to 2014). Factor in the stabilisation of April volume for the Central Arctic and the curves meet around 2030.
http://dosbat.blogspot.co.uk/2015/05/the-slow-transition-central-arctic.html

BTW - Summer warming in the land/ocean around the Arctic Ocean (60 to 70degN) follows a linear, not an exponential trend.

PS, I think you mentioned melt pond formation at present (or at least low ice albedo). I've been getting data together for a post on the atmosphere in May. Most of the pack has been colder than in 2010, temperatures are well below zero.

The only melt pond data I know of is here:
ftp://ftp.icdc.zmaw.de/arctic_meltponds/

Do you have a current source?

shwarzbarry

Bobcobb, no idea why M's predictions are generally sooner than the rest. They received a lot of attention in the press and skeptic blogs (for the most part), but I always considered them, for the little that's worth, too pessimistic.

The observed rate of decline is a serious concern in any case. Ice-free (<1 mil sq/km) is not a question of if. More interesting for those outside the zone is what that means for global change and weather patterns. People decades old inside the zone are witness to clear changes already.

Tony

Chris, I'm not really sure which Washington Post article you're referring to but you said "Rignot doesn't seem to be saying Hansen's absolutely right, which means he may be wrong." If it just "seems" that Rignot is saying Hansen may not be absolutely right, then that doesn't mean "he may be wrong". It simply means that, to you, the article gives the impression that Rignot thinks Hansen is not absolutely right. I think if Rignot actually said that the paper could "possibly be in error", then one might reasonably go away with the idea that Rignot thinks that Hansen is wrong. However, if he said "I'm not sure Hansen is completely right", then one might reasonably go away with the idea that Hansen is definitely on the right lines, according to Rignot, but may have a few things wrong. Those are two different impressions. However, from your comment, I get the impression that Rignot said neither of those things. Do you have a link to the article you were talking about.

idunno

Hi Chris,

WRT your para 1; I am not aware of that. Nor are the authors, nor you. Op cit: your last sentence.

Certainly, with the vast majority of extra thermal energy caused by FCAGW now stored within the oceans, we can expect that major oceans currents will begin to act in unusual, unexpected ways; almost certainly in ways beyond human comprehension, or computation.

Your data on airflow eliminates another possible variable from my "control experiment". So I think there is a very good possibility that extra thermal mega-giga-mega-giga-Joules have been flowing Northwards, at a shallower depth, this winter. I can't see why sunrise would affect this.

Weather in May is weather. Has the Arctic been experiencing inreasingly sunnier Mays since 1979?

Changes in ocean currents define new climates. In my view, the Arctic is, bathymetrically, a part of the Atlantic that looked a bit odd, when examined from above.

Weather in May: trivial interannual variation.
CO2: longterm downward trend.
Ocean currents: who knows? There may be some signs of mischief already afoot; and the extra OHC from FCAG can multiply its own effect by misdirecting existing forces, which have been accumulated, and stored as both kinetic and thermal energy, over the previous 4 billion

Rob Dekker

Chris said


Say we need to get the April thickness down to 1.5m* for early melt out and a chance of losing enough of the Central Arctic for extent in September to be 1 million kmsq; the linear (not exponential!) decline of thickness in those regions suggests we're looking at something towards 2030 before that's to be expected.

That's not what Wipneus' graph suggests. Depending on the exact curve you choose, and assuming a conservative 1 m ice left over in that last 1 million km^2, PIOMAS extrapolations suggests that we will hit "ice free" between 2019 and 2024.

Rob Dekker

Chris said :

So what this means is that the trend of decline of thick multi year ice is taken over by the trend of loss of first year ice volume.

But this is exactly why 2016 is worrisome.
Volume is low, because first year ice volume is very low this year. Which means that it will melt out faster than prior years, and, amplified by albedo feedback, summer heat will reach the inner Arctic ocean faster than prior years.

Which is exactly what we are seeing right now (JAXA reporting close to 11 M km^2 and on a rate of decline that is typically not seen until late June or July).
And with the fragile state of the Beaufort, I don't see how things are going to slow down any time soon...

Rob Dekker

Chris said :


The only melt pond data I know of is here:
ftp://ftp.icdc.zmaw.de/arctic_meltponds/
Do you have a current source?

No, I don't. Just like Dr. Slater, I rely on NSIDC's ice concentration data to estimate melting ponds. But with the F-17 trouble, that data is not available, and thus at this point we are 'blind' when it comes to estimating melting-ponds.
Your suggested atmospheric analysis (identify regions that are/have been above 0 C) it at this point our only hope.

Chris Reynolds

Idunno,

Are you answering my post on the PIOMAS thread - I can't figure out what you're referring to in your first sentence.

Tony,

It was referred to by Bobcobb on the previous page. I'm not going to continue this argument, the Hansen paper isn't worth it and I don't care about the Hansen/Rignot issue. I was asked to give my opinion by someone who trusts my opinion as I'm not wedded to the short term catastrophe camp.

idunno

Chris,

Yes, (sorry all for the incoherence - post was eaten by typepad, copied, and pasted, and reposted, in the wrong thread.)

Sam

Rob,

From the looks of the extensive shattered fracturing of the ice in the central Arctic and the fracturing bands now extending all along the shores of the islands from Banks to Ellesmere (especially in the last 12 hours), I rather suspect that melt ponds won't be much of an issue this year (if any issue at all). The ice simply appears unable to support them. The heatwave that is just beginning should have spectacular consequences to the ice.

On other notes...
I find it hard to imagine given the difficulties in setting up and supporting the runway for Barneo Ice camp this year that there will be many more years left for Barneo. Add to that the need to abandon staging through Svalbard and shifting to Franz Josef Land instead, and the conditions even for next years base look grim.

I doubt we will see the ice go below 1 million km2 this year. I wouldn't be at all surprised to see it reach between 2 and 2.5. And I would be very surprised if it fails to go below 3.

This is shaping up to be a spectacularly bad year for the arctic ice.

For the better part of ten years now, we have collectively struggled with understanding whether the ice decline would proceed uniformly in some manner (linear or exponential), whether it might at some point fall off of a cliff and do a state transition, or whether other factors might cause the end to go more slowly and taper off. We are very near the time of transition to an ice free Arctic in September. So far the uniform smooth transition (somewhat exponential) seems to be the winner, with the normal and expected annual random variations making it hard to cleanly tell any of these as being the answer.

At this point, we are so close, that I suspect that noise in the data wins out in the end. And I don't think it matters all that much anyway. The difference between 2010 and 2020 is a blink in the recorded history of man. It is very small compared to the last 400 years. And it is even moderately small in the period during which we have burned over 95% of the fossil fuels consumed so far.

The difference between these only looks big if we look in terms of the last decade or so since we began seeing the bulk of the ice melt. I would suggest that whether the 1 million km2 threshold is crossed this year, next year, or not until 2023 makes absolutely no difference at all in real terms.

By waiting until we have reached even our present state before dramatically ending fossil fuel use we have sealed our collective fates. There is no turning back now.

Chris Reynolds

Rob,

Wipneus has cautioned about relying on curve fits without reference to the underlying physics. I'll say it again, Wipneus's curve fit is meaningless with respect to the future, all it tells us about the future is what the fitted function 'wants' to do given the past data, one could select the function to suite your desires regards the future, meaningless. I am using physics and that trashes curve fitting.

First year ice volume is low purely because of volume outside the Arctic Ocean basin being low (Artic Ocean basin is Beaufort Chukchi ESS Laptev Central CAA). Gice profiles are here:
http://dosbat.blogspot.co.uk/2016/05/piomas-april-2016.html
The decline of extent at present is largely from outside of the Arctic Ocean basin. To quote from my most recent blog post (yesterday).

"The low overall extent is due primarily to Barents and Bering and the Greenland Sea, Beaufort continues to fall. Chukchi is starting to fall as normal, ESS remains flat at peak winter extent, likewise Laptev and the Central Arctic, the CAA is falling as normal. Within the Arctic Ocean Basin (Beaufort, Chukchi, ESS, Laptev, Central), only Beaufort is abnormally low and falling abnormally, compactness follows this pattern."

We do need an index of melt ponding. The best I can suggest is to watch SST in NCEP/NCAR, that's actually 'skin temperature'. The data could be downloaded in netcdf, but now they've chaged their netcdf format I can't use the data (I'm sick of NCEP/NCAR changing things for no reason). My thought however has been that you could watch it to see how areas level off at 0degC.

Here's daily composites:
http://www.esrl.noaa.gov/psd/data/composites/day/
Here's the most recent data:
https://farm8.staticflickr.com/7056/26927875022_f914822ba6_o.gif
It fits my expectations, which doesn't mean it's right. I could probably do with intercompairing with the limited period of data from Kaleschke (spelling?)

Here's how to set it up.
https://farm8.staticflickr.com/7171/27022032325_fcd0d0874b_o.png
Note the scale, the result is in Kelvin and 273.15K = 0degC, So I have centred on 273 and given a fine scale with a narrow window of +/-2degC (1K = 1degC)

2016 compared with 2013 for that day - worth checking out.

Idunno,

I'll get onto that other thread now. Thanks.

Chris Reynolds

Regards skin temperature.

Looking a bit more with those settings it would probably be best to grab daily images and look for persistence because patterns can come and go rapidly and may not indicate actual ponding unless they persist.

AbbottisGone

Chris, I note how espen on his forum thread waits a few days before commenting in general.... Looking for persistence I dare say !!

Smart move!

bobcobb

Sam, I would be very surprised if it went below 3 at all. I'm not sure where you're getting 2-2.5. That seems unlikely. And if you think we're doomed, which I highly doubt, there's a forum called Nature Bats Last you might be more at home on.There's no need for that apocalyptic crap. It's not helpful and a best uncertain.

Sam

Bobcobb,

What should be absolutely clear to everyone by now is that we are inexorably headed for a blue ocean event. Whether that starts this year or sometime between now and 2023 is of little to no significance. What matters is that we are going there.

With record high atmospheric CO2 (over 408 ppm at Mauna Loa this year, and rapidly approaching exceeding 400 ppm globally year round), and record stunningly high methane levels, and continuing increases in releases of both, there is at this point likely no chance that over the next decade or three that we won't succeed at having an essentially ice free Arctic winter.

As the Arctic continues to warm and as we lose power in the cold pole of the atmospheric heat engine, we quickly reach a point of destabilization of the atmospheric circulation systems. We are dangerously close to that now. We see tell tale signs of that now with the destabilization of the jet streams, the slowing of these, vastly greater oscillation of these and formation of things like the ridiculously resilient ridge that are already wreaking havoc globally.

Should we (when we) finally do cross that boundary, we cross a state transition. Everything changes after that. We lack even the most fundamental information to be able to adequately model what happens after that. We can paint the picture in broad strokes. But we certainly cannot adequately model the fine details or timing of the events to follow.

We can get a reasonable idea of the end state -> an equable climate world. But the transition likely will be neither smooth nor comfortable.

We should have avoided even the smallest possibility of such a thing with everything we have. Instead, our collective lack of ability to recognize and accept the consequences of our actions sends us on our way there at breakneck speed.

And we won't have to wait long for the answers.

bobcobb

The ridge isn't there anymore. The El Nino took out the blob that is connected with it.
What I mean is that saying it's too late in general is not necessarily true. Emissions have stalled over the last two years (which could mean global emissions may have peaked already), renewable energy is making great strides (still a long way to go), China's emissions trend is looking very promising, and India is focusing more on solar than previously though. Even so, there's a very long way to go and we're in for some tough times, but I don't think we're screwed. The Arctic Ocean will become ice-free in the summer at some point. Who knows when? But the extent of that can be limited. And let's not forget SRM as a potential wildcard. Now if a Repugnant gets elected here in the States, then that changes things for the worse. But I don't see that happening.

Sam

Bobcobb,

In the battle between El Niño and the Blob/RRR, El Niño prevailed. El Niño is now dead. La Niña appears to be forming quickly. The ridge though not solid as before is also reforming. In the past month it has risen, rotated, fallen, rerisen ... It will be back presently.

Do try to think in more than the present moment.

Chris Reynolds

Abbot,

It's exciting to be first with the word, but waiting means you can gain respect for more rarely being wrong.

I must pop into the forum.

Sam,

I think it far from apparent that we face a fast crash, as is clear from my discussion with Rob.

Equable Climate? What were CO2 levels in the Cretaceous And Paleogene?

Tony

OK, Chris. I was hoping you might point to the Washington post article you were referring to as bobcobb didn't link any Washington Post article on the previous page, or even in comments on the previous post. Maybe it was earlier, but I was hoping you might be able to point to it, since you spent the time to comment on it.

However, it's entirely up to you how you spend your time, but thanks for at least modifying/correcting bobcobb's position, as many others have done here.

bobcobb

Tony, my position still is more or less intact. Rignot has doubt about whether Hansen's projections will happen. Chris more or less supported my position

Chris Reynolds

Tony,

Sorry, it was the New York Times
http://neven1.typepad.com/blog/2016/05/beaufort-under-relentless-high-pressure.html?cid=6a0133f03a1e37970b01bb08fbbf1e970d#comment-6a0133f03a1e37970b01bb08fbbf1e970d

Wayne Kernochan

@Chris -- in hopes that you can get back to forecasting rather than wasting your time on Rignot trivia: Joe Romm has been pretty scathing about the NY Times' climate science coverage. I would take anything not written by Justin Gillis, who is imho superb but now mostly writes blog posts on climate change, with a large grain of salt.

My own view is that the piece is written by a relative newbie who is trying to find a "hook" to make it controversial. To take one small example of the inaccuracies, he states that "in the last year a small group of scientists have begun" considering what might happen in terms of greater-than-1-foot-by-2100 sea-level rise with melting glaciers and a few storm surges. (a) scientists have been considering these possibilities for a much longer time, as witness an MIT study that raised the possibility of as much as 10 feet of sea level rise by 2100 several years ago, iirc; (b) it's not storm surges but the increased height of storm surges due to greater energy in the winds of the atmosphere due to increased heat.

I speak as well from personal experience. In the early 1990s as a newly minted computer industry analyst, I happened to receive a call from a Times reporter about a new IBM version of a parallel computer. The reporter desperately wanted to come to one conclusion; I spent a good 15 minutes trying to persuade him that the facts didn't fit, but that there was another noteworthy innovation in parallelism to talk about. When the story came out, I found that he had butchered one of my explanations in order to make it sound like I supported his conclusion. To make it worse, I got loads of congratulations from people who didn't understand the subject matter but assumed that the NY Times must be right.

AbbottisGone

bobcobb,

It's my misfortune to inform you that America changes like clockwork and that a repugnant(lol) will, infact, become President.
I could be mistaken...

Rob Dekker

Chris, thank you for your perspective, your analysis and your insights.

Regarding curve fitting, yes, you sure have a point that they should be grounded in physics, but I am not convinced that you have the physics on your side. The remaining ice volume in September is simply the difference between the starting (maximum) volume (which is determined by winter) and the amount of volume that melts out (which is determined by summer).
There is no physics that somehow, magically, cause a "slow down" as that remaining September volume approaches zero.

Regarding your 2016 September extent projection (of a 2015-like 4.6 million km^2), I respect your opinion, but I think you grossly underestimate energy-input, and you grossly underestimate albedo-feedback during the summer months. So I think your are WAY too optimistic with that projection, and I put more trust in my "albedo" method, which has a lower SD, and suggests a September extent of 3.2-3.5 M km^2. But time will tell.

Incidentally, I'd like to run some numbers, to see how well my "albedo" method is in predicting September Volume minimum.
But that is something for a different thread than this one.

Rob Dekker

Sam,
With all due respect, but I have not seen any physics, or any study that project "an essentially ice free Arctic winter" over the next couple of decades.

Sam

Rob,

At every step along the way, science, physics, the accepted model has grossly under predicted the rates of change. This is not at all surprising. The origin of the failure is the omission of large critically important factors and feedbacks, as well as a general paucity of data to derive appropriate models.

What models we have are getting better with every passing year. Yet, with every passing month we learn more that we didn't know that bears directly on the problem and that highlights yet more positive self reinforcing feedbacks. If you insist on only using confirmed and validated models to tell you where we are going, your first indication of disaster will be the moment you fly off the cliff or smash headlong into a wall.

The IPCC consensus is woefully out of date, to the point of uselessness. More recent developments are better, yet the ice continues to surprise us collectively.

The steps from here to the future are plain and obvious. The questions are ones of timing and precedence. What comes first? What comes next? What do the timings of those arrivals tell us about the future.

As far as the science goes, it hasn't been good. We have had a truly immense application of type 1/2 errors (which depending on the framing of the question). We have collectively bolloxed it up by falsely and wrongly presuming we know all we need to know to accurately project future behavior. In point of fact we have almost uniformly gotten that absence of important and critical knowledge wrong in a systematic way that underrepresents the rate of change and collapse.

The coming reorganization of the atmosphere is yet another of these. That it has already begun is plain as day. Exactly how that works, we don't have even the basics to predict with any fidelity. What little we can project is already starting.

Hang on tight. The ride is going to be bumpy.

AbbottisGone

Well, I, for one, am more than interested to see how well Robs predictions come close to the truth.

Go Rob: you've done a lot of analysis!

Tony

Thanks for the correct link, Chris. So that seems to alter your commentary a little, as you mentioned Washington Post several times. The NYT piece doesn't quote Rignot at all in doubting Hansen's projections but does offer its impression that "Rignot does not think the oceans will rise quite so considerably", whilst also making clear that Rignot thinks the IPCC projections are probably far too cautious. He also thinks that the Greenland ice-sheet is gone at 2C, thus casting doubt, also, on the Paris agreement achieving anything that could be considered a "solution".

bobcobb, I realise that your own view hasn't changed, though I note that you're using much more vague characterisation of Rignot's position, which I guess, is progress of sorts.

Ghoti20

Instead of arguing about what various people have written about what Rignot says we can just listen to Eric Rignot himself.

He addressed the difference in his and Hansen's projections in a talk this past year.

Here's a link to the part where tells us.

https://youtu.be/3p9uRxX95f4?t=23m20s

By the way the entire presentation is great and worth watching.

Bill Fothergill

@ Ghoti

Thanks for that link to the AGU Fall meeting.


@ AiG "... America changes like clockwork ..."

Unless something seriously unexpected happens in the next 8 months, the 3 most recent incumbents at 1600 Pennsylvania Avenue will each have served the full 2-terms. As you have observed, their affiliations* have indeed been Dem (Bill C), GoP (George Dubya) and Dem (Barack O). (In the case of Bill C, I was only referring to Political Party Affiliations.)

However, I'm afraid your clockwork analogy rather breaks down if one looks any further back.

bobcobb

Abbott,
I'm gathering you haven't been paying attention to the polls that much or the demographic changes in the States. Clinton is beating Trump handily in the national polls and in the key swing states of Virginia, Pennysylvania, Florida, Minnesota, North Carolina, and Wisconsin. All she has to do is merely defend the swing states she currently has, while Trump has to basically sweep the Rust Belt. Not a likely scenario.
Also, Hispanics, women, and blacks have been growing in the population and turn out to vote in large numbers in the presidential elections, mainly for Democrats. Of course if they got off their asses to vote in midterms, we wouldn't have a repugnant Congress right now. Either way, I would be extremely surprised if Clinton doesn't win by a relatively large margin in the electoral college, especially considering she's competitive against Trump in states like Georgia.

Chris Reynolds

Tony, Wayne,

I still think it unlikely Rignot was misrepresented, did he complain?

We are talking about "Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming is highly dangerous" aren't we?

You see, it's not just amateurs like me that thought the paper unconvincing. William Connolley is a former modeller for the British Antarctic Survey.
https://en.wikipedia.org/wiki/William_Connolley

In October he reviewed the reviewers comments on the first version of the paper - which was rejected for publication due to the unfavourable reviews (by actual scientists in the field - not by the usual idiots). It's really not a pretty picture. I remember reading that and concluding my opinion of the paper was fair and I had understood it.

The NYP article was published in November.

But now I find that the paper has been substantially re-written. Via Rabbet Run in February.
http://rabett.blogspot.co.uk/2016/02/compare-and-contrast.html

I haven't read the re-write, but the whole argument was obviously based on the original version.

One thing I have always agreed on is that "2 degC global warming above the preindustrial level.. ..is highly dangerous." I just think that whilst at 2degC we will see very detrimental impacts, attaining 2degC opens up the great likelihood of catastrophic impacts in the following centuries. That expectation is biassed by my expectation that we'll burn all the fossil fuel we can get at - we won't stop at 2degC.

Chris Reynolds

Rob,

There's no magic in it, if April volume loss stalls then summer loss extent stalls. I agree that albedo is important, I just think you're expecting too much of it.

We'll have to agree to disagree and see what happens.

My prediction is based on 1979 to 2015 data, and merely reflects the impact of April volume loss on extent, it was never intended to be a totally accurate method, notably it fails in 2007 and 2012 - weather dominated years. I expect this year to be at the lower bound end (4.0M km^2) or lower.

But IMO my method totally rules out talk of an ice free state in September (or anything lower than 2M km^2 for that matter).

I would be interested to see hindcasts for your method (I think your method has merit). For what it's worth, here is my hindcast.

https://1.bp.blogspot.com/-ODDVBPRojrE/VypSGP0FVmI/AAAAAAAAC7s/Eg1TJH7WFUIt9JjMn4rPJCjY44IjieGGQCLcB/s1600/SIPN.png

Olivier_DelRio

I must say I agree with Sam. Paloegene and Cretaceous are too far in times. Miocene CO2 was around 400 - 500 ppm and this epoch saw equable climate. Faint Sun paradox, vastly different continent settlement, and so on, are against any direct comparaison with so remote times. Models would be far more usfull if we were seeing a cooling. Ice Ages have the same logic than our current climate. But for a warming with the certainty to flip to a new state, models are misleadings. Some good ideas from Kerry Emanuel about hurricane mixing and from Abbott about cliuds retroactions, but still we don't know how an equable climate really works... We will probably discover it in the second half of this century, if we are still there. For winter blue arctic, I must search about it. But at leat the US Navy, by the voice of admiral Titley, said one time that ice free conditions are a distinct possibility in the second half of this century (not sure of the exact wordings tough, but he was pretty clear about this).

Olivier_DelRio

P.S. Reading again I know doubt I was crystal clear, sorry my bad. I was perhaps a bit too emphatic about Cretaceous and Paleogene. It's true Cretaceous is really not directly comparable, but for Paleogene it's not so true yes. But still we have the max of the Miocene, its 400 or 500 ppm of CO2 and its winters frost free even in the far north and the probable lack of winter sea ice, its palm trees and crocodiles up to 40 or 50° N and so on. Miovene perhaps was not as equable as the Eocene but still the climate was probably way more closer to an equable one than to current setting of climate. And Pliocene probably never went above 400 ppm. And for the words of rear admiral Titley, I can serch youtube but he really speak about ice free arctic in winter in the 2nd half of this century. But we are now totaly outside of the main thred...

Artful Dodger

Rob Dekker wrote | May 16, 2016 at 06:36

"I have not seen any physics, or any study that project "an essentially ice free Arctic winter" over the next couple of decades."

Hi Rob,

This paper describes the physics:

Aagaard, K., & Coachman, L. K. (1975). Toward an ice‐free Arctic ocean. Eos, Transactions American Geophysical Union, 56(7), 484-486.

Abstract:

The strong salinity stratification of the Arctic Ocean prevents substantial ice-free conditions in winter by suppressing convection and reducing upward heat flux from the Atlantic Water. These conditions would be significantly altered in the sensitive southern Eurasian basin if suggested diversions of western Siberian rivers were accomplished.

Notice how scientists were still referring the goal of removing the Arctic sea ice pack in aspirational terms? [smh] Still, Google Scholar cites Aagaard & Coachman (1975) in 112 sources, making it a classic paper.

The physics behind the halocline and heat advection show that what affects the surface salinity affects the sea ice. Lose the salinity cap, lose the sea ice.

Yes, in Winter too. There's lots of heat held down below the Polar Mixed Layer: (click image for larger)

Vertical section through the Arctic Ocean - WikiCommons

The warm, salty Atlantic water is simply denser than the colder yet fresher Arctic mixed (surface) layer, and is forced to sink by gravity. Unless the two layers mix, the heat never comes to the surface.

So the risk to sea ice comes when increaing surface salinity eventually reaches a treshold, causing convective overturning in the water column and giving access to that huge store of Atlantic heat. This is what leads to year-round ice-free conditions.

It's just physics. But don't blame Isaac Newton. Blame those fossil fools. They've known for a long time.

Cheers,
Lodger

bobcobb

Oliver,
What do mean if we are still there? You're not a Mcphersonite, are you?

Artful Dodger

Hi folks,

Quick correction to my comment above regarding units for salinity (h/t to "John" over at Tamino's):

"Ocean salinity is defined as the salt concentration (e.g., Sodium and Chlorure) in sea water. It is measured in unit of PSU (Practical Salinity Unit). It is equivalent to per thousand or (or g/kg.

The 25 PSU value for sea surface salinity is important as the threshold where overturning cirulation starts to occur in a cooling water column, bringing up heat from below.

A "fresher" layer will freeze as it cools, a saltier layer will sink forcing warmer water to the surface.

If the warm layer is a thousand meter thick, it's not going to freeze in a single Winter."

More here, as usual. :^)

Cheers,
Lodger

Rob Dekker

Hi Lodger,
That article appears to be behind a paywall.
Can you summarize its findings and how it relates to the statement of "an essentially ice free Arctic winter" over the next couple of decades.".

But even without that : Yes, there is an astounding amount of heat built-up under the Halocline, and if that were to be released, we sure can sustain a couple of winters without ice.
But what happens after all that heat is lost ?
You stated earlier that an ice-free summer (after an ice-free winter) would accumulate enough heat to keep the subsequent winter ice-free as well, essentially suggesting that the Arctic appears in a "bi-furcation" state, where it either can appear with or without ice, and still be energy-neutral.
But is that really true ?

Rob Dekker

Chris said :

if April volume loss stalls then summer loss extent stalls.

This does not make any physical sense to me.
If summers keep on warming (due to global warming), then more and more ice (volume) will melt out during the summer.

So physics suggest that even if April's volume stalls (which is not clear at all at this point) then the final amount of ice left over in September will keep on going down. There appears to be no physical reason that decline would slow down, and thus it will go right down to zero (ice-free) and beyond.

Chris said :

I agree that albedo is important, I just think you're expecting too much of it.

Check out this graph of ice volume anomaly over the months :
https://14adebb0-a-62cb3a1a-s-sites.googlegroups.com/site/arctischepinguin/home/piomas/grf/piomas-trnd3.png?attachauth=ANoY7cpmN74ti-eQpKHAQ8q5v8g3_kUDhPTZcN54jJy2IJsDIVrGWYy1D4QzLNGOigVHgzFYG9V3XUW-sA5yvzgQe59uRll_VciM1H8godviXzoxAuo1V62qpnTuifmMDyjGBgZu0d4GRmk9WtU_nhpPWxLtAC_Nk-v1XlBoS9DYsBv-18fARBh539qM0kQsBgFR8qN9enu3nkUYF0DaQG7NeM9AYftFoDwRgjFKw-t5-Yd1FZ4cdrWFrhR3y6hso04mt-V771to&attredirects=0

That dip in June that has been developing over the past decade is exactly the effect of albedo-feedback.
And it is quite substantial.

Rob Dekker

Chris said

I would be interested to see hindcasts for your method (I think your method has merit).

I'm not sure about 'hindcasts', but here is the June forecast of my "albedo" method for 1992-2015 and how it panned out :
http://i1272.photobucket.com/albums/y396/RobDekker/June-14_zps7336859b.jpg
The June 2015 forecast for September was 4.6, right on target.

Artful Dodger

Rob Dekker | May 17, 2016 at 06:00 asked:

"That article appears to be behind a paywall. Can you summarize its findings and how it relates to the statement of "an essentially ice free Arctic winter" over the next couple of decades."

Hi Rob,

Yeah, the full article is paywalled. I can check at my University to see if we have the journal where it was published: "Eos, Transactions American Geophysical Union" Vol 56, from July 1975.

But an even more interesting paper to find might be this one, which examines the Soviet river diversion proposal with a numerical model:

Semtner Jr, A. J. (1984). The climatic response of the Arctic Ocean to Soviet river diversions. Climatic change, 6(2), 109-130.

Now this paper is also [bloody] paywalled, but the [free] 513 word Abstract is much more statisfying. Some highlights are:

  • A numerical model is constructed to evaluate the effect of river diversions on the circulation of the Arctic Ocean, including the climatically important response in the extent of sea ice.

  • Three equilibrium solutions are obtained by eighty-year integrations from simple initial conditions: the first with inflow from all rivers, the second with one-third of the inflow diverted from four major rivers (the Ob, Yenesei, Dvina, and Pechora), and the third with total diversion from those rivers.

  • When runoff into the marginal Kara and Barents Seas is diverted, either in part or in full, almost no effect on the halocline results in the Central Arctic.

  • In particular, deep convection does not develop in the Eurasian Basin, the possibility of which was suggested by Aagaard and Coachman (1975).

  • The vertical stability within the two marginal seas is considerably decreased by the total diversion of four rivers, but not to the point of convective overturning.

  • The ice extent remains nearly the same as before within the Kara and Barents Seas.

This result agreed with other research conducted by Soviet scientists, in that simply diverting Western Siberian rivers would not be sufficient to remove the pack ice.

So this proposal (and it was just that) failed because they didn't think it would acheive the goal, NOT because it was considered a bad idea to rid themselves to that bothersome sea ice!

[smdh]

Remember through all this the cause-and-effect we are examining: convective overturning in the Arctic basin and sea ice persistence.

processes in the sinking of NADW

And so, more about a scenario envisioned in Fletcher (1965) leading to an sea ice-free Arctic in my next comment. ;^)

Cheers,
Lodger

Artful Dodger

Hi folks,

So the study of a perennially sea-ice free Arctic is by no means a recent research topic. See this review of the "state of the science" from more than 50 years ago:

Fletcher, J.O. The Heat Budget of the Arctic Basin and its Relation to Climate, The RAND Corporation, Santa Monica, California, R-444-PR, October 1965.

Fletcher (1965), in an extensive evaluation (194 pages) of existing literature dealing with the heat budget of the Arctic, visualizes an ice-free Arctic in roughly the following manner:

  • In the Summer the ocean world absorb and store up to 90 percent of all incoming solar radiation.
  • This would imply a slightly cooler atmosphere and hence a small increase in the intensity of atmospheric circulation.
  • Greater amounts of evaporation would produce general cloudiness over the area.
  • During the Winter the ocean would slowly release heat stored from the summer.
  • Surface temperatures would be slightly above freezing in contrast to -35C under present conditions.
  • Advection of heat from lower latitudes would thus be characterized by a constant, vigorous, year-round zonal flow with cool moist Summers and warm moist Winters.

Again, paywall issues with the full 192 page report, but the above precis was included in the introduction to Norbert Untersteiner's 1969 report for the RAND Corporation. (Yes, the one and same eminent Professor of Atmospheric Sciences at the University of Washington whom Neven recently eulogized).

And yes, you can download the report in full for free from the link above. (RIP, Professor U.)

Cheers,
Lodger

navegante

Chris, based on current conditions and on the fact that June weather was (mostly) unfavorable for melting in 2015, I will use best judgement over your numbers and consider the lower boundary as an excellent prediction (well below 2015).
Thank you for sharing this work.

John Christensen

Reference from Lodger:


"A "fresher" layer will freeze as it cools, a saltier layer will sink forcing warmer water to the surface."

What is described here regarding the "saltier layer" seems to be the halocline of the Pacific and the Atlantic, where warmer waters enter the Arctic Ocean (AO).
The salty warmer water sinks as it moves northward and slides below the polar mixed layer due to both the higher salinity level as well as slightly higher density of water at 3-5C compared to polar surface waters of low salinity and temperature near 0C.

Of the two factors, the difference in salinity level (E.g. https://en.wikipedia.org/wiki/Arctic_Ocean)is typically believed to be more important than the temperature difference and
The low salinity level of the polar mixed layer is primarily kept in place by the river outflows into the AO from surrounding continents.

As the saltier water cools, it is placed between the colder surface waters and the Arctic deep water, which is also colder, so there is not overturning taking place, allowing for the cooling of the salty warm water to cause other salty warm water to reach the surface.

Therefore, while the next sentence would apply to a typical open ocean scenario, it does not seem to apply to the AO:

"If the warm layer is a thousand meter thick, it's not going to freeze in a single Winter."

So, I think the Russians are right; without significantly reducing the freshwater flow to the AO, it will be very difficult to break the salinity-based stratification of the AO water column, or at least that breaking this stratification would take considerably longer than for the Arctic to become ice-free for a part of the year.

Am I missing something here?

Artful Dodger

Hi John,

Well, in terms of "missing something", there are three things in play in the water column: the thermocline (the temperature gradient), the halocline (the salinity gradient), and the pycnocline (the density gradient).

When predicting whether a horizontal flow will sink or remain on the surface when it meets another, it's the pycnocline that matters. An example follows.

This graph shows the salinity-temperature curve for sea water of equal density:

http://i.stack.imgur.com/rIoFu.png

Imagine that points A and B represent two physically separate surface water masses, where Pt A is stationary inside the Arctic pack ice, and Pt B is in the Gulf Stream, headed North.

Both water masses begin with densities of 1.0275 g/cm^3 (see that they are on the same curve on the graph above). Pt A is at 0C and 34.25 PSU, while Pt B is at 10C and 35.62 PSU.

Now if the water represented by Pt B cools to 4C during it's trip North on the surface, it's density increases to about 1.283 g/cm^3.

So when B meets A, B sinks below A because it has greater density. That's how the pycnocline works. Think of it like a very long incline plane, where things (water masses) always roll down hill.

Hope that helps ;^)

It's obvious by reading the literature of the day that, even 50 yrs ago, scientists were concerned about the overturning circulation in the central Arctic. This ability to tap into a virtually inexhaustible reservoir of heat during the long polar night could ensure that once the fresher surface layer disappears, the pack ice isn't going to reform.

Sure, some fast ice will form around the cold continental shores of the Arctic and in shallow seas, but the central Arctic basin will be open all Winter long, heated from below by the overturning circulation, and insulated from space by clouds above.

And further, churned continuously by wind and waves caused by unceasing storms, driven by the temperature gradient between the central Arctic SST near 0 Celcius, and the land masses of central Siberia and Cda/AK near -30 C.

So we have to ask how could the polar mixed layer break down, if reduced river outflow is insufficient? We witnesses two of these factors in abundance during GAC2012:

  • Mechanical mixing due to wave action, and
  • Ekman pumping due to strong wind fields over a large area and a steep horizontal pressure gradient.

I don't really *care* that much about final September SIE. It could be ZERO, but if the fresh surface layer survives, the sea ice WILL reform. I have full confidence in that. There is an equilbrium state, and that includes pack ice when the Arctic has a fresh surface layer.

But September SIE could just as well be over a million, but if the surface layer breaks down due to powerful fall storms, the ice pack could be gone by New Year's day. And never come back. It's the tipping point, but we just don't know where SIE will be when that threshold is crossed.

I DO *care* about changes in the halocline profile of the water column. I think it's the independant variable in this planetary climatic experiment, and SIE is a dependant variable (with albedo feedbacks).

I say we need better monitoring of conditions in the central basin water column. But alas, this is not easy to measure with a satellite.

I'm all in favour of a fleet of new gliders to profile the water column.

Underwater Glider

Anybody got a spare winning Powerball ticket? The planet you save could be your own.

Cheers,
Lodger

crandles

Rob said:

"Chris said :
if April volume loss stalls then summer loss extent stalls.

This does not make any physical sense to me.
If summers keep on warming (due to global warming), then more and more ice (volume) will melt out during the summer."

Try the following for an explanation:

Summer extent declines for 2 reasons:

1. GHGs, warming of air and oceans. This reason continues to apply.
2. Less volume at maximum means thinner ice which disppears more quickly allowing albedo effect resulting in more heat absorbed and more melt.

If volume at maximum levels out a bit then reason 2 reduces in its effect.

Reason 1 continues but looks fairly linear and reason 2 declines in effect. Together this looks to give a reduced rate of decline.

David Madsen

While a debate about whether the arctic will become ice-free (in summer and year-round) this year, next year, in the next decade or in the next 25 years is certainly interesting on a micro level (and, of course, particularly interesting to readers/contributors to this blog), on a larger scale it is meaningless whether it a happens in 2016, 2023, or 2036. It is going to happen, and, on a geological scale, in essentially a nanosecond. What is critical is that global CO2 levels are going to exceed 450 ppm by 2030 (not may exceed, will exceed). Global average temperatures are already about 1.5 degrees C above the long-term average andt by 2040 or earlier they will exceed 2 degrees. Barring some unforetold technological solution for extracting CO2 from the atmosphere we will be crossing the 500 ppm and the +3 degrees thresholds a few decades thereafter. The arctic is about to change dramatically, as is the world, and those of us younger than about 60 or 70 will be unfortunate witnesses to that shift.

crandles

David Madsen said
"CO2 levels are going to exceed 450 ppm by 2030 (not may exceed, will exceed)"

I see a couple of problems with this rhetoric.

It seems to say there is nothing we can do about it therefore we may as well not bother.

A more hopeful message is that we are gearing up renewables as they are now becoming cheaper than fossil fuels. Even without carbon price or subsidies that creates incentive. There is a lot of deployment to do but starting to cut emissions to keep atmospheric level to less than 2.5ppm increase per year may be possible as long as sinks don't suddenly weaken. 407ppm+2.5*14=442ppm.
Last 10 years increase was 23ppm only 2.3 ppm per year.

Given possibility of such a challenge to what you are saying, if you are going to maintain a 'will' not 'may' stance, isn't it better to slightly reduce the claim to what is certain so you don't get challenged is this way?

idunno

Further to lodger's comments on salinity gradients...

The extra heat in the Arctic overwinter has been noted. This cannot, imho, be explained by the increase in CO2 from 400 to 404ppm. It cannot be explained by sunlight. There is no observed relentless season-long extra inflow of warmer air from lower latitudes.

There are some great oddities along the path of the Gulf Stream, at lower latitudes, with maasive positive anomalies off the US Eastern seaboard abruptly transitioning, round the Grand Banks, to negative anomalies all the way to Iceland, and beyond. See here...

https://robertscribbler.files.wordpress.com/2016/01/hot-water-hot-water-everywhere.gif?w=600&h=383

This looks to me like a very strong, heated Gulf Stream meeting, and flowing underneath, fresher water, flushed from the Arctic. The Gulf Stream heat then reappears in the Barents Sea. I should also suppose it is likely, having lost less heat to tha atmosphere than in a normal year, to enter the Arctic through the Fram Strait warmer, and thus more buoyant, than usual, thus displacing more of the "Polar Mixed Layer" per lodger's illustration above, and getting sufficiently close to the surface as to cause the observed +25C temperature anomalies. I can't see what else could possibly be the culprit for these massive SAT anomalies, the feeble volume growth overwinter, and now the extremely rapid start to the melt season.

David Madsen

Crandles:
For when we will break the 450 ppm mark for CO2 I refer you to the comments of Ralph Keeling the director of the Scripps Institute C02 group (https://scripps.ucsd.edu/programs/keelingcurve/2016/04/20/comment-on-recent-record-breaking-co2-concentrations/). You will note that he says 2035, not 2030, and I apologize for my mistake. I was doing it from memory (which I should learn not to do as it increasingly fails me). However, again in the greater scheme of things, 2030 or 2035 makes little difference.
I in no way am suggesting that we should not struggle to shift to renewables. We obviously must do that. However, I think that will be almost impossible to do it in the next 14 or 19 years. Remember that the Paris accords are geared to reaching only modest reduction goals by 2030. It is highly unlikely that you, or I, or the readers of this blog, or the billions of other people on this planet are likely to give up our cars, our microwaves, our computers, our furnaces and air conditioners, our high calorie diets and all the other things that go into creating the increasing C02 concentrations. While not everyone has such things, those that don’t are struggling mightily to get them. Even if we all switched to solar-powered electric cars tomorrow, we are pretty well locked into the current rate of increase that Keeling is talking about.
What I do think is that the campaign to switch totally to renewables is likely to be, at best, only partially successful. I wish, hope, and work towards that goal, but think it unlikely within my lifetime and probably yours that it will be achieved. If not, that means we need to start thinking about and working on technological solutions. I have no idea what those might be or even if such solutions are possible, but to rely only on a total shift to renewables and the elimination of our dependence on fossil fuels simply betrays a complete lack of understanding of human behavior.

John Christensen

idunno,

You should read this paper from 2011 (By: Kirstin Werner, Robert F. Spielhagen, Dorothea Bauch, H. Christian Hass,
Evgeniya Kandiano, and Katarzyna Zamelczyk) for findings on variability of Atlantic Water inflow via Fram:

Atlantic Water advection to the eastern Fram Strait — Multiproxy evidence for late Holocene variability

Sam

Crandles,

In my (and doubtless others) opinion, hope is only helpful when it can accomplish something meaningful. Otherwise it is a terrible wasted effort that assuages our fears while giving us a false belief and stalling us from actions that might be meaningful.

I believe David is correct in his original assertion. The year on year rises in CO2 levels are increasing. As CO2, methane and nitrous oxide (and other greenhouse gases) rise, they are triggering self reinforcing feedback loops that are and will for a time lead to even greater rises in level as natural reservoirs release their retained gases. This is particularly true of the seabed methane and the CO2 and methane in the tundra. Each of these are massive sources. And they are breaking down even as we while away our time chatting about it.

People need to know and understand just how dire the situation is.

There are things we can and should do. These actions 'may' slow the transition. And that might be critically important not just for man but for whole ecosystems and entire phyla of creatures.

We cannot now stop the transition that we have invoked by our actions and by our collective ignorance and arrogance. It is far too late for that.

From the data, it appears that the last time we could have stopped this transition was about the time Carter was the US President. Had we gone all in to stop carbon emissions and population growth then, we might have stopped it.

Now, well now all we can do is slow the rate of change and try to adapt as the whole of the world goes through one of the greatest extinction events in all of geologically recorded history. We can perhaps by our actions slow things and save some of that that would otherwise be lost.

But we can only do that if we act massively and immediately. And we simply won't do that. So hope is useless at this point. Fear on the other hand, fear may serve us.

Sam

Chris Reynolds

Crandles,

Stall was to strong a word, inflection is probably a better word. And in the summer it ushers in a new regime of greater variability in minimum extent. Do you know what Oct to March surface temperatures north of 70degN (NCEP/NCAR) have been doing over the last 10 years? They have levelled - apart from this year which is a clear outlier.

Rob, thanks for the hindcasts (for that is what that graph is), it's impressive.

I did say: "if April volume loss stalls then summer loss extent stalls." Obviously in the context of what I have been saying the word loss was misplaced, that should read "if April volume loss stalls then summer extent stalls."

It's late, I've done a 14 hour day after a 12 hour day, I face similar tomorrow, so I'm going to have to leave this until the weekend. I'm really sorry but little either you have been saying has changed my mind. But you have made me look again at the weather in 2010 to 2012 and that may have driven the spring volume loss, not ice thickness. You are wrong on winter volume, it has reached an inflection. I haven't read any serious challenges to all the work I've done on that issue. But you may have more of a point regards summer loss than I had thought before, thanks for that.

This might suggest we can use the current warmth over much of the pack to infer a large spring volume loss this year.

crandles

>"Do you know what Oct to March surface temperatures north of 70degN (NCEP/NCAR) have been doing over the last 10 years? They have levelled - apart from this year which is a clear outlier."

Jan to March
http://www.esrl.noaa.gov/psd/tmp/climindex.78.150.138.240.137.17.37.53.png
seems to be continuing upward possibly accelerating.

Oct to Dec
http://www.esrl.noaa.gov/psd/tmp/climindex.78.150.138.240.137.17.40.19.png
does seem to have levelled as you indicate.

Is there some explanation for this or is it just noise like ENSO that doesn't really affect what you would predict for trend going forward?

Oct and possibly later might be affected by heat absorbed by oceans over summer which is then given up before ocean freezes over. So I might give Oct a lower weighting when considering effect of temperatures on reducing winter volume. Last 3 years Oct might be low because ice extent at minimum was high, possibly partly explaining the levelling off?

Change to Nov to Mar and the levelling off is much less clear. Perhaps also changing to 75N to 90N.

Kris

Not that bright a news from the Obuoy front, only Obuoy 14 appears to be fully functional. All others are out, even Obuoy 13 which gave in at the 29th of April.

Anyway, Obuoy 14 mounts the border of the Beaufort Sea and the Central Arctic [very North of Barrow], so it's quite interesting to see what happens there.

And what we see for now is the ice has been rounded off, probably mainly caused by evaporation.

Looks like there won't be other webcams available in the Artic, due to financial restrictions. But as we never paid not even a penny for, we can't complain, can we?

Rob Dekker

Thanks for the compliments, Chris.
Volume is one of the (may be THE) most important indicators of the health of the Arctic, and thus warrants close analysis.
And you, in countless, detailed blob posts, have been an inspiration in that respect.

Thanks again for all your work, and your insights, and let hope that the 'slowdown' you expect will develop soon during this melting season. We could sure use it.

John Christensen

Thanks Lodger; and the density gradient really is a function of salinity and temperature.

The lines in the diagram seem a bit simplified, since water has its highest density at 4C, but again this difference is so small that the level of salinity largely determines the pycnocline or buoyancy of the body of water:

Temperature(oC), Density(kg/m3)
0 , 999.8
4 , 1000
10 , 999.7
20 , 998.2

John Christensen

Sorry, got that first line wrong, please disregard.. ;-)

John Christensen

Note to self: Seek and you shall find:

"However, the salt content of oceans lowers the freezing point by about 2 °C (see here for explanation) and lowers the temperature of the density maximum of water to the freezing point. This is why, in ocean water, the downward convection of colder water is not blocked by an expansion of water as it becomes colder near the freezing point. The oceans' cold water near the freezing point continues to sink."

https://en.wikipedia.org/wiki/Properties_of_water#Density_of_saltwater_and_ice

Let me go get another cup of coffee..

crandles

>Sam Wrote "So hope is useless at this point. Fear on the other hand, fear may serve us."

Perhaps it might depend on the audience and maybe a bit of both is needed. Maybe the fear is more important:

I would suggest possibly most important audience is people who make investment decisions. With renewable becoming cheaper it is a matter of deployment that takes investment. Do they put huge amounts into a safe but relatively small return over long period from renewables or something more exciting and riskier? If they are convinced that economy will collapse or at least there is significant risk of collapse unless the problem is dealt with then the exciting and riskier investments will look a lot less attractive. That doesn't work unless there is some hope that massive investments deploying renewables might work to avoid the problems.

Chris Reynolds

Crandles,

I chose October to March because it is the integral of temperature over that whole period that determines sea ice thickness over the winter. After March thickening continues within the Central Arctic, but thinning sets in within the periphery.

What I see in January to March is a massive increase in volatility that would likely confound any statistical confidence in a trend change. But the greatest rate of thickening is in the early part of the winter, not the later. This winter saw extremely anomalous warmth (that's an understatement!) over Jan to Mar, but that didn't reduce growth as much as might have been expected because that period is so cold. By December sea ice thickness (PIOMAS) in the peripheral seas of the Arctic Ocean basin was far from the lowest in the data.

I haven't got a clue why the massive variance increase in the later period of Jan to March should happen.

I think the overall levelling and the levelling in the autumn both result from the thinning of sea ice and decline in summer extent. For example, it is around 2000 that average thickness of Beaufort, Chukchi and the ESS all converge. About that time Gice shifts from a continuous presence of thicker ice categories over 3m thick to a more sporadic pattern. Also about that time (2002) ESS summer extent collapse, a similar pattern, though a few years earlier happens in Chukchi and Beaufort (although Beaufort still has exports that cause large summer extents).

My guess is that those seas largely transitioned to a first year ice state then. and it was this that dominated atmospheric warming (e.g. Screen et al vs Graverson).

Put simply I suspect that winter warming has hit a period of diminishing returns and the early gains from the transition to a first year pack (almost all gone in the summer) have been had - so the winter warming levels.

Sorry for no graphics, I'm eager to enjoy a night off having left work earlier than I meant to.

Bill Fothergill

@ John C

When I read your comment timed at 09:46, I was going to point you towards a certain Wiki entry on the properties of water (fresh & salt). However, you got there without any assistance.

I usually go for tea, rather than coffee, when the mental cylinders are clogged up.

;-)

Chris Reynolds

Rob,

I had worried that you might be offended by my statement that nothing you or Crandles said made me reconsider. That's largely but not totally true, predictions are a key test of any theory (and hindcasts made with the same consistent methods are as valuable as actual predictions forwards in time). Your prediction hindcast made me stop and think - OK back to basics.

What happened was that it was some years ago that I last seriously looked at the spring volume loss (Feb 14). When I looked again with the benefit of last year's temperatures it struck me: I could make a pretty convincing argument that the volume loss in 2010 was merely coincidental with the 2010 to 2012 enhanced spring volume loss, not causal. And that was it. With that a lot of my former reasoning came under question.

I'm going to drop the matter at the moment and return to it after this melt season. However this melt season won't have any impact on my reasoning. This winter has so clearly been an outlier and so likely has an effect into this summer (perhaps just due to the super EN we've seem - almost as big as 1998 I read today) that I don't think this year can be used to inform us as to the future...

Except that the warm winter may tell us what might come when winters are regularly as warm.

I've been rather distracted and excited today. I still seriously doubt that we'll see <1M km^2 this decade. If we had a continuation of the April volume losses, I'd be more open to that, but I really don't think that is happening within the Arctic Ocean, which is where it counts.

As I can reckon temperatures so far in May aren't as high as say 2010, but it's early days, we've got over a month to 21 June and it's quite possible we could see a really strong PIOMAS Spring melt right across the pack. To be able to use temperatures as a predictor would be great - get the picture before the PIOMAS June data in July!

Anyway I'm going to leave this issue and get some reading done, starting with the Solar Partitioning paper by Perovitch. I will have more to say in the Autumn, this summer I'm going to cover the summer events.

I just hope NSIDC get their data back on line, the loss of F17 is really problematic for my working. I can't baseline AMSR2 to 1981 to 2010 for comparison with NCEP/NCAR because the dataset is too short.

Rob Dekker

Hi Lodger,
I read the Maykut and Untersteiner paper from 1969.
And what a magnificent read it is !

I love the loose style of writing that was common in scientific literature these days, and the deliberations about how to remove Arctic sea ice (by means of coal dust or ice-lichens) is sort of offending, ironic and refreshing in a weird kind of way at the same time...

The core of the paper discusses their 1D ice growth model. And wow. The amount of detail in that model is astounding. Including influence of brine pockets, temperature profiles, snow cover, penetration of short-wave radiation, albedo changes over the melt season, and very detailed about ocean heat flux. Topped off with a brilliant implementation in a Fortran program that can simulate an entire annual freeze/melt cycle in 15 seconds on an IBM 7094.

One of these things :

with punchcards optional, since it has tape drives too.

Just amazing what these guys were doing while I was just learning how to ride a bicycle at that very same time.

Yet the paper has virtually nothing to do with Arctic bifurcation, or assessments of an Arctic free winter. For starters, the model stops if there is zero ice at any time during the year.

Later 1D models DID include ice-free conditions, and some of these models did indeed suggest that it may be possible to have the Arctic in two states : One ice-covered, as it is now, and one ice-free, where both could be in energy balance.

Wagner and Eisenman explained that such bifurcation in behavior in these simple 1D models is likely not realistic, since if you include lateral heat movement (such as in more complex 2D and 3D GCMs), the bifurcation state disappears.
https://scripps.ucsd.edu/news/research-highlight-arctic-sea-ice-loss-likely-be-reversible

And that kind of makes sense. After all, imagine an Arctic (in winter) that is warmer (0C) than the surrounding land masses (which are at -20C or so). That sure reverses the heat flow, cooling the Arctic ocean very quickly, and thus the planet as a whole would have to warm up quite a bit (dozens of degrees) before an ice-free Arctic winter would become a reality. And without a bifurcation state, that is not going to happen in the next few decades.

John Christensen

Hi Chris,

In your analysis, have you looked at the AO index and how this factor could provide additional explanatory information when combined with temperature?

It seems reasonable to assume that:

- Fall season(Oct-Dec): Clear skies leads to additional heat loss from NH continents and open water (AO-), therefore improving conditions for Arctic sea ice growth.

- Spring season (Apr-Jun): The reverse; clear skies (AO-) allow more sun radiation to reach the NH, melting snow faster, heating up open sea water, and creating melt ponds early.

Averaging the AO index for spring seasons since 2005 and sorted from negative to positive AO (For 2016, added '0' for May and June):

Year Av. Spring AO
2008 -0,58
2010 -0,40
2005 -0,40
2016 -0,37
2012 -0,18
2009 0,27
2007 0,29
2014 0,31
2006 0,46
2013 0,46
2011 0,46
2015 0,80

Strong melt seasons are clearly towards the top of the list and reduced melt seasons towards the bottom - with 2007 as a noted exception.

AO index for fall seasons (Oct-Dec) show a similar pattern:

Year Av. Fall AO
2011 1,49
2013 1,26
2015 1,05
2008 0,81
2006 0,59
2007 0,23
2014 -0,42
2005 -0,62
2012 -1,12
2010 -1,16
2009 -1,50

As can be seen above, fall seasons of 2011, 2013, and 2015 were cloudy, leading to overall reduced NH heat loss.

If you then combine the AO index of the preceding fall season and the spring season AO index, then you may be able to spot a record melt season coming up:

Year Total AO influence
2012 1,67
2016 1,42
2014 0,95
2008 0,81
2009 0,53
2007 0,30
2006 -1,07
2010 -1,10
2015 -1,22
2013 -1,58
2011 -1,62

What is interesting for the 2012 season with incredible volume loss compared to the prior year is that the AO numbers leading to this 1st ranking were from October 2011 to June 2012..
And even with neutral AO for May and June 2016, this season is already in a comfortable 2nd place by a large margin, indicating a very considerable volume loss from a year ago.

At the other end of the list it was also by the end of June 2013 possible to identify this year as having strong volume growth compared to 12 months prior.


crandles

Chris,

Thanks for the explanation. We seem agreed on Oct to Dec temps being caused by summer sea ice area. A step down in area then levelling of area results in a step up in Oct-Dec temperatures then a less steep rise or levelling of temps.

For Jan-Mar, I am more inclined to suggest different drivers for the temperature: GHGs and warmer air flowing in from lower latitudes. (0.9m thick ice or 1m ice makes little difference compared to 0m or 0.1m so summer sea ice area effect is greatly reduced.) Displacing polar vortex or not (maybe also wavier jet stream) can then cause increased volatility in temperatures.

I will accept that it is possible that there is a less steep rise hidden by noise and could take several years before this is revealed.

I see Screen et al say
"However, the presence of amplified warming
aloft hints that processes in addition to the increased transfer of heat from the ocean to the atmosphere resulting from sea ice loss have
had a contributing role in winter."

Maybe enough wriggle room to stick to my inclination for different drivers of Jan-Mar temps and to expect them to continue upwards without a slowing in the rate.

Neven

I'm back, everyone. I'll need a day or two to dig through all the comments and info (although I did manage to stay up-to-date in the Internet café) and then the regular programme will be resumed.

D

Nice work, John C. Likewise strong high pressure over the Arctic in January and February will thicken ice in the central Arctic and lead to high atmospheric heat loss as the ice and atmosphere radiates heat to the dark sky. That happened in 2013. Clearly, the strong Beaufort high in the bright months of spring is allowing sunlight to warm the ice and the dark leeds in the ocean.

The difference between 2013 and 2016 is stunning. (Fish Here)

John Christensen

Hi D,

Yes, I have looked at AO for other months also and while they will certainly have an impact (Especially clear skies in July or January), then the correlation with volume changes seems somewhat stronger for the months 'preconditioning' the melt or freeze period.

John Christensen

Example: January '16 had AO of -1,45, while January 2013 'only' had AO of -0,61, which in principle should have resulted in more volume growth in '16 than '13.

The negative AO index of 2013 seems to have had more impact than the AO of Jan. 2016, because preconditioning had taken place for the 2012/13 freeze, which clearly was not the case this past winter.

bobcobb

Sam,
I think you're overstating the importance of seabed methane. Indeed, all the evidence from the latest studies and from atmospheric methane readings suggest no substantial release from clathrates are occurring or will occur any time in the near future. More likely it will be a gradual release over centuries to milennia. For terrestrial permafrost, the work of Natali et al suggests gradual release on a centennial scale, largely dependent on RCP scenarios. As far as progress going forward on emissions, that really hinges on the elections in Australia on July 2 and here in the US in November.
David, the temperatures for 2016 so far add up 1.45C, but a La Nina is most likely to happen. When the effects of the El Nino die down and La Nina start to take effect, it's likely the average will drop 1.2 at max and probably around 1 at the minimum, maybe less.

Fufufunknknk

BobCobb,
You are full of bunk. After years spent on various weather sites, as well as lurking here, I can smell shills a mile off.

bobcobb

Fufu,
What an insightful statement! Did you spend hours coming up with that pathetic statement?
Btw, I can footnote everything I said. I can also spot shills, and you have the look of one

Neven

Gentlemen, let's not go there. We're all concerned about AGW and Arctic sea ice loss, one way or another.

D

Neven, bobcobb has persistently made his numerous criticisms personal. It smacks of trolling.

With regards to methane, the Siberian shelf is very shallow and has high levels of organic carbon in runoff and depleted oxygen levels. There's a recent paper that shows that carbon levels of river water flowing into the Arctic are increasing with the warming of the Arctic.

Thus, there's reason for concern that methane released from the seabed of the Siberian shelf will not be oxidized to CO2 before it reaches the atmosphere. Likewise, there's reason for concern that faulted and fractured sediments will not behave like stable layer cakes and that slow diffusion will not control methane release rates.

I take observations by shipboard research teams of active methane release in the Arctic seriously. Yes, I know that Asian agricultural methane increases are dominant now, but that doesn't make me feel better about the Arctic. The science of Arctic methane releases is very uncertain, in my opinion. -Fish

bobcobb

D,
I take it personally when I see doomers spread false alarm and make it seem like the world is ending, and I often find their arguments fall apart.
And shipboard observations support my argument about seabed methane: https://www.sciencedaily.com/releases/2016/05/160513111837.htm
https://agu.confex.com/agu/fm15/webprogram/Paper78877.html
Paul Overduin has done work in the Siberian Shelf area for as long as Shakhova has, and his conclusions are different: http://epic.awi.de/38284/
https://www.researchgate.net/publication/281892395_Coastal_dynamics_and_submarine_permafrost_in_shallow_water_of_the_central_Laptev_Sea_East_Siberia
To say nothing of one of the chief GHG monitoring scientists at NOAA: http://www.atmos-chem-phys.net/16/4147/2016/acp-16-4147-2016.pdf

fryingpan136

When I see business as usual philosophy and phrases like "doomers spread false alarm" I take it personally. If there is even a 1% chance of a large methane burp, then nobody is spreading false alarm. If you are not already alarmed, you are not paying attention.

Given the complexities of nonlinear systems and the "quicker than ever before" changes we have already made to these systems, concern is more than justified.

Neven, I agree with D, aka fish, I smell a troll.

Neven

Don't feed it then. ;-)

My opinion is that it isn't doomerism to say that Arctic sea ice loss - even if it doesn't continue at this unprecedented and unforeseen pace - may have very serious consequences, that in some ways could be interpreted as world-ending. I think that's realistic risk assessment.

I also think that people are justified to be worried about this. It's not fair to belittle this as 'doomerism'.

I will re-read the discussion to see if bobcobb is setting up strawmen, as I read very quickly these past two days to catch up, here and on the ASIF.

fryingpan136

Okay, thanks. And yes, I am guilty of "feeding".

bobcobb

Neven, I find it funny you take offense against me instead of someone like fufu. If you're going to judge people, at least be fair about it.
Fryingpan,
There's a difference between being concerned and overdoing it. AMEG is a textbook example of that. Of course I think abrupt methane release is something to consider and plan for, but it's a far cry to say the sky is falling. And if you're so concerned about trolls, then why are you jumping in right now instead of earlier.

Neven

Bob, I haven't taken offense, I haven't judged, and I agree with you about AMEG (although I'm not reassured that methane from permafrost and clathrates poses no risk whatsoever).

But you have to understand there is also a difference between criticizing the overdoing and criticizing the being concerned.

Again, I will re-read and judge (for myself), which will help shape future decisions, if necessary.

As for now, I'm preparing a last post on Beaufort events and will then start writing the first ASI update for this melting season.

bobcobb

Alright, I'll refrain myself

The comments to this entry are closed.