A new Arctic feedback (?)

Quote from the latest PIOMAS update (10 days ago):

There's just no end to this run we have had with anomalously warm temperatures, and storms blowing in from the Atlantic.

As we speak, a very powerful winter storm is battering the ice pack on the Atlantic side of the Arctic, as shown on this SLP map (source):

Lowest pressure was probably reached yesterday at 957 hPa, but it's still raging at 958 hPa right now. Remember, the GAC-2012 clocked in at 962 hPa, and the series of powerful storms we saw last August bottomed out at 968 hPa. Storms tend to be stronger during winter.

In the short term this might actually increase sea ice extent, as strong winds will be pushing out the ice towards the Atlantic, but in the longer term it will probably be detrimental to the ice pack, as a lot of the ice being pushed out is older and thicker. The storm and the moisture it brings with it, will also cause more snowfall, insulating parts of the ice pack so that the ice grows thicker at a slower pace, and thus be thinner than it could have been when the melting season starts.

The ECMWF forecast is showing another strong storm forming 9-10 days from now, but that's very far out, and so the forecast can change. But the storm we're seeing right now (I briefly mentioned it in this previous blog post), was also forecast 10 days ago and then came about. We'll have to wait and see what happens.

Now, what is causing all these storms and all that moisture to be transported all the way to the Arctic? We saw the same thing during last year's winter, but this time it's even worse. It might have to do with all the heat that the recent El Niño brought with it, but previous El Niños didn't seem to have such a marked effect. Perhaps it's something else, another reaction to Arctic sea ice loss, some sort of vicious cycle.

Yesterday this video was posted on Peter Sinclair's ClimateCrocks blog, showing an interview with Dr Jennifer Francis (Rutgers University)
at the AGU 2016 Fall Meeting this past December:

Another effect of this possible feedback is more clouds during summer, shielding the ice from the Sun's rays. But as we saw during last year's melting season, this didn't help much (except for preventing new sea ice extent/area records). That's probably because heat doesn't just enter the Arctic via the atmosphere, but via ocean currents as well.

Comments

[Paddy]

Speculation: If the storms calm down for most of February/March, peak Arctic extent may not be especially low, as a thin layer of ice might still have time to form in the usual places, and the exported ice may work as something of a seed if it hasn't been blown too far.

Even in this optimistic scenario, however, volume would remain pretty low, and the ice that does form would likely melt fast

[Rob Dekker]

Thank you Neven.
I am not a meteorologist, but it seems to me that these storms reach the Arctic since the jet-stream appears to meander high up north over the Northern Atlantic this winter :
http://www.atmos.washington.edu/~ovens/wxloop.cgi?npole_h250_wind+/-168//
Could that have to do with Northern Atlantic sea surface temperatures which have been getting warmer and warmer over the years ?

[Ac A]

And Arctic temperature is spiking again. Not good.

http://ocean.dmi.dk/arctic/meant80n.uk.php

Alex

[Neven]

One can clearly see the storm bringing in the heat, almost above freezing temperatures at the North Pole:

[wayne]

Well Neven,

More than 22 Km/day drift for the entire Pack North of Ellesmere Island all the way to Russia, is no longer the pack I knew for decades. This means the greatest amount of open water in the densest zone ever. What is left of clear air in darkness is equally warm, clouds have dominated for so long the land, the ice itself all is warmer. Over all circulation is "l" shape like 2013, favorable for clouds to reign beyond the soon to be maxima.

Waiting for dark horizon data to confirm all this, but clouds, relentless fog horizons causing hoar frost hinder observations:

http://eh2r.blogspot.ca/2017/01/arctic-atmosphere-is-not-only-thing.html

to be completed tonight....

[PatrickLogicman]

An increase in average wind speed tends to be accompanied by an increase in gustiness.

The speed of wind gusts can be many times greater than the average speed.

A new patent law ruling in the Court of Appeal contains this gem at paragraph 100:

"the evidence given by Professor Leith in his first and second reports to the effect that wind speed and gusts are not independent of each other and that an increase in average wind speed tends to be accompanied by an increase in gustiness."

Read more here:
http://www.bailii.org/ew/cases/EWCA/Civ/2017/5.html

or here
http://www.science20.com/node/224835

[Remko Kampen]

This is no time for sabbatical... So sorry Neven.

[Rob Dekker]

A bit off topic, but the SIPN post-melting-season analysis report is out :
https://www.arcus.org/sipn/sea-ice-outlook/2016/post-season
And special congrats to Nico Sun (Tealight on the Forum),
http://forum.arctic-sea-ice.net/index.php/topic,1749.50.html
whose work on Albedo Warming Potential (AWP) receives special attention in this report. Great work, Nico !

[Bill Fothergill]

Rob,

Your comment and Nico's work on albedo effect triggered a long-forgotten memory. I knew that I had seen a denialist take on this from way back.

A couple of minutes on Google found the article in question...

http://www.warwickhughes.com/cool/cool13.htm

An alternative perspective can be found here...

http://www.pnas.org/content/111/9/3322.full

How do you think they stack up against each other?
(Don't try to reply until you have stopped laughing.) ;-)

[Rob Dekker]

Bill, thanks ! No comparison.

Such a silly post by Eschenbach. I always enjoy posts by climate science deniers, and Eschenbach is definitively one of the least professional ones.

I especially like the part where he presents Ireland records in a post that deals with the Arctic. Classic !

[Yvan Dutil]

Speaking of feed back. This is an interesting paper on the formation of melt pool on sea ice:

https://www.sciencedaily.com/releases/2017/01/170123145213.htm

[Neven]

Yes, I saw that too. And other interesting stuff that has been in the pipeline for a while now:

A Weekly Arctic Sea-Ice Thickness Data Record from merged CryoSat-2 and SMOS Satellite Data

[Robert S]

Hmm... interesting work in that sea ice thickness paper, Neven, but when, as shown in table 2, the standard deviation goes up for the combined/interpolated product as versus the source data, I'm not sure it represents progress. What it appears to be telling us, really, is that the two sensors and their interpretations are giving answers consistently so different that we need to find the sources of systematic error before we even consider combining them. A thickness estimation of 1.3 m +/- 1 m is, well, not terribly useful.

[Robert S]

I must say, that melt pond paper is one of those sort of hilarious "we've proven that the sky is blue" efforts, demonstrating the blindingly obvious. This process occurs on my street all the time, converting porous snow to a skating rink, although in my case the water is wicked from below...

[D]

George aka FishOutofWater here.

The oscillation of warm pulses from the Atlantic and Pacific sides into the Arctic may leave this winter's minimum extent close to last year's but all the water vapor clouds and heat will keep the ice from thickening much. Both the ECMWF and GFS models continue to predict the stratospheric polar vortex will be displaced towards western Siberia.

This means that heat will continue to enter the Arctic as Atlantic air will warm western Siberia and Pacific air will warm eastern Siberia and the Arctic ocean. That's what both models show. The 240 to 384 hours GFS 10 mb progs show the polar vortex in terminal spring decline. This situation seems to indicate that snow melt will come early to Eurasia this spring.

All in all the models are not forecasting good conditions for increasing ice thickness very much. Some of what we think is ice may contain submerged snow that is weak, low density material full of air bubbles.

The Jennifer Francis interview is excellent. We have been observing the same patterns here and interpreting them in a similar way. She does a great job explaining it in under 2 minutes.

[Rob Dekker]

Robert S, I think that table 2 in that paper refers to the standard deviation of the ice thickness found. So that number should be OK to be large. It's just what kind of ice thickness was found across the Arctic with each method.

What is more worrysome is the poor correlation they find in the validation runs against EM thickness measurements (AEM).
These AEM measurement are pretty accurate, and the poor correlation between AEM and Cryosat 2 as well as SMOS and their own method (CS2SMOS) as presented in the scatter plots from figure 13 and table 3
http://www.the-cryosphere-discuss.net/tc-2017-4/tc-2017-4.pdf
are quite poor.
That is not very encouraging for either Cryosat II or SMOS measurements, in my opinion.

[D]

"in the longer term it will probably be detrimental to the ice pack"

I thought that ridging of the sea ice was a pretty important method by which thicker sea-ice was created. I would have thought that the winds from the storm would cause quite a lot of extra ridging, with the open areas in the ice pack created as a result freezing over pretty rapidly.

So a succession of winter storms could help to create a thicker ice pack. Maybe?

It's sort of the flip-side to the argument that snowfall would insulate the ice pack, and slow down the thickening of the sea-ice. The open areas created by the storm will create ice more quickly (by losing heat more quickly) than a normal patch of sea-ice would, so the Arctic-wide volume of sea-ice would increase more quickly.

[Jim Hunt]

As we speak another very powerful winter storm is down to 953 hPa:

[wayne]

Very convincing evidence Jim,

The Lows gravitate and persist where there is more open water or thinner sea ice, they last long enough to merge with the next Atlantic one from the South, and so on. If there was an Anticyclone there, sea ice would accrete more, Highs "reject" or "repulse" Cyclones. During normal long nights not so far back in our past, the sea ice was so thick it generated Highs. I haven't seen one yet from the Frozen Ocean, they came from the South where the cold thrives over land in darkness.

There is a couple of things going about, the clearer recent weather is normal, is from the drying from the great long dark skies, but nowhere as cloudless as in recent past, the biggest area made apparent by this was North of Greenland and Ellesmere, when temperatures commonly dropped to -45 C. -30 to -34 on your map is par to present course of 10 to 15 C above normal weather, Note the
High, represented correctly as there is clear air there. No question about thinner sea ice with more leads contribution, this is the place when -50 thrived. The over all Arctic temperatures are also warmer than last year at present.

Venus helped confirm this warming:

http://eh2r.blogspot.ca/2017/01/blue-venus-oracles.html

our sister planet is always sexy.

[Hans Gunnstaddar]

https://www.washingtonpost.com/news/energy-environment/wp/2017/01/26/reports-on-climate-change-have-disappeared-from-the-state-department-website/?utm_term=.523267806551

The link has all the info. needed.

[Rob Dekker]

Hans, we are entering the dark ages here in the US.
I'm sure that this (and the gag order on the EPA scientists) is just the beginning. It's going to be really bad.

[Robert S]

Rob: You're quite right about what the standard deviation in Table 2 in the paper meant - silly me! Although it's an odd sort of measure... And you're quire right about the problems vis-a-vis the AEM data.

Unfortunately, at the rate we're going, all of these issues will be more or less moot in the summer pretty soon...

[StuartP]

A bit off topic here, but a question for you good folk who know a lot more about this stuff than me.

There is a huge area to the south of the West Antarctic that normally would be expected to have sea ice up to the edge of the land. This year that sea ice has completely melted out.

Any idea on what (if any) effect that is having on the melt rate of the ice sheet in west Antarctica?

[Jim Hunt]

Since you mention the ice sheet in west Antarctica, the Pine Island Glacier is calving once again:

http://forum.arctic-sea-ice.net/index.php/topic,429.msg100742.html#msg100742

[Bill Fothergill]

Larsen C is not looking too good either - although that's really part of the Peninsula, rather than the WAIS.

http://earthobservatory.nasa.gov/IOTD/view.php?id=89257

[Paddy]

@StuartP,

I'm no expert, but between loss of albedo, loss of protection from wave action, and possibly loss of a little direct mechanical restraint, I can't imagine sea ice loss helps the stability of sheet ice or coastal glaciers.

[wayne]

Paddy,

The Arctic Ice Shelves , not unlike Antarctica, are on their way to extinction despite a much more stable pack ice, virtually every day of the year presence.

Last 3 days were warmer than same days last year. It doesn't look promising.

[Susan Anderson]

Thanks for the forum reference on Antarctica. Chris Mooney at WaPo and Andrew Freedman at Mashable have an update on the long Larsen C crack (another 10 km from January 1-19). Earth Observatory is full of wonderful material, including this: First Light from GOES-16
January 26, 2017
http://earthobservatory.nasa.gov/IOTD/view.php?id=89506&eocn=home&eoci=iotd_grid

http://mashable.com/2017/01/20/giant-iceberg-about-to-break-off-antarctica/
Don't know if it's relevant, but temperatures in Chile are in the 40s (110Fish) with wildfires, which can't be good. They should be heading into darker cooler down there in a few short weeks.

[wayne]

A look back of the last Month using Infrared imagery brings out a severely displaced habitual cooling place. Once upon a not long time ago, Northern Ellesmere had immersed glaciers, such as Ward Hunt ice shelf, thick and wide for a reason. Surface temperatures in darkness were extreme there, the recent record as seen by satellite pictures reveal a near non existent deep cooling:

http://eh2r.blogspot.ca/2017/01/barely-familiar-arctic-sea-ice.html

[Jim Hunt]

Susan - At the risk of drifting further off topic, and despite its name, the Arctic Sea Ice Forum has numerous updates on Larsen C:

http://forum.arctic-sea-ice.net/index.php/topic,1175.0.html

[Susan Anderson]

Thanks Jim, hope others will note this is off the reservation. The link is helpful, and I found a proper map in my bookshelves as well. Time to go back to school for me! ;)

Do have a look at the new GOES picture I linked, just for the beauty. Still off topic though (slaps self on wrist).

[Angela Marchbank]

Hello all, a long time lurker here, I have read, learned and enjoyed this site now for many years and particularly over the recent months with all of the worrying developments and animated discussions. However I am a little concerned. Where is everyone over the past three days, no posts. Is there a problem with the site?

[Elisee Reclus]

Angela--

Maybe we have exhausted our speculations. We need more data.

NSIDC will publish its January SIE summary within the next few days and we'll have something to talk about. I'm looking forward to it. It should be a doozy.

[SimonF]

I am also a daily lurker and I noticed the lack of comments as well. One question I have left no wanted to ask. What does the April sea ice volume need to drop to in order to make a virtually ice free September likely? I would guess at anything less than 20 000 km3.

[navegante]

Just in case anybody is missing it, there is a lot going on over the forum
http://forum.arctic-sea-ice.net/index.php/board,3.0.html
And with a lot more pics!!! :-)

[Paddy]

SimonF,

I'm no expert, but based on this graph (https://d3800158-a-62cb3a1a-s-sites.googlegroups.com/site/arcticseaicegraphs/longterm/PIOMAS%20min-max.png?attachauth=ANoY7crVHP6iyp6k4piKYFJ8Tyv2SeJcNlyCPqhWj9LfECHqFZWpupdjr6wALn3OJgkYJiiD1WFfGgtGza9Q4sPwvprBxA5LHuBcxKfBzIb46VgrXTHKxdoPZqCW6An6qyAOOj-omAuDwUalWvRNcmHZe8OWyY6UZhZf4gVZIMdyOrHvAZwmE4FhMwoIfpR2ynOX1d4UMUepSxdSFXrsy8vopVh4WTxWPuOjFkGQuka6hqfbEodBTiI%3D&attredirects=0) the typical annual drop from maximum to minimum is about 17000 km3 or so. Of course, this may increase with albedo and ice fragility feedback the less is left at summer maximum, and "I've free" is generally taken to mean an extent of <1 million, so your figures of 20,000 km3 doean't sound far off.

[Paddy]

*Ice free

[jdallen_wa]

SimonF, this year, we may be making a serious run at "Ice Free"; certainly to get well under 4000KM3 of volume.

As indicated above, come over to the forums to see and follow the mixture of fascination and terror in our discussions.

[Neven]

Where is everyone over the past three days, no posts. Is there a problem with the site?

It is indeed mostly because of the Arctic Sea Ice Forum where it's easier to post images, and there are more thrads specific to different subjects.

But things have always been quiet around here during the freezing season, although I think they would be a lot less quiet if it weren't for the ASIF, given that this freezing season is even more abnormal than last year's.

Total annual volume loss in recent years according to PIOMAS (max-min between brackets):

2006: 16198 (25191-8993)
2007: 17345 (23803-6458)
2008: 18087 (25159-7072)
2009: 18235 (25074-6839)
2010: 19693 (24275-4582)
2011: 18375 (22677-4302)
2012: 19692 (23365-3673)
2013: 17940 (23332-5392)
2014: 16306 (23118-6812)
2015: 18698 (24394-5696)
2016: 18316 (22717-4401)

PIOMAS is going to update in a few days. It will very likely still be lowest on record.

[Jim Hunt]

Angela - As Navegante perhaps implies, it's much easier to display images over on the ASIF than here on Typepad, so check the "2016/2017 freezing season" thread regularly too.

By way of a quick overview, following a spurt due to a cold snap on the Pacific periphery Arctic sea ice area is currently flatlining:

Somewhat more unusually there's currently a Sudden Stratospheric Warming event over the high North:

[navegante]

Thx Jim, yes I have heard, see link below, the ongoing SSW which will be affecting the Arctic in February and March. The problem with the SSWs, apparently, is that their actual impact is very difficult to assess (not only the current PV diversion, but afterwards). But some effects it will produce:

https://www.aer.com/science-research/climate-weather/arctic-oscillation

[Jim Hunt]

Judah Cohen is currently busy at the "Arctic Change and Its Influence on Mid-Latitude Climate and Weather" workshop. There doesn't seem to be a live video feed unfortunately, but James Screen seems to be busy live tweeting:

#Arctic17

Lots of posters from the workshop can be seen at:

https://usclivar.org/meetings/2017-arctic-midlatitude-workshop-poster-gallery

[Angela Marchbank]

Neven, Jim, Elisee and others. Thank you for your answers. I will indeed look at the forum to keep abreast of ongoing events. I very much look forward to the next post. Always informative, thank you Neven for helping make the complex but important events related to our climate ( and our impact on it) accessible to us non meteorologists and climatologists

[Rob Dekker]

Regarding that feedback, of increased moisture penetration into the Arctic, and its influence on Arctic climate, this paper Vihma et al 2016 provides some meat to that. For example :

feedbacks associated with the increase in atmospheric moisture and decrease in sea ice and snow cover have contributed to the Arctic amplification of global warming.

Full paper here :
http://onlinelibrary.wiley.com/doi/10.1002/2015JG003132/full

[Geert Diederen]

Hello there, I am wondering what will happen if in a few years no ice will be left over in the arctic to melt... the heat that now goes into the ice to melt it, must go somewhere else like the sea itself and I am wondering if models have taken into account the extra accelleration (feedback) this will bring about in the rising of arctic and global temperature rise... this must be, I guess, a big contributor to extra heat absorption in the oceans...

Is there someone who can tell a bit more about this soon to happen phenomena? I would be pleased...

Furthermore with the extra heating of the ocean in the Northern Hemisphere, how long will it take that this extra heat have its effect on Antarctica? And in what manner and accelleration and timeleap...

Thanks,
Best regards,
Geert Diederen
The Netherlands-Europe

[Elisee Reclus]

Geert--

I expect the solar energy that would normally go into melting the Arctic Ice, as well as the sunlight that is now reflected back into space by the icecap, will now be available to penetrate into the sea, where it will allow the water there to heat up even faster. No doubt some of that excess heat will lead to increased evaporation and precipitation in the Arctic, and some will be transferred into wind and ocean currents and transported elsewhere. It is possible that convective processes may allow some to be transferred to greater depths.

As for your question regarding the coupling of the energy budgets of Northern and Southern hemispheres, I do not know. I suspect there is some sort of heat exchange between the two hemispheres, but I am not aware of the mechanisms involved, or even if they have been studied to any great extent. Heat energy will flow into cooler areas, one way or the other, but I expect the primarily oceanic composition of the Southern hemisphere will make the process there more stable and gradual than in the North.

However, I do suspect those mechanisms will be changing in new and unexpected ways as the increased heat retention in the Arctic Ocean becomes established and continues to increase.

No one really knows exactly what will happen. But we can be certain SOMETHING will happen. Its severity, and timescale is still a matter of great debate and confusion (as you have probably noticed if you have been following these comments for any length of time). I, personally, do not find this reassuring.

[David Nemerson]

I googled "Latent heat of fusion arctic ice melt" Here are a few hits:

http://www.occupyforanimals.net/how-the-climate-will-change--the-role-of-latent-heat-of-fusion-in-global-warming.html

http://arctic-news.blogspot.com/p/latent-heat.html

and:
Latent heat is a factor, but is completely eclipsed by the rate of global warming. For example, since 1978 the April (maximum) Arctic sea ice has decreased in volume by about 11000 cubic km. The latent heat absorbed by the ice to achieve this is about 3.7 x 10^^18 Joules. Compare this to the amount of excess heat, which has been absorbed by the oceans, which is about 2.0 x 10^^23 Joules per decade. That is, some three to four orders of magnitude more heat than the decadal heat required to melt the Arctic ice. Of course there are complications of the heat absorbed by land (much less than in the oceans), melting of Greenland and Antarctic ice sheets, and uncertainty over the depth of oceanic warming, due to sparsity of measurements, especially in the southern hemisphere. But however you cut the statistics, the latent heat is minuscule compared to the planetary heat imbalance.
http://earthscience.stackexchange.com/questions/6527/is-global-warming-being-moderated-by-latent-heat-of-melting-polar-ice

[Al Rodger]

David Nemerson,
I think your reference must have dropped a decimal point shift somewhere in their calculations. I find the bottom paragraph of the PIOMAS page is always very useful in remembering the energy required to melt sea ice. It's about 3,300 cu km per zettajoule (zetta=10^21). So 11,000 cu km would require something like 3.3 x 10^21 j. It doesn't affect the conclusion but it is a significant correction.

[Bill Fothergill]

@ David N,

I get the same as Lodger.

Latent Heat of ice ~ 333.55kJ/kg

Density of sea ice ~ 910 kg/cubic metre

Energy to melt 1 cubic metre (no temp change)
~ 303,531 kJ

Energy to melt 1 cubic km ~ 3.04E+14 kJ

Energy to melt 11,00 cubic kms ~ 3.34E+18 kJ

(Bloody hell - it was 45 years ago I was doing this kind of stuff in 2nd Year Thermodynamics.)

[Bill Fothergill]

@ Geert "... if in a few years no ice will be left over in the arctic to melt ..."

Geert, it would be interesting to know what prompted that question. If you read somewhere that there would soon be no Arctic sea ice, could you please provide a reference?

Specifically, there is a world of a difference between effectively ice-free conditions at the end of the melt season, and all year round ice-free conditions. It is therefore useful to know what someone means when they talk about there being no ice left.

[David Nemerson]

Assuming your correction is right, it does affect the conclusion, doesn't it? The earthscience link says it would take 3.7 x 10^18 joules to change phase of 11,000 cu km of ice from solid to liquid. You suggest it's more like 3.3 x 10^21. The reference goes on to say that the oceans are absorbing 2 x 10^23 joules per DECADE or 2x10^22 per year. So is the latent heat thing is actually within one order of magnitude of the total amount of excess heat going into the oceans per year? That does not strike me as "minuscule". This calculation would appear to refer to the amount of heat that is no longer devoted to melting already lost ice, not the amount that will no longer be needed in the future contributed by further ice loss.

I'll try and dig deeper into this.

Can someone more familiar with this math weigh in?

[Jim Hunt]

The first article that I'm aware of emerging from the "Arctic Change and Its Influence on Mid-Latitude Climate and Weather" workshop in Washington DC:

https://psmag.com/in-the-shadow-of-trumps-first-week-climate-scientists-gather-in-washington-58d7034b92af

Perhaps unsurprisingly there's a political angle:

The new administration may reject overwhelming findings that heat-trapping greenhouse pollution is tilting Earth’s climate toward possibly catastrophic change, but that isn’t stopping the researchers at the conference from discussing the scientific reality that climate change’s most serious effects could happen much sooner than expected.

Moving on to a bit of science:

Observations from recent years support the idea that the melting ice is a key factor in shaping the persistent pattern of warm temperatures over the Arctic that displaces bitter cold air toward North America and especially Eurasia, says conference co-chair Judah Cohen, a climate scientist at the Massachusetts Institute of Technology.

Judging from the Twitter feed not everyone agrees!

[Bill Fothergill]

David,

The mathematics is trivial, but I could certainly have made a typing error sticking this into a simple spreadsheet. (In much the same way that I typed "Energy to melt 11,00 cubic kms ~ 3.34E+18 kJ", when that should have said "11,000 cubic kms".)

All you have to do is...

a) check the value I gave for Latent Heat
b) check the density value (N.B. This is approximate, and varies with the age of the ice, and whether it is draft or freeboard.)
c) multiply out as shown in my earlier post

You might want to take a look at the excellent Piomas graphs produced by Wipneus.
https://sites.google.com/site/arctischepinguin/home/piomas

You can see that, over the 1979-2016 period, April volume did indeed drop from ~33,000 cubic kms to a bit under ~23,000 cubic kms. However, by September 2016, volume was under 5,000 cubic kms.

Therefore, the volume lost in the 5 months Apr-Sep last year (indeed through really any Apr-Sep) caused by seasonal processes is nearly double the cumulative 1979-2016 April loss.

[Bill Fothergill]

Sorry, I hit "Post" without actually finishing my train of thought.

The 10,000 or 11,000 cubic km loss of April sea ice was spread over a period of about 38 years. You are comparing the energy equivalent of this cumulative loss to the OHC gain of a single year.

Apples and oranges.

[wayne]

oversimplified statement, Hi Jim

"over the Arctic that displaces bitter cold air toward North America and especially Eurasia "

What we observe is the lack of cooling to space due to thinner sea ice and more dark ocean inviting Northwards Cyclones to persist over the entire Arctic Ocean. This changes the entire Arctic circulation pattern favoring stronger cooling over the northernmost continents during winter, this greater cooling favors more injection of heat Northwards , because to the East of the Colder land zones is a bent jet stream aiming towards the Pole coinciding where the heat source is, the oceans.

Bill , grrrr , you are not going to be complete without further work.

Not finished, I think Gavin or Tamino calculated solar insulation heat number, and it was potentially sufficient to melt everything,
I regret keeping it elsewhere, so back to work! :)

Too much emphasis on "no sea ice" , Geert

The New World Order will always have sea ice during winter for centuries, it depends how fluid or rapid it moves about, it moves very rapidly now. We are here, and having no sea ice during summer is not a big deal since we are already here with the weather it potentially gives as described in my first paragraph above.

[Bill Fothergill]

@ Wayne "Bill , grrrr , you are not going to be complete without further work."

Sorry, but I've got no idea what that means. ;-)

Regarding total SI, I had to cover that a few years ago for an astronomy lecture I was delivering. Here's how it goes...

Solar Constant* (measured at TOA) ~ 1,366 watts/sq metre
(*I do cringe at the use - or misuse - of the word "constant" when used in this context. However, it's a pretty standard term.)

Radius of the Earth ~ 6,374 kms

Effective intercept area (Pi x Rsquared) ~ 1.28E+8 sq kms

which equals 1.28E+14 sq metres

Total solar power hitting TOA ~ 1.74E+17 watts

Effective power (albedo 0.3) ~ 1.22E+17 watts

Number of seconds per annum ~ 31.5 million

Total solar energy entering Earth system...
~ 3.84E+24 Joules per annum

"... The New World Order will always have sea ice during winter for centuries ..."
Absolutely agree - but there are quite a few on Espen's IJIS thread on the forum who subscribe to the "winter ice will be gone soon" bollocks.

[Andy Lee Robinson]

PIOMAS just released - shocking figure for January.

Please RT!
https://twitter.com/ahaveland/status/827698233426243584

[wayne]

Bullocks is right, Hi Bill

Now given no clouds say 70 N latitude solar insolation from May To September may be just enough to melt how many cubic Km?

Thanks for the calculation presentation,

because, it will determine the summer when there will be no more sea ice. So where are we at? Just now, does the sun have enough rays to melt everything? Factor then the clouds 40% insolation reduction. And we will know.

"3.7 x 10^18 joules to change phase of 11,000 cu km of ice from solid to liquid. "

Seems to me we may have enough at an x cubic kilometer number.
Have we reached this 'x" number?

[Paddy]

Barely more than half the volume in 1979... And based on recent previous years, this would predict a max volume of about 21k (if the freezing season actually gets back to normal volume generation). Pretty scary.

[wayne]

Let's find "x"

66.23 N latitude northwards till the Pole, theoretical joules given
40% cloud cover, precluding ocean temperatures.

Total Earth Joules per annum =3.84E+24 joules

sun radiation input for 5 months = 6.40E22 joules

multiply by .6 , 40% cloud cover = 3.84 E22 joules

divide by 9 size of Earth/area of Arctic = 4.27 E27 joules

times by .8 arctic ocean area = 3.41 E21 joules

Piomas Maxima 21,000 cubic kilometers sea ice melts with = 6.38E15 joules

Obviously these numbers need refining, particularly Arctic Ocean land ratio, solar radiation input at low sun altitudes. So “x” is not found yet.

[wayne]

divide by 9 size of Earth/area of Arctic = 4.27 E21 joules

[Bill Fothergill]

@ Andy LR

Your "Death Spiral" keeps looking more and more terminal, doesn't it?

The NSIDC monthlies came on line yesterday, and they were a harbinger of what PIOMAS was going to say.

Average January area in 2017 was 16.7% down on Jan 1979. Given the fact that average thickness has also gone down by ~ 1/3, there is no real surprise in the PIOMAS number - just continuing horror.

Incidentally, although NSIDC had Jan 2017 down 3.7% on Jan 2016 as regards area, the equivalent "decline" in extent was barely half of this, at just 1.9%.

This serves to add more weight to the argument, put forward by Wayne and many others, that extent is becoming less and less meaningful as a genuinely predictive metric.

[Jim Hunt]

Wipneus' gridded PIOMAS thickness is out now also. All that and much more at:

http://GreatWhiteCon.info/2017/02/facts-about-the-arctic-in-february-2017/

SSW + WACC conjectures aside, there's plenty more anomalously warm air heading for the Arctic Basin as we speak.

[David Nemerson]

Thanks Bill. I realize the arithmetic is trivial; it's really the thermodynamics I'm trying to wrap my head around. Geert, above, basically asked if the latent heat of fusion is a big deal in the arctic, or not.

You are completely correct in pointing out that comparing the latent heat embodied in the 10 or 11,000 cu km loss in summer volume minimum over the past decades and the excess heat stored in the oceans in one year is apples to oranges. I'd go one further and say that comparing the dynamics of latent heat in the arctic to long term storage of the mounting global energy imbalance (mostly in the oceans) is a pretty meaningless way of looking at this issue.

I did look at Wip's graphs and went ahead and downloaded the data. According to PIOMAS, the total volume of ice created and then melted every season hasn't really changed that much. It is generally in the 15-18,000 cu km range every year and has actually increased a bit in recent years. So, during recent melt seasons, if anything more energy is being "spent" on the latent heat of fusion than earlier in the record.

So, my, and I think Geert's question is, as this stage of the arctic's decline transitions into one where there is just less ice to melt each year, and less energy is needed to change phase, will that have a big impact on the energy budget in the arctic?

For the sake of argument, let's imagine an upcoming season where the max is low enough to melt out by, say July 1 (even if there is still some vestigial ice around the CAA or whatever). Will the fact that no energy will need to go into melting for the remainder of that season have a big impact on the energy budget? Is this effect swamped by albedo for example?

I apologize if the answer to this is well known. There does appear to be some serious handwringing on the web about the problems this will cause. Thanks.

[zebra]

David,

I just want to remind people that when the water freezes, it gives up the energy.

So perhaps you could refine your question a bit more in terms of what you mean by "energy budget"?

[David Nemerson]

Zebra, Geert asked "Hello there, I am wondering what will happen if in a few years no ice will be left over in the arctic to melt... the heat that now goes into the ice to melt it, must go somewhere else like the sea itself and I am wondering if models have taken into account the extra accelleration (feedback) this will bring about in the rising of arctic and global temperature rise... this must be, I guess, a big contributor to extra heat absorption in the oceans..."

If the same amount of ice melts as freezes every year, the equation is balanced. I get that. And that's why I pointed out that while the ending volume is now less than it used to be, the annual flux is about the same.

What you seem to be saying is that there is no net effect whatsoever. You can freeze and thaw a lot of ice every year or no ice every year. Energy in, energy out, no difference. And that makes intuitive sense.

When you hear people say things like "Once the ice all melts, all that energy that used to go into melting ice will go into heating up the system" that's fundamentally wrong? Yes, we got rid of a few thousand cubic kilometers of ice over several decades and that had some fairly small effect on the energy balance of the planet, but there is no looming feedback whatsoever. Right?

[zebra]

David,

Oh gosh no-- I worry about all kinds of looming feedbacks all the time! (seriously) :^)

But also seriously, I am just trying to help with people organizing their thinking and understanding what their questions (really) are.

The thermodynamics of various scenarios, like low-ice summer, ice free summer, low-ice winter, ice-free winter, is each a long discussion in itself. So, choosing one is the first step.

Then, you first ignore all the mechanical dynamics (transport by currents and winds, compression, and so on) that these guys have been discussing for years.

And the possible changes in weather patterns, also put aside.

Now, even with that, do we have a simple model? No, as, again, these guys have discussed over the years, ice reflects but ice retards radiation, more water vapor less water vapor, low clouds high clouds, yadda yadda.

This is why scientists specialize, and within the specialty work with narrow hypotheses.

So, exactly what was your question again?

My experience tells me not to dismiss concerns about low-probability but high-consequence phenomena. I've never met a complex non-linear system to which you can keep adding energy and expect a good outcome.

[Elisee Reclus]

Thanks, Zebra. I needed that.

[David Nemerson]

Yikes, thought I was pretty clear! Someone else else here posed a question: "Hello there, I am wondering what will happen if in a few years no ice will be left over in the arctic to melt... the heat that now goes into the ice to melt it, must go somewhere else like the sea itself and I am wondering if models have taken into account the extra accelleration (feedback) this will bring about in the rising of arctic and global temperature rise... this must be, I guess, a big contributor to extra heat absorption in the oceans..."

Answering this is pure physics. No complexity required! No ice movement, no questions about when high, when low. None of that! No new water vapor and storminess regime. Nada! Just looking for some simple confirmation.

The energy required to change phase from solid to liquid is returned to the system when the liquid refreezes. In a given year the enthalpy of phase change is balanced as long as the melt and the freeze are equal. But, the size of the ice cube IS shrinking and will continue to shrink. So my question is, does this statement make sense?: "Once all the ice is gone all the energy that used to go into melting ice will go into heating water and the rate of arctic amplification will accelerate."

It seems to me it does not. The ice cube has melted over a period of decades and there is nothing magic when the last little bergy bit goes. There is no discontinuity there. The energy that it took to melt the ice over decades is just part of the ongoing and increasing energy imbalance of the planet and has all already been accounted for.

There are tons of posts on the interwebs saying things like "Oh my god, the amount of heat required to melt a gram of ice will increase a gram of water by 80 times as much (or is it 160x)! Once the ice melts were screwed!" This is BS. That's all I'm trying to confirm. Because Geert asked!

[zebra]

David,

Look, I don't think anyone really intended to ask about "the last little bergy thing"-- it is just imprecise, hyperbolic, language, which is what I try to fix from time to time. I think they were thinking about one of my scenarios, where we are really talking about two alternative realities, with all else held constant:

A. No summer ice.
B. The original amount of summer ice.

Of course, in the first order approximation, for A the energy will go into creating water vapor and into the water, raising the temperature.

So, putting aside whether "feedback" is the correct term for this particular instance, the original question isn't grossly foolish.

But I repeat-- the reality here is simply not simple. Between A and B, if you are predicting say a yearly average temperature, I would not place a bet using only my (pretty good) physics intuition.

[Andy Lee Robinson]

Fortunately David, we have science to quantify reality instead of relying on a simplistic notion based on how something might "seem".

Once all the ice melts, it can no longer act as a buffer to clamp the temperature, and owing to reduced albedo, the temperature of the ocean *will* rise at a dramatically higher rate.

This is not speculation or "BS", this is physics. The energy cannot be created or destroyed, and if it can't radiate away, or be absorbed in changing the phase of a substance with an extremely high specific heat capacity, then the waters must heat up.

The conditions of the experiment change as it continues on what becomes essentially a different planet.

[wayne]

My calculations need to be corrected or reviewed:

number seconds for 5 months = 13.15 million
rough arctic sea ice area = 12.2 million km square 1.22E13 m2
Top of Atmosphere Arctic solar constant April to September average = 300 watt/m2
Ocean Insolation Arctic summer = 4.79E22 joules
40% Albedo/clouds reduction X .6 = 2.88E22 joules

So far I have a lot more sun energy needed to melt everything,

x is 94,630 km3 way more sea ice than at present, calculation needs refinement

[David Nemerson]

Wow, Andy, I don't think you read what I wrote at all. Obviously "Once all the ice melts, it can no longer act as a buffer to clamp the temperature." That's not the question and your statement about "we have science" is pretty condescending. I'm a PhD biologist and I asked a sincere question. I specifically asked about the effect of albedo as it is my understanding that that is what will drive increased arctic amplification, NOT the fact that incoming energy will not longer be devoted to the extra energy needed to change phase from solid to liquid. As I have repeated every time I've brought this up, a poster above asked specifically about the issue of the latent heat of fusion. And I have said that I have read in many places that "once all the ice melts all that energy the used to overcome the latent heat of fusion will now go into raising the temperature." That's a totally different thing than "dark oceans absorbs heat (albedo)."

I am certainly not engaging in hyperbolic language. But the first link - the first Google hit - does have this language:

"By now, any reader still with me will have concluded that this cooling will be short-lived, and we are currently enjoying the maximum of its cooling effect. Although the ice will continue to melt faster and faster, it's total amount will continue to dwindle, and the amount of LHF absorbed will decline, eventually to zero when there is no ice left. At that point, because there is nothing left to absorb the quintillions of calories in LHFs, global warming speed will take a quantum leap, as if someone had cranked the dial to 10."

All I'm saying is THAT seems hyperbolic to me. This is a continuous process. There is not some point in time when suddenly the "needle goes to 10" because there is zero ice left. This seems pretty straightforward to me. And I think that's what Geert was asking about.

I wasn't saying that the increased albedo won't increase arctic amplification! Geez.

[Bill Fothergill]

@ David N

Multiples negatives in the same sentence can often be confusing - even for the author. When you wrote "... I wasn't saying that the increased albedo won't increase arctic amplification!"
I think you meant decreased albedo.

(At least that's what I hope you meant. If not, then I'm really all at sea.)

Personally, I'm still hoping Geert will clarify the meaning and provenance of the claim that "... in a few years no ice will be left..."

[Andy Lee Robinson]

I apologize if I came across as condescending, but I'm fairly weary after years of dealing with thousands of climate deniers.

"There is not some point in time when suddenly the "needle goes to 10" because there is zero ice left. This seems pretty straightforward to me."

On what do you base your assumption?

Take a pan of iced water.
Insert a thermometer.
Place on stove and heat.
Observe temperature over time:

T↑ _________/
   t→

You will see a temperature curve like this with a definite inflection once the ice has melted.

Why would the Arctic behave any differently?

There are synergistic effects in play:
1. a decrease in albedo leading to greater heat absorption.
2. a concomitant and accelerating decrease in ice volume as a result of the greater energy available to melt the ice, leading to lower albedo, back to 1.
3. Increased evaporation leading to increased trapping of heat.
4. Changes in ice type and structure changing albedo, wind resistance
5. Increased mobility of the ice as it loses mass and cohesion with potential to be flushed faster "down the Fram"
6. Increased vulnerability to wind and waves encouraging greater mixing with deeper warmer water.
7. Increased algal growth further reducing albedo and increasing heat absorption.
8. Greater chance of precipitation falling as rain which can transfer an enormous amount of energy for melting.

These are only some of the things that come to mind, and they are codependent.

It is clear to me, that when the ice goes, surface water temperature *will* rapidly increase. Why wouldn't it?

Consider this: In summer, the Arctic receives more solar energy per day than Florida.

The only things that would prevent a complete melt out in the next few years would be a drastic reduction in CO₂ and/or particularly cloudy weather in May/June/July preventing the melt from running away.

If we have another summer this year like 2012 then we'll have a new record minimum for sure, and if we have one or more great cyclones like in 2012, then we are staring at the possibility of an ice-free Arctic this year, and your intuition may be tested.

I hope we never find out, but it looks as if we should know in a decade or so.

[David Nemerson]

Gah - Bill you are correct! As albedo decreases energy absorption will increase. You are not at sea.

Yeah, sorry we're flogging a dead horse here. I'm not not questioning the death spiral in way and expect close to a full melt out in the next few years save for a few vestigial holdouts (although the placement of the thick ice above the Fram right now suggests that any hold out will be pretty small).

I also agree that once all the ice is gone, arctic amplification might well run away. I was only trying to gain some clarity and improve my understanding of how this issue of the enthalpy of fusion plays in. Andy, the loop you present includes a host of factors but doesn't even mention the fact that the same amount of energy needed to change the phase of a gram of ice to water will raise that gram of water 80 degrees. I guess that's basically an acknowledgment that the arctic is NOT a pan of ice water being steadily heated from below (which I'm well aware will behave as you say).

So, my intuition is completely in agreement with yours, given all the factors you name. What I'm (still!) less sure about is how important the latent heat of fusion of ice to liquid water is in the overall dynamic.

[Elisee Reclus]

My intuition tells me either the average Arctic September sea ice extent record low, or the minimum ice extent record for September will be broken this year, but probably not both. But the Arctic will not be ice free this summer, and it probably won't be for another decade. As far as ice free for an entire year...probably not before the end of the century.

I can't justify this quantitatively, but I am convinced that a lot of very valid mental processing goes on at the subconscious level, and I have learned to trust my intuition.

Remember, the definition of intelligence is the ability to make the right decision when not in possession of all the necessary data, and without a full understanding of all the processes involved. At least, most of the time.

[wayne]

Elisee

Intuition is good along with calculations:

number seconds for 5 months = 13.15 million
rough arctic sea ice area = 14.1 million km square 1.41E13 m2
Top of Atmosphere Arctic average solar constant April to September average = 400 watt/m2
Ocean Insolation Arctic summer = 7.37E22 joules
90% Albedo/clouds sea ice albedo reduction X .1 =7.37E21 joules

This makes 24,325 km3 should melt every summer.... Is a little better estimate..

Now I wait for anyones refinement..

[Tor Bejnar]

What happens with the pan-on-the-stove experiment when the pan is elongated, the ice is thicker at one end (and prevented from migrating), and the heat is applied near the thinner-ice-end? Will not the ice closest to the heat source melt first, and the ice-less water at that end warm up a little bit while the water under the ice remains cold?

(As a kid, I remember not believing one could boil water in a paper cup without the paper burning, so I put a propane torch under a paper cup and heated it to boiling. It turned out the heat caused a pin-sized hole in the bottom of the cup, but the water did boil (to my amazement). My conclusion: the science said the paper would not burn through, but in real life it did a tiny, measurable, bit.)

In the Arctic last summer, I understand the Beaufort Sea warmed some after the ice melted (or, early in the melting season, blown toward Siberia) while ice remained further north. The year all Arctic sea ice melts, I expect the surface temperature of the Beaufort Sea will be warmer than at the center of the CAB. How much warmer will it be? What will the conditions be five years later?

[Tor Bejnar]

(My wife 'took over' my Facebook, and that is her lovely mugshot.)

[zebra]

David Nemerson,

Just to clarify-- I did not intend to say that you were the one using imprecise and hyperbolic language, rather that you were interpreting others' such usage literally.

So, I am attempting to "translate" and create some focus-- for Geert as well, who may or may not really think that the presence of a single ice cube in a vast ocean would be holding back a massive state change. I doubt he does; I think "when all the ice is gone" is just a way of expressing my A v B dichotomy, or mentally compressing the decades between now (lots of ice) and then (no ice) into a single step-change.

I even doubt that whatever sources you are citing believe that, although sound quantitative thinking surely is in short supply these days. I have no problem calling BS on people, but a little gentle correction seemed more appropriate in this case.

[Elisee Reclus]

Wayne--

A few calculations and some simple algebra always seem very convincing, but the problem is that we are dealing with a very complex and subtle system festooned with feedback loops both positive and negative, and a host of unknowns and uncertainties--and reasonable but unjustified assumptions and approximations.

And then there are the ambiguities. For example, solar insolation varies widely with time of day, time of year and latitude. Shouldn't there be a time-variant cosine theta term in there somewhere? "averaged between April and September" leads to a lot more questions than answers.

Besides, my sources (RASC Observer's Handbook) give a value of 1.37kW/m^2 for the solar constant (at the top of the atmosphere, normal to the Sun). How can it be 400W at high latitudes, even at noon? Am I missing something?

I'm not accusing you of making things up, or even of being mistaken, just that a few simple powers-of-ten multiplications leave out a lot of very important details.

Perhaps a few straightforward calculations can delude us into thinking we have a greater understanding of the processes involved than we really do. The calculations are easy, we can automate those nowadays. The data we enter is still highly dependent on definition and interpretation.

If it were that simple, we wouldn't need this forum, or any science beyond high school physics, at all. We'd all just scribble out our results on the back of a cocktail napkin and push it across the bar.

[Bill Fothergill]

@ Elisee "How can it be 400W at high latitudes, even at noon?"

Quite easily. For example, please see Figure 6i-3 in this link ...
http://www.physicalgeography.net/fundamentals/6i.html

Or ...
http://earthobservatory.nasa.gov/Features/EnergyBalance/page3.php

The obliquity of the planet is currently around 23.4 degrees (and dropping). Therefore, at the boreal summer solstice, the elevation of the sun at the North Pole will be equal to 23.4 degrees.

The intensity of incoming radiation goes as the sine of this solar elevation angle.

Sin 23.4 deg = 0.397

Therefore, using the Solar Constant value I gave yesterday (1,366 watts/sq metre), the intensity of the solar radiation at the NP would be about 542 watts/sq metre.

[Elisee Reclus]

You're absolutely right. I missed the "k" in my solar flux figure.

I stand corrected. Thank your for taking the time to set me straight.

[wayne]

Thanks Bill,

The number in question is taken off a graph from NASA no less, is rough and needs perfecting. I am comfortable with 400 watts/m2 spanning 5 months.

There are good sources of information about my calculations Elisee,

I did mention that it needs perfecting which can be done in a nanosecond if all the brain power here intervenes.

I currently struggle with albedo, which is complex and simple at the same time. There are mostly very simple (yet complex) constants we can deal with, what is left is albedo, which is 90% with sea ice and snow, 50% with bare sea ice:

https://nsidc.org/cryosphere/seaice/processes/albedo.html

but if we mix clouds perhaps 90% is the right number. Latent heat does affect as well but not substantially as far as I can tell. But I come up with x= 24,000 km3 which is likely too much, because there would be open water each summer regardless of atmospheric chemistry. So I wait for guys like Bill to perfect the equation.

[wayne]

24,000 may be good if we consider sea surface temperature -2 C. Sea temperature interaction is step 2, because the ocean has largely its own system going.

[Elisee Reclus]

The illumination geometry and energy flux and physical properties of materials are straight forward, but variables like cloud cover and convection of fluids are essentially unpredictable. This sort of first order analysis can set constraints at the high and low end, but is of little use once all the subtleties of non-linear convective energy transfers are considered.

But as an earlier poster pointed out (I paraphrase) if you keep adding energy to a system, it is going to heat up.

[Bill Fothergill]

@ Elisee "Thank you for taking the time to set me straight"

de rien

When I first heard about mean daily summer insolation at extreme latitudes exceeding equatorial insolation my response was along the lines of "you must be f***ing joking"!

I had to do the maths to convince myself, and then still wasn't convinced - until I had gone through it all again from first principles.

[wayne]

Elisee

Indulge in establishing some basic sea ice geophysical calculations, wait until it is refined, and see if it will reveal something interesting.

[Rob Dekker]

Guys,
I like the calculations based on physical principles, since they tend to give ballpark numbers from which we can finetune.
Let me give you my perspective on insolation in the Arctic, albedo, and what effect an ice free Arctic would have. I find that wayne's 'x' value depends on where in the Arctic you are measuring : At the winter ice edge, the summer ice edge, or the central Arctic.

Let us run some numbers. First off, how much insolation reaches the surface in the Arctic. Here is a good picture of insolation on-the-ground :

https://en.wikipedia.org/wiki/File:Insolation.png

This suggests that (through summer and winter and through clouds) about 100 W/m^2 on (annual) average reaches the surface of the Arctic ocean. That is 100x3600x24x365=3.1 GJoule/m^2/year.

That 3.1 GJoule/m^2 is enough heat (with 330,000J/kg) to melt 9,500 kg on ice per m^2. So if ice were black, 9.5 meter of ice would be melting out over the summer in the Arctic.

In reality, on the summer ice boundary, FYI is about 1.5 meter thick at the start of the melting season, so you already see that the amount of energy that the sun provides is much larger than the energy that finally goes into melting ice. The reason that that (1.5 meter thick) ice does not melt out much faster is because it is white (albedo). That causes a factor 9.5/1.5 = 6.3 reduction in absorption of solar heat during the melting season. That's the albedo amplification effect of having ice versus dark ocean in the Arctic.

Also, if the Arctic would become ice free, that 3.1 GJoule/m^2 will go to warming Arctic ocean water. Typically over a couple of months of the melting season, that affects only the 'mixed' layer of the ocean, which is something like 20 meters of water below the surface. With 4200 J/kg/C heat capacity, the 20 meter of Arctic ocean water would warm 3.1GJ/4200/1000(kg/meter)/20(meters)=37 C over the course of the summer.

In reality, it won't be that much since that kind of warming will also increase radiation to space, but it give a ballpark answer to one of the questions asked before here on this thread.

In summary, an ice free Arctic will create a whole different climate up North, and over the Northern Hemisphere.

[Bill Fothergill]

Nice one Rob.

However, there is a horrible coincidence with the numbers that may need some explanation for those new to this concept.

As you know, albedo amplification can be considered as the ratio between the energy that would be absorbed by a dark surface (i.e. open water) and that which is actually being absorbed at present through a "whiter" surface (i.e. ice, or any snow covered ice).

Mathematically, this ratio could be expressed as...

= [1 - Albedo(water)] / [1 - Albedo(snow&ice)]

Taking the water albedo as ~ 0.05, and the snow/ice albedo as ~ 0.85, that expression becomes...

= [1 - 0.05] / [1 - 0.85] = [0.95] / [0.15] = ~ 6.3

This is clearly exactly the same value of amplification in energy absorption that you provided. The horrible coincidence comes in when this is expressed as [9.5] / [1.5].

1.5 metres happens to be the average FYI thickness mentioned in the same paragraph as your amplification equation, and 9.5 metres happens to be the nominal thickness you said would get melted out over summer in the paragraph before that.

Horrible coincidence!

(There is, of course, a further complication which reduces this idealised amplification ratio. At very low incidence angles, the albedo of open water starts to ramp upward significantly, with a concomitant decrease in the albedo amplification. The maths for handling this effect gets interesting.)

[zebra]

Elisee Reclus,

Here's what I actually said:

My experience tells me not to dismiss concerns about low-probability but high-consequence phenomena. I've never met a complex non-linear system to which you can keep adding energy and expect a good outcome.

And I think everyone would agree that an ice-free summer Arctic would change important characteristics of the Arctic sub-system.

But, what we don't have, because of the complexity of the global system, is a clear picture of how correct Rob's last sentence in his last post really is, even with his calculations.

I would be interested in hearing, as a first step, how those with more detailed knowledge would address the A/B question I passed on earlier: Given the changes in the freezing season that would exist, would we indeed see a (much) higher yearly average temp.

By the way, speaking of intuition, I always assumed that summer insolation was greater than, or at least in the same ballpark as, at the equator. Why would all those birds fly North otherwise?

[wayne]

That is very interesting Rob and Bill

I like the 6.3 albedo reduction number, but before accepting this

100x3600x24x365=3.1 GJoule/m^2/year.

I would change the 365 with 182.5, there is no sun during the long night:

100x3600x24x182.5=1.55 GJoule/m^2/year.

Half infers potential melt 4.75 meters per year

Making the albedo reduction number to 2.3, I rather determine
albedo reduction number for every melt season. But first get consensus on the basic geophysics.

As Bill infers Albedo changes dramatically with sun angle , but also on sea ice not only water. Therefore like 2007, when very thick sea ice was hit by highest elevation sun, it went away very fast, confirming largely the suggestion that sea ice is more vulnerable fully exposed to the sun than what we might have thought. However, it is the entire system we must consider, it brings out the definite possibility that summer clouds twinned with sea ice albedo are a big factor, both depend on the presence and absence of sea ice.

[Elisee Reclus]

@ Zebra Re birds flying N.

I'm a geographer, I should have known that.

The Arctic Sun may be lower in the sky, but it stays above the horizon a lot longer. The growing season is shorter but the days longer, which is why some boreal counties are still major agricultural producers, and why polar environments can be so biologically productive.

This asymmetry may have some counter-intuitive influence on our climate calculations. The question is, how will this increase in summer energy affect events during the long night.

I'm still not convinced our back of the napkin calculations will be very useful (other than establishing a few constraints at the extremes). When you're a hammer, everything looks like a nail.

The reason I keep picking on this point is precisely because I'm afraid something terrible IS happening to our planet, and every time we prematurely suggest a horrific
scenario that doesn't materialize it only gives the denialist community more ammunition to use against us.

[Rob Dekker]

wayne, the 100 W/m^2 is the annual average of insolation in the Arctic. So you should NOT divide that by two.

Thanks Bill. Incidentally, it is not really a coincidence that the albedo difference between ice and open ocean matches the ice melt numbers I mentioned (black versus white ice). The stunning match is another indication that the simple model matches quite closely with reality.

[wayne]

"The question is, how will this increase in summer energy affect events during the long night."

It wont be found by being afraid of fake skeptics, but by dutiful participation in search for the truth.

Surely there should be some documentation out there which calculates the potential sea ice melt strictly considering solar radiation? If not , it is bout time we do this.

So far we have found that there is plenty of solar radiation, likely more enough to melt everything, but the right number, is not yet known. Say we accept a number, from there we have a better understanding of sea ice physics. That is one more step in sharing further awareness to everyone.

Rob

Albedo reduction is key. When there is a lot of ice, a la Nansen, late 20th century , thick enough , 3 meters thick from North America all the way to Russia, potential melt of 9 meters seems too much. The albedo reduction factor is 3. Same sun Earth water. LIkely with a lot more summer clouds, of course as Nansen found, a lot more sea ice. Would be nice to get a correct yearly sea ice solar input average. I suspect the NASA graph has it right and favorable albedo is the monster which makes sea ice be or not.

[wayne]

late 19th of course.

[wayne]

Rob,

Try making a weighted transect from this graph:

https://en.wikipedia.org/wiki/Solar_irradiance#/media/File:InsolationTopOfAtmosphere.png

Can you get 100 w/m2 ?

[Rob Dekker]

wayne, your graph shows top-of-atmosphere (TOA) insolation. On average that is 160-180 W/m^2 in the Arctic, and 80-100 W/m^2 annual ON THE SURFACE according to these figures :
https://en.wikipedia.org/wiki/File:Insolation.png

[Rob Dekker]

Wayne, you mentioned " The albedo reduction factor is 3." and "I suspect the NASA graph has it right".
I am totally open for an adjustment to my albedo feedback number (6.3) as long as it is sustained by evidence.

So based on which info did you conclude that albedo feedback is 3 (and not 6.3) and which NASA graph are you talking about ?