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Neven

Given the weather forecast, the ice might retreat a bit more northwards. Would 87N be possible?

D

Deepening penetration of saline Atlantic water into the Arctic is changing the thermohaline circulation and the transfer of oceanic heat to the polar atmosphere. That's what's really important about the Laptev bite. The salty Atlantic water mixes and sinks to the Arctic deep then flows out of the Fram strait down the coast of Greenland. This water isn't salty enough to compete with Labrador sea water for a place on the bottom but it does compete with Greenland sea water.

We have been watching something historic since 2007. The oceanic circulation is changing.

Bfraser

The PIOMAS graph has been updated for August.

Gerg

The August 1922 DNI sea ice chart is here:

http://brunnur.vedur.is/pub/trausti/Iskort/Jpg/1922/1922_08.jpg

...and in context here:

http://gergs.net/2013/07/more-northern-sea-ice/1920-1939/

The red sea ice markings north of Spitsbergen might even be Hoel's assuming the Norwegians and Danes shared data. The marks indicate clear water extending to about 81.5°N, as do other markings immediately to the east. There was no satellite, and air survey is not likely, so these records are probably from close ship survey.

John Christensen

" It's much wider and further into the pack, further than I have ever seen it go."

Well, on Sept. 1, 2012, the Laptev Bite went further towards the Pole than this year by simple visual difference from open water to the blurred area around the Pole:

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=09&fd=01&fy=2012&sm=09&sd=01&sy=2014

Also, on Sept. 1, 2013, we had open water much closer to the Pole than Sept. 1 this year, only with a small branch of 30% concentration slush ice in the way:

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=09&fd=01&fy=2013&sm=09&sd=01&sy=2014

With regards to level of damage to the ice from the Laptev side, I would argue this year therefore is slightly better than the previous two years, but only slightly, since the starting point of every season only is as good, as where things were left off at the end of the prior season.

Since the Atlantic side of the Arctic has been battered hard for a number of years now, it is not surprising that recovery is very slow here, while it has been more substantial in the Canadian/Pacific side and from there towards the Pole.

Neven

John, everything you write is true. In fact, in 2010, when the ASIB came into existence, there was a significant amount of open water near the North Pole.

But the title of the blog post is: Ever sailed to 85N?

Steve Bloom

"Recovery" is true, Neven? Also, that first link (all I bothered to look at) doesn't seem to support JC's claim.

John Christensen

Hi Neven,

I had used the CT archive, as I either don't know how to search the AMSR2 image archive, or it is not there.
It seems, however, when comparing Bremen maps with other ice concentration maps, e.g. from DMI, that Bremen cuts away low concentration areas (30% or less), which is why I made the note regarding CT showing a small area of 30%. I guess it all depends on the chosen vessel in the end.. ;-)

http://ocean.dmi.dk/arctic/icedrift_anim/index.uk.php

Steve,
I know there is a lot of sensitivity with a word like "recovery", but just look at ice volume for the last day of August for 2012, '13 and '14:

Year KM^3 Y2Y Increase
2012 3932
2013 5574 41.76%
2014 7220 29.53%

The volume having nearly doubled in two years is recovery in my vocabulary.

It still doesn't mean the ice is in good shape, as it was in an extremely poor state two years ago, which comparison to any year prior to 2007 will show.

jdallen_wa

Recovery is a dangerous word, which will be exploited and used out of context at the least provocation.

SIA and Extent are both at or below 2013 levels.

Arctic Ocean heat content continues to rise.

http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/heat_content2000m.png

I'll add, the uncertainty in those values is around +/- 1000KM3. That puts a rather high uncertainty into your correlation of "recovery".

I'd wait a couple more years before adding "recovery" to the adjectives describing ice conditions, and look for further improvements in SIE and SIA as well.

John Christensen

jdallen,

I am sure it will.

'Recovery' depends on the vantage point and my vantage point in the note above was the catastrophic year of 2012.

Adding a few more years in the volume comparison below for last day of August, you see that even last year the ice volume had recovered (sorry, can't help myself here) to exceed the volume of 2011 and 2010, thus having more than restocked what was lost in 2012.

In 2014, the Arctic ice volume has increased over last year by nearly the same increase in volume, getting close to the 2009 level.

But as stated above, the current volume still does not stand any comparison to pre-2007 conditions.

Year Day 243 Volume Y2Y Diff.
2006 9395
2007 6652 -29.20%
2008 7823 17.60%
2009 7235 -7.52%
2010 4838 -33.13%
2011 4607 -4.77%
2012 3932 -14.65%
2013 5574 41.76%
2014 7220 29.53%

Area and extent numbers are similar to 2013, but with average thickness around 1.40 meters compared to 1.10-1.15 meters last year, the difference is significant in ice compactness and quality.

Casting doubts around the validity of PIOMAS data I don't think is helping your case, since PIOMAS is both one of the best models in place to assess Arctic ice volume, and secondly that anyone looking at the trend lines for ice volume at the PIOMAS site, will be left with no lack of clarity as to where we are headed..

John Christensen

Adding a few more years for reference:

Year Day 243 Volume Y2Y Diff.
2001 12431
2002 10975 -11.71%
2003 10439 -4.88%
2004 10157 -2.70%
2005 9543 -6.05%
2006 9395 -1.55%
2007 6652 -29.20%
2008 7823 17.60%
2009 7235 -7.52%
2010 4838 -33.13%
2011 4607 -4.77%
2012 3932 -14.65%
2013 5574 41.76%
2014 7220 29.53%

As you see we had a major drop in volume already back in 2002, then the record-setting drop in 2007 (in Kkm^3), and finally the largest interannual drop in 2010 (in %) followed by additional decline in 2011 and 2012.

While the longterm downward trend has been clear for a long time, you cannot fully explain the 33% drop in volume in 2010 by increase in forcing caused by CO2 increase.

Since these extraordinary drops therefore are partly caused by atmospheric or other factors working to enhance the AGW effect, it will also necessarily be the case that the same factors in the opposite mode will reduce or even for a year or two neutralize the AGW effect.

There is no more to it. We observe the ice and we learn. If the ice gains additional volume in 2015 and then additional volume in 2016, perhaps the PIOMAS team needs to consider either the angle of the trend line or if it should not be linear, but none of this would change the fact that the Arctic sea ice is in decline.

I will stop now, Neven, anticipating your PIOMAS update and comments.

Neven

PIOMAS post will be up tonight, John.

Kevin McKinney

Nice animation, Gerg! Thanks.

Kevin McKinney

"If the ice gains additional volume in 2015 and then additional volume in 2016, perhaps the PIOMAS team needs to consider either the angle of the trend line or if it should not be linear…"

I don't think it's likely unless the gains were awfully big; the preceding numbers were so far below the trend line. What we're seeing now looks more like reversion to the trend, for now at least.

And I suspect that it's rather more likely that we won't see gains again next year.

John Christensen

Fully agreed Kevin.

Chris Reynolds

There are 91 days from 1 June to 30 August (I've not had the chance to update since 30 August), of these 91 days, during 82 days Laptev Sea Extent has been the lowest on record.

Therefore it is safe to say that in summer 2014 Laptev sea has had less ice extent than at any time since 1979.

It could be argued that this was a random event. Strong winds from Siberia opened a polnya in winter, this was then extended during the melt season by ice albedo feedback, resulting in record recession of the ice in Laptev.

Such a view is defensible, but it is too narrow. During June for the period 1980 to 1989 average sea ice thickness in Laptev was 2.07m (PIOMAS), 1997 to 2006 had an average June thickness of little less, at 2.01m (statistically indistinguishable).
However after the crash of 2007, PIOMAS June average thickness from 2007 to 2014 in Laptev had dropped to 1.33m.

So a more accurate assessment would seem to be that the initiation of the record low extent in Laptev was due to a random event, but without the substantial post 2007 thinning there would likely not have been the aggressive expansion of open water due to the ice albedo effect.

Chris Reynolds

Sorry second line should read:

Therefore it is safe to say that in summer 2014 Laptev sea has had less ice extent than during any summer since 1979.

John Christensen

Thank you for the analysis Chris!

However: You are testing for a direct correlation between the NAO value and the summer ice extent.

What I mentioned in my hypothesis (on the SEARCH thread), was that an 'undecided' NAO value would eliminate NAO as a factor, which therefore means that summers where this is the case, it is not valuable for analysis (at least for my hypothesis).
- and it is quite likely my guestimated NAO values for when it has an impact, are quite wrong.

Since you did not find much difference between area and extent data, I did this:

List years since 1979, where the NAO index reached a negative value of at least 2 (strong negative NAO), and then added:

* = Happened during summer, and
# = Resulted in significant CT Area decline

This is what it looks like:
1993: * #
1998: * #
2005:
2006:
2008: * #
2010: * #
2011: * #
2012: * #

Based on this, it appears that:

- Most periods with strong periods of negative NAO occured within the last 10 years, and
- If this occured during summer months, CT area turns sharply towards a negative anomaly either immediately or with 4-6 weeks delay

I would also note that the strong negative NAO during the fall of 2006 fits nicely with the record low CT area reached that same fall.

The big challenge of course is the tremendously short period, but it does look like a pattern to me.

Thoughts?


Chris Reynolds

John,

But again four of the six are in the post 2010 period, and as I showed this period significantly increases the correlation. But in the post 2010 period there has been unusually strong dipole activity (at least in June according to Overland, and more generally in the summer due to the Siberian coastal low pressure tendency and Arctic Ocean/Greenland high). Furthermore in the post 2007 years there is the complication of a drop in thickness, which would increase open water formation efficiency and independent of the NAO cause an increase in summer losses.

So I'm sorry but I don't consider your argument to be strong.

Arcticio

Is there any data pointing at the Transpolar Drift has speed up in recent years?

Jim Hunt

Arcticio - For anecdotal evidence there's the comparison between the "drifts" of Tara and the Fram:

http://forum.arctic-sea-ice.net/index.php/topic,624

Somewhat more "scientific" is the speed with which buoys installed near the North Pole now emerge from the Fram Strait. See e.g. Figure 4 in:

"Sea ice mass balance observations from the North Pole Environmental Observatory"

Chris Reynolds

Arcticio,

Try this conference abstract:
http://adsabs.harvard.edu/abs/2013AGUFM.C54A..05S
"The long-term Fram Strait sea ice area export obtained from passive microwave satellite observations since 1982 shows no significant trend. However, for the last decade 2001-2009 a positive trend in sea ice area export can be observed."

I've emailed you a copy of the paper Jim's linked to. If you don't have it I could send you a copy of the Smedsrud paper, "Recent wind driven high sea ice export in the Fram Strait contributes to Arctic sea ice decline."

Which starts:
"We use geostrophic winds derived from reanalysis data to calculate the Fram Strait ice area export back to 1957, finding that the sea ice area export recently is about 25 % larger than during the 1960’s. The increase in ice export occurred mostly during winter and is directly connected to higher southward ice drift velocities, due to stronger geostrophic winds."

Lack of Fram export is a factor in this year's poor melt season, but I can't put numbers to it. The PIOMAS IceVel files are only updated to 2013 and it's a variable I've never looked at. Wipneus has looked at it though. Mmm, maybe there's a way to infer without IceVel.

NeilT

I must admit I'm having a problem with not challenging the PIOMAS data.

One glaring point makes it for me and I'd like someone to explain to me how PIOMAS is able to do this.

At the end of the winter in 2012, before spring, PIOMAS had a max value of 23.37M. Yet, after attaining a lowest ever value of 3.67M, and after a low start to 2013 with the area eventually reaching very slightly higher than 2012, we get a volume max at the end of winter in 2013 of 23.33M.

Now this is not working for me. For 2012 to have a triple. Volume, extent and area record, then pretty much all of the FYI and some additional MYI must have been lost. We also know that extensive export of older MYI happened in 2012.

It is possible to lose MYI rapidly. But, with similar area, it is not possible to regain MYI in one season.

How does the model explain and justify this?

Because if it's not getting that right, then it's overestimating the volume of ice remaining.

Chris Reynolds

Neil

The rate of ice growth is proportional to 1/thickness. So thinner ice grows much faster than thicker ice. Start off with a lot of open water/very thin ice and you get extremely vigorous ice growth in the early winter.

PIOMAS is just doing what it has been doing with ice volume from 1979 onwards - getting it pretty well correct.

NeilT

Granted, when you lose first year ice.

However how can PIOMAS defend replacing thicker multi year ice with first year ice and then stating that it is virtually the same volume for virtually the same area.

It defies logic.

Chris Reynolds

Neil,

Most of the area is now represented by first year ice, so most of the volume is set by the thickening for first year ice.

Then the thicker ice will thin less over the melt season. So adding that in produces less ice over the melt season, removing it makes more new ice.

As I've already been looking at this. Say you have a surface temperature of -10degC applied for 210 days (not realistic - I'm working on that). For increasing initial ice thickness the growth over those 210 days reduces.

Start Thickening
0.1m 1.35m
0.5m 1.02m
1m 0.75m
2m 0.46m

That's start thickness at day 1, and the thickening over those 210 days from the start thickness.

The simple model I use can be compared with PIOMAS, I've done so for the East Siberian Sea. Working monthly (I only have monthly temperature data). The May 2012 average thicknesses for PIOMAS and for the simple model are:

PIOMAS 2.31m
Monthly model 2.48

The simple model has no snow, so it tends to overshoot.

I've been told by people disagreeing with the slow transition idea that later open water will cause the pack thickness in April/May to reduce.

Delay the transition to sub zero temperatures and the start of thickening until later in the winter. I'm working on temperature adjustment for that but using monthly temperature. Here's the actual NCEP/NCAR temperatures for the ESS and my adjustment based on no ice forming until December.

Actual Adjusted
-0.40 -1.80 No ice
-7.74 -3.00 No Ice
-22.46 -9.00 No Ice
-28.55 -14.00 *
-26.66 -26.66
-29.33 -29.33
-24.41 -24.41
-12.97 -12.97
-3.12 -3.12

And by May the thickness is 2.44m, similar to when PIOMAS and the simple model are run with 2012 profiles.

In the ESS during autumn surface temperatures for month N+2 show little correlation with month N, even after a large perturbation like 2012.

In 2012 ice growth in the ESS had started by October.

NeilT

Sorry I hope I'm not being dense here. But I said that over 1M sq km of extra ice melted out in 2012. Predominantly older MYI or > the 2.4m thickness you are stating here.

If that ice was even only 0.5m thick that would mean 500,000 cubic km less ice volume than melting the same volume of FYI.

So what are you saying? That the extra 460,000 cubic km of ice reported by PIOMAS for the high in 2013 (2013 was reported as 40kcukm less than 2013 at max), was created by extra thick FYI created by extra cold temperatures?

Because as I remember it, it was late formation followed by over average warm temperatures followed by an early breakup in 2013.

Not quite the conditions I would have expected to re-create the postulated half a million cubic km of ice lost by the loss of an additional 1m sqkm of MYI in 2012.

I see what you are saying but I don't see how it relates to the sudden replacement of MYI, in one season, with FYI, to re-create almost the same volume start as 2012.

It just doesn't work for me unless we are saying there were exceptionally cold conditions which created significantly thicker FYI than was seen in 2012.

Your own statement was "And by May the thickness is 2.44m, similar to when PIOMAS and the simple model are run with 2012 profiles". If it's the same thickness to replace older thicker ice lost in 2012, then it's impossible for 2013 to have started with the same volume as 2012.

Unless I'm missing something obvious?

NeilT

That should have read "If that ice was even only 0.5m thicker"

Chris Reynolds

Neil,

The statement regards thickness was related to a tag onto the reply to you about people claiming that later open water will mean less winter ice, I'm just saying it is not necessarily so.

The critical issue is that thicker ice thickens far less than thin ice or open water forming new ice.

Hence the following:

Start Thickening
0.1m 1.35m 100%
0.5m 1.02m 75%
1m 0.75m 56%
2m 0.46m 34%

That is to say, 0.1m thick ice at minimum in September leads to 1.35m growth (with constant -10degC surface temperatures), whereas for 1m thick ice in September the thickening is around half of that, 0.75m. These are for the same temperature of -10degC, nothing extra-cold needed.

Using whole Arctic volume.

Year.April...September
2011 22.7 4.3
2012 23.4 3.7
2013 23.3 5.4
2014 23.1 7.2

So what you are saying is that after 2012's September minimum the ice grew back by April 2013 to almost the same volume as in April 2012. Then with more second year ice after summer 2013, the April 2014 figure was still around the same.

What I am saying is that even with the different minimums of 2011 to 2013, most of the area involved is going to be virtually first year ice, in all of thos years end of season extents in Beaufort round to Barents was such that those seas were virtually sea ice free. So most of the thickening was to thermodynamic levels, call that around 2m (although it varies across the seas).

However within the Central Arctic is where you find most of the different thicknesses of ice and hence most of the volume difference in September, because almost all the other seas had melted out.

The Central Arctic winter extent is around 4.45M km^2. The Artic Ocean extent is around 10.2M km^2. So within the peripheral seas over half the volume is set by the thermodynamic growth from open water or very thin ice. Then within the Central Arctic the thickness/growth relationship takes precedence because by September that is where the thicker ice is.

You may have noticed that when I reposted the initial thickness/ thickening figures I put a percentage agains each one. For thin ice in the peripheral seas (or periphery of the central Arctic pack), say around 50cm, the thickening is 75% of what it is for open water (the 0.1m thick initial), but for 1m thick you're only getting half the thickness, or volume, increase. And for ice around 2m the volume gain is only about 1/3 of what it is for open water.

So add more thicker ice at the end of the season and this thcker ice (within Central region) only accounts for volume gain in under half the Arctic Ocean, and then, the thicker the ice is the less it contributes to overall volume increase the following winter.

So that is how I would explain the apparent incongruity of recent volume minimums as judged against the maximums that follow.

NeilT

Sorry Chris, this is not what I'm saying.

"So what you are saying is that after 2012's September minimum the ice grew back by April 2013 to almost the same volume as in April 2012. Then with more second year ice after summer 2013, the April 2014 figure was still around the same."

I'm saying that in the winter of 2012/13 the Area of the ice grew back to almost the same as it was when the 2012 melt season started.

BUT.

That Ice, of the same area, was not of the same consistency. It was 1mkm^2 more FYI than at the beginning of the 2012 melt season.

So how could it be only 40kkm^3 less than 2012.

Where did all that extra volume come from?

It really is as simple as that. I don't understand. I'm willing to learn but I can't see any way that 1mkm^2 of FYI can create the same volume as 1mkm^2 of MYI.

It doesn't make sense to me.

Chris Reynolds

Sorry Neil,

I'm doing a really poor job of understanding and/or of explaining.

When you say:

"That Ice, of the same area, was not of the same consistency. It was 1mkm^2 more FYI than at the beginning of the 2012 melt season.

So how could it be only 40kkm^3 less than 2012.

Where did all that extra volume come from?"

I read it as more or less what I outlined (as you quote in the comment above) and my answer is the same.

Maybe I'm tired. I'll think about it over the next few days. With a bit of luck someone will read this exchange and reconcile us.

NeilT

Thanks for all the time you've put into this on my behalf already Chris. I can't think of any better way to explain it myself either and I'm consumed with discussions on the Scottish independence referendum at the moment.

The Yes poll lost me €90 on my last pay which was paid in € into my UK account....

I'll check back in a while.

D

https://www.yahoo.com/travel/breaking-the-ice-northwest-passage-is-opening-up-to-97140115067.html

I saw this and thought of this post. This is one cruise I'd be really interested in going on. I don't have a spare 20,000 though.
Do you think these sorts of cruises would help by drawing more attention to the Arctic? Or would it hurt by being just another environmentally questionable activity?

D

NeilT-
The ice did not recover more quickly the first 3.5 months of the freeze season in 2012. At the start of 2013 it was still comfortably in record territory. From January to mid-March it set a record for refreeze though. Why the late spike? It wasn't temperature. For the first 2/3rds of that period it was warmer than average, and colder the last third.
The most likely explanation is significant storms. Just like a storm in summer will cause greater melting due to mixing, a storm in winter will cause greater freezing. You probably remember that this was the time that many people in this forum were following the large ice cracks. Also, the Piomas thickness chart showed that the ice had been heavily pushed to the east that winter.

D

The late spike from Jan to mid March 2013 was associated with a strong sudden stratospheric warming in early January 2013. After that sudden warming stratospheric cooling caused strong subsidence over the arctic. A very strong dome of high pressure set up over the pole. This intense high pressure dome was ideal for radiational cooling and ice formation over the central Arctic ocean.

not sure what's happening with the D login.

I'm still FishOutofWater everywhere else, but you can call me George if you like.

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