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Chris Reynolds
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JD Allen, I don't know the answer to your question and yes lateral melt is a concern. However as we've all seen from MODIS and IR, the pack is normally very fragmented - its natural state. So in any mass transport the floes will be broken up and fresh ice will grow in leads between them. The PIOMAS gice data is monthly back to 1979 but the 2015 data is only daily. I haven't yet got round to coding to transform daily into my own monthly files, or to wholly use daily files (which go back to 2000). However we have the Drift Age Model. That's not ideal because it assigns age to the oldest amount of ice with extent (>15%). Anyway the DAM shows more extent of older ice this year than in 2010, this year is more like 2014 or a pre 2007 year. DAM images. ftp://ccar.colorado.edu/pub/tschudi/iceage/gifs/ Week 05 2010. ftp://ccar.colorado.edu/pub/tschudi/iceage/gifs/age2010_05.gif Week 05 2015. ftp://ccar.colorado.edu/pub/tschudi/iceage/gifs/age2015_05.gif
Neven, I didn't mean to imply you'd claimed that FYI meant a pole melt was a certainty. I merely wanted to point out that the FYI state from Siberia to the pole doesn't guarantee a melt out, and past years suggest such an outcome would be unlikely. Sam, For a grid cell's area to be counted towards extent it only needs to have a concentration of over 15%. Let's look at 16.6667%, which would be counted towards extent. That state is 1/6 of area being chunks of sea ice floating in 5/6 of area open water. What you call pulverised MYI is probably thick enough for much of it to last into the late summer. That's when the area only needs to be 1/6 of ice to keep extent up. That really did happen in 2010. http://www.iup.uni-bremen.de:8084/ssmisdata/asi_daygrid_swath/n6250/2010/sep/asi-SSMIS17-n6250-20100901-v5_nic.png The yellow/green stuff in the top left quarter of that plot looked like it would just melt away through August. It didn't.
Neven, Quikscat 30 April 2006. http://manati.star.nesdis.noaa.gov/datasets/QuikSCATData.php (sorry no direct link) Broad swath of FYI from Siberia toward but not quite to pole/ ASCAT 2013 Day 116 (last week of April) http://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2013116.sir.gif Broad swath of FYI to the pole. ASCAT 2012 day 120 (end April) http://manati.star.nesdis.noaa.gov/ascat_images/ice_image/2012/msfa-NHe-a-2012120.sir.gif Broad swathe of FYI to the pole. For comparison ASCAT Day 112 of 2015. http://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2015112.sir.gif Broad swath of FYI from Siberia encompasses the pole. My point is that due to the transpolar drift we have precedent years that had a large expanse of FYI from the Siberian coast towards the pole. I could give other years that aren't as good due to some MYI inclusion. This year the expanse encompasses the pole, but in those other years the ice edge did not even take out all of the FYI available towards the end of April.
Sam, PIOMAS is on track, doing fine, and in my opinion correct. I see no substantive disagreement between PIOMAS and HYCOM. There has been no change to the PIOMAS model since V2.1 was released. Were there such a change I would see it in the data I analyse. The increase in volume as seen in PIOMAS will preclude a crash this year mainly because multi-year ice is being exported into Beaufort and Chukchi. HYCOM shows the MYI tongue is already near Wrangle Island. http://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/arcticictnnowcast.gif On past performance it is likely to make a significant presence in the East Siberian Sea. When I get my coding finished I suspect PIOMAS will back up HYCOM. And for those who don't beleive the models. ASCAT shows the tongue of MYI. http://manati.star.nesdis.noaa.gov/ascat_images/ice_image/msfa-NHe-a-2015112.sir.gif Seriously good melt weather could overcome these odds. But I'm not aware of any predictive patterns at this stage of the year so am not willing to bet on that. I think we're in for another 2010 style year, there is the chance of a good volume loss (if 2013/14 weather isn't repeated), but presence of MYI in the Pacific sector of the Arctic Ocean will probably mean persistent low concentration rotten ice holding up extent late in the summer in Beaufort/Chukchi and the ESS, as in 2010. That alone would smack down chances of a crash. :( Neven and others have observed FYI through to the pole. But due to the transpolar drift it is not the first time we've seen that and it does not guarantee a melt through to the pole. *** On the subject of PIOMAS, PIOMAS gice is the sub grid thickness distribution modelling thicknesses (metres) seen in the legend of the following plot. The plot being a plot of volumes from various gice thickness bands of ice for the Arctic Ocean (Beaufort round to Greenland Seas, Central and CAA). http://3.bp.blogspot.com/-jU1ejjKWOyM/VTlNtbNSXPI/AAAAAAAABwo/-7pzQtFLQoo/s1600/Three%2Bcrashes.png The volume 'crash' years of 2007, 2010, and 2012 are indicated, the plot shows the impacts of those years on thickness distribution within PIOMAS. Wayne, Sorry, been busy writing a blog post, I think we'll have to agree to disagree.
Wayne, 2007 was a weather driven event, how is this relevant? Holland et al 2006, Future abrupt reductions in summer Arctic sea ice finds an abrupt reduction around 2040. However their definition of an abrupt reduction is: "We identify an abrupt event when the derivative of the five-year running mean smoothed September ice extent timeseries exceeds a loss of 0.5 million km2 per year, equivalent to a loss of 7% of the 2000 ensemble mean ice extent in a single year." I have previously blogged in this in 2013. Using data to that year the post 2007 erar does not satisfy Holland et al's criterion. http://farm9.staticflickr.com/8088/8466170382_e52ea07b39_o.jpg At no point does the 5 year running mean smoothed September ice extent timeseries exceeds a loss of -0.5 million km2 per year, the y axis being the 5 year running mean smoothed September ice extent. So 2007 and its aftermath isn't as big as the modelled rapid ice loss events Holland et al discuss. That conclusion is based on data up to 2012, adding 2013 and 2014 would not change it, they would reinforce it. Acretion of ice could happen when the air is warmer due to heat flux into the ice mass which may be colder than both atmosphere and ocean. Existing physics is not contradicted, although this simple model would fail. Yes that model is more simple than reality (spherical chickens in a perfect vacuum). That is why working models factor in more complex processes. However that model accounts for the increase in autumn/winter volume gains seen after 2007, for example in the Central Arctic. http://2.bp.blogspot.com/-0-aWeCO7c-w/VLrQdY9ICRI/AAAAAAAABcc/UQN1YpWj1bY/s1600/Modelled%2BVolume%2BGain%2BCentral.png (Lack of snow and ocean heat flux mean the model grows more ice than PIOMAS, but it still shows a post 2007 increase in autumn/winter volume gain.)
Correction... 'qice' is the flux of energy through the ice driven by the temperature gradient between the ice/ocean and atmosphere/ice interfaces mediated by the thermal conductivity of the ice, it is inversely proportional to the thickness of the ice.
Wayne, The answer to your question is, as Bill explains, 'no'. This is because the very heat release from melting ice is what drives ice thickening. Ice grows due to heat flux through the ice. 'qlatent' is the energy released from ice formation ( as the molecules of water drop from the energetic state of liquid to the less energetic state of an ice lattice they give up energy - latent heat of fusion) 'qocean' is the flux of energy from the ocean. 'qice' is the flux of energy into the ice/ocean interface from the formation of new ice due to the enthalpy of fusion. 'qsurface' is the flux of energy from the ice/atmosphere boundary into the atmosphere. thus, considering net fluxes... qsurface = qice = qlatent + qocean. Incidentally, this is why heat flux from the ocean leads to thinner ice, it takes up some of the flux that would have gone into forming ice through the q latent term. So Bill is correct, the heat produced by net ice formation through the winter does not warm the ocean/ice interface. It is actually driven by the heat flux from warmer ocean to the colder surface of the ice (where the atmosphere is frigid). This relationship between ice thickness and heat flux through it, and basal accretion of ice gives rise to the simplest model of sea ice growth, whose general form can be seen in the core equations of models like PIOMAS and CICE. Although those far more advance models incorporate far more advanced physical modelling of further, more complex, process. I have covered this simple model here: http://dosbat.blogspot.co.uk/2015/01/the-simplest-model-of-sea-ice-growth.html And I have used that simple model to examine the thickness-growth feedback here. http://dosbat.blogspot.co.uk/2015/01/the-slow-transition-thickness-growth.html
Thanks Neven, So the intrusion of MYI into Beaufort/Chukchi is modelled in PIOMAS and HYCOM, is seen in ASCAT, and now in Cryosat 2. Hope for an exciting season looks like residing from Laptev to Barents and towards the Pole.
Toggle Commented Apr 18, 2015 on CryoSat-2 sea ice thickness maps at Arctic Sea Ice
Jim, The ICESat domain is simply Beaufort/Chukchi/ESS/Laptev/Central and can readily be calculated from my regional PIOMAS data.
Toggle Commented Apr 18, 2015 on CryoSat-2 sea ice thickness maps at Arctic Sea Ice
Jim, No problem, I wanted to look at daily anyway - done a few comparisons with the PIOMAS grid box thickness gridded data to make sure my code and comprehension were right. Neven, The PIOMAS gridded data comes out slightly before the 'main series' volume. But I won't have it before the end of the month. That doesn't matter, using the data either Wipneus or I get from the gridded data will suffice. 1) Further motion between now and the end of the month won't draw much multi year ice into the region of the pole - perhaps I should say that is rather unlikely. 2) Now that ice has thickened to around 2m thickness it is a better insulator than thinner ice, so unless there is some sort of exceptionally severe cold snap (again not likely) further thickening should be modest. The thickness profile shown by PIOMAS gice data near the Barneo camp supports what we're all seeing via other methods - first year ice dominant state.
Toggle Commented Apr 13, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Neven, Would that be because of the thickness from the pole to Siberia? I'm not sure how much of a player that will be. As I have the Gice data in front of me (but still only up to December), the years 2011, 2013 and 2014 (December) all look very similar for Laptev and are the worst state since 1979. Jim, Here's the data for the a nearby grid box to Barneo (which may actually be within this grid box). Latitude - 89.25 Longitude - 17.53 Area - 614.7047 km^2 Region - 10 (Central Arctic) Bands GICE Thick Profile 0 3.99E-03 0.00 0.26 3.71E-03 0.00 0.71 1.35E-02 0.01 1.46 0.4950912 0.72 2.61 0.3672681 0.96 4.23 7.55E-02 0.32 6.39 1.37E-02 0.09 9.1 1.11E-02 0.10 12.39 8.83E-03 0.11 16.24 6.75E-03 0.11 20.62 4.54E-04 0.01 25.49 1.18E-04 0.00 Effective Thickness 2.43 Bands are the sub grid thickness bands in metres. GICE is the contents of the PIOMAS data file Giceday.h2015 at day 90 (data packed as single precision), Thick profile is the thickness calculated from the thickness profile (which is normalised to 1). And Effective Thickness is the sum of the thickness profile, this is the PIOMAS thickness value most commonly used. Note that the Gice thicknesses are not really point thicknesses, they are the centres of bands of thickness. The ranges and central figures are from Zhang & Rothrock 2001, A Thickness and Enthalpy Distribution Sea-Ice Model, Figure 2. In Plain(er) English... At thickness 0 the profile is zero - by definition. There is a steep rise to a peak between 1.46 and 2.61m indicative of thermodynamically thickening first year ice. The cut out ice shown in the photo from Barneo looks to fall in the 0.71m category, PIOMAS models a very small amount of this ice. If the Barneo photo is showing typical thickness in the area they are either in a thin area (unlikely), they have (as suggested in my previous comment) chosen a patch they though would be thin, such as a frozen lead, or PIOMAS is modelling ice that is far thicker than reality (due to the nature of thermodynamic growth and recent winter temperatures I consider this latter option the least likely). Looking to thicker bands there is a small but significant fraction at thicknesses from 4.23m to 16.24m. This represents ridged or otherwise mechanically deformed ice. However I am not sure if this is all thickened in situ. The transpolar drift has been reasonably strong this year meaning pole ice is probably from around the Laptev region. But there may be inclusion of some multi year ice. The block shown in the first photo from Barneo might support this interpretation as it seems to be isolated and not part of a ridge. However there is evidence of local ridging in photos 3, 7, and 9.
Toggle Commented Apr 13, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Are those ice ridges in the background? The PIOMAS sub grid thickness distribution is intended to model processes varying between thicker and thinner ice. So the grid boxes around the pole will contain ice that thick, thicker first year ice, and ridged ice. By the way. When looking for ice through which to cut a hole for a diver which would one chose. 1) mechanically deformed first or multi-year ice? 2) first year ice of typical thickness? 3) first year ice that has grown in a lead that froze over a few months ago? Be wary of observational bias. When Excel has finished its current batch of number crunching, I will get 31 March 2015 state for the grid box over the Barneo area N 89°30 / W 020°26.
Toggle Commented Apr 13, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Oops, forget the 'all years except' at the end of the paragraph just before the data.
Toggle Commented Apr 12, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Since there seems to be an interest in Beaufort sea ice... PIOMAS average grid box effective thickness in Beaufort is 2.14m this March, only 22cm above 2013 (1.92m), and thinner than at this time in 2012 (2.45m). However the grid box effective thickness is not the whole story. Within a grid box there is a sub grid thicknes distribution. This hangs on a set of 12 thicknesses. 0m 0.26m 0.71m 1.46m 2.61m 4.23m 6.39m 9.1m 12.39m 16.24m 20.62m 25.49m In other words, even though PIOMAS tells us that Beaufort is an average of 2.14m, there is really apread of thicknesses across the full range of the above thickness points. This data is available in gice files. Now the gice files only have monthly data for 1979 to 2014, and I haven't had the time to convert the daily gice data to monthly for Jan to March 2015. But I have comparable volumes for all of those thickness points for December 2001 to 2014. To keep things simple I have used a cut off to define two thickness bands. The thickness points from 0 to 2.61m contain ice that in December is almost totally first year ice, in fact every year in December shows a peak in the 1.46m thickness band. The thickness points from 4.23m to 25.49m in December is almost certainly mechanically deformed (e.g. ridged) multi year ice. Volumes are in km^3, all years except Year / 0 to 2.61m / 4.23 to 25.49m 2001 577.4 326.6 2002 532.0 183.4 2003 479.1 103.2 2004 585.5 191.5 2005 585.8 310.3 2006 536.9 132.6 2007 492.5 24.1 after the 2007 loss 2008 487.5 91.9 2009 534.2 103.5 2010 507.9 34.1 after the 2010 loss 2011 613.9 86.0 2012 517.4 21.3 after the 2012 loss 2013 505.8 127.2 2014 542.8 112.7 Conclusion: In the PIOMAS model multi year ice fraction in Beaufort is some 20% of total volume. It is a significant increase on 2007, 2010, 2011, and 2012, and is similar to last year. This is along the lines of what HYCOM and the Drift Age Model is telling us. My view - Beaufort will not melt out this summer.
Toggle Commented Apr 12, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Dean, As I had the spreadsheet open I've just done what you suggested. The results are as follows. A = Area Arctic Ocean Basin B = Area All NSIDC C = Extent All NSIDC Periods A / B / C 1983 - 1990 0.080 0.153 0.245 1991 - 1998 0.240 0.299 0.590 1999 - 2006 0.193 0.166 0.370 2007 - 2014 0.293 0.311 0.429
Toggle Commented Apr 9, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Dean, I didn't consider it necessary because the size of the interannual differences for 2006/7 and 2012/12 is so huge and is far greater than any other years in the series. I have uploaded a graph from my spreadsheet here: https://farm8.staticflickr.com/7647/16469614043_19cfd6cdaa_o.png Terms explained in my comment of April 7th. Al, I suspect we both need to wait for more data for something strong to emerge. You might find the above graph interesting.
Toggle Commented Apr 9, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Bill, Thanks for that, Frozen Planet was fine scientifically. What would one expect of a programme fronted by Attenborough? I recall fact checking Frozen Planet at the time just as an exercise in showing Lawson was wrong. Al, GWPF aside. I've looked several times in the last few years at whether interannual variability has increased in Arctic Sea ice. Aside from the drop in 2006 to 2007 and the rise in 2012 to 2013, I cannot see evidence for a post 2007 increase in variability. I've just done the following table up to 2014's data, and your comments have inspired me to try another region (A). The regions/metrics used are: A Area Arctic Ocean Basin B Area All NSIDC C Extent All NSIDC Arctic Ocean Basin is Beaufort/Chukchi/ESS/Laptev/Central I had hoped it would better reflect the loss of thicker ice after 2007. All NSIDC is the whole of NSIDC concentration data. Area and Extent are as usual. Data is for 8 year periods because 2007 to 2014 is an 8 year period. In order the columns are - A / B /C 1983 - 1990 0.149 0.213 0.376 1991 - 1998 0.342 0.411 0.720 1999 - 2006 0.274 0.264 0.477 2007 - 2014 0.526 0.561 0.706 I've calculated the interannual differences for each of the three data series using a late summer extent or area (7 day average centred on 1 September). These are then converted from a series of positive and negative numbers to magnitudes (i.e. I've removed the sign of the numbers using SIGN(X) * X), that allows me to use averages. All three sets A, B, C, show a peak in the 2007 to 2014 period. However this is just due to the drop in 2006 to 2007 and the rise in 2012 to 2013. That can be seen by dropping those years from the data and calculating the above averages again. This is the result. 1983 - 1990 0.149 0.213 0.376 1991 - 1998 0.342 0.411 0.720 1999 - 2006 0.274 0.264 0.477 2007 - 2014 0.293 0.311 0.429 So apart from the two 'oddballs' I find no increase in variability in my definition of late summer area or extent. What I would love is a massive crash this year to add to the oddballs dataset... Thinner ice than in past decades should mean increased interannual variability. I just think it will take some time for the pattern to emerge from the noise.
Toggle Commented Apr 7, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Scrub that last para, it's too late on a Sunday night and I'm half watching Raiders of the Lost Ark. Internal variability could be interpreted as ice dynamics driven changes.
Toggle Commented Apr 6, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Thanks again Frank, just read it. I need to revise my assessment of the GWPF, they're either stupid or mendaceous. It seems they either haven't read the paper (stupid) or assume their target audience won't (mendaceous, although probably an accurate assessment ;) ). The paper starts by stating: "...By deliberately cherry-picking these periods we will demonstrate how using short-term trends can be misleading about longer-term changes, when such trends show either rapid or slow ice loss." The paper is well worth reading. In particular figure 4 is a very useful approach. But I still disagree with the internal variability argument, I think what is going on can be explained largely by sea ice dynamics - but as an amateur sea ice nut, that is perhaps to be expected.
Toggle Commented Apr 6, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Thanks Frank, With it being in Nature and being recently published I didn't think it was worth trying.
Toggle Commented Apr 6, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Jim, Thanks, shame that Swart et al is paywalled. I'm not convinced by the title in respect of the 2013/14 volume increase since that seems to stem from weather in 2013, which I wouldn't describe as 'internal variability'. Given that 2011 was the first year to meet 2007 (new record in some datasets but not in others), and 2012 went even lower, I view 2013/14 as outliers driven by weather and 2011/12 as telling us more direct information about the open water formation efficiency impacts of the 2010 volume loss. i.e. the post 2010 thinning plus the Arctic Dipole typical of all post 2007 years apart from 2011, led to that near record and following record. Al Rodgers, Sorry, but I'm not really seeing what you're saying about 'wobbles', there are wobbles earlier in the annual average lines on your graph. I think the telling graph is the final one on the GWPF webpage. http://www.thegwpf.com/content/uploads/2015/03/Screen-Shot-2015-03-31-at-11.55.21.jpg But they are totally failing to grasp what is going on. As shown by Lindsay & Zhang the PIOMAS volume loss is due to a self-acceleration as a result of ice-albedo feedback. This process commenced around 1995 and continued through 2007. As can be seen from the above graph, taken from Cryosphere Today, the fall in anomalies is most severe from the late 1990s to 2007. The decline in area/extent accelerated shortly after PIOMAS showed the severe drop in volume began. This drop in volume reduced thickness and increased the ease with which a given thinning of ice in spring/summer could reveal open water (open water fomation efficiency OWFE). So as the dropm in volume proceeded extent and area fell, particularly in the summer. The event of 2007 cleared out masses of thicker multi-year ice from Beaufort/Chukchi/ESS and led to an increase in the seasonal range of extent/area. Again this was because OWFE increased, but in 2007 there was a step increase. And the increased summer melt (and responding increased autumn growth), with earlier melt and later growth caused the massive annual variance in the post 2007 anomalies in that graph. Crucially the 2007 event reduced the thickness around the Central Arctic, for example - Chukchi, 2000 to 2006 Sept avg thickness 60cm Chukchi, 2007 to 2014 Sept avg thickness 5cm ESS, 2000 to 2006 Sept avg thickness 68cm ESS, 2007 to 2014 Sept avg thickness 23cm So further thinning in these regions had little effect, winter thickness was already low enough to produce large tracts of open water. This led to a collapse of September area in the peripheral seas of the Arctic Ocean. http://2.bp.blogspot.com/-WPJ2wMuTyaY/VEIJEgIWVGI/AAAAAAAABIQ/-QYv7_7gwr4/s1600/Fast%2BTransition%2BArea.png That leaves the Central Arctic from which to get further gains in amounts of open water in September. But since 2007 we have only seen 2012, where such gains played a large role. And after that we had the increase in volume in 2013 and 2014. So what the GWPF are trying to spin as potentially indicative of a turn-around in the Arctic sea ice is nothing of the sort. What is going on is entirely consistent with the Arctic Ocean undergoing a transition to a seasonally sea ice free state. A process initiated by anthropogenic global warming. Neven, Thanks for the Manabe ref via Bob Grumbine, it goes further back though. Hansen et al 1988, Model Forecasts of Global Climate Change refers (page 9349, col 1, para 2) to a personal communication from Manabe and Bryan regarding their model. From which Hansen et al conclude that the warming in the Hansen model and cooling in the Manabe model (around Antarctica) results from differences in the ocean heat transport. The GWPF really aren't very competent.
Toggle Commented Apr 6, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Bill, 1) Jinlun Zhang (AFAIK, the main chap behind PIOMAS) has run the model on the Antarctic. He's examined the increase in Antarctic sea ice in a 2006 paper, "Increasing Antarctic Sea Ice under Warming Atmospheric and Oceanic Conditions". The gridded PIOMAS data for the Arctic comes from an earlier study into the loss of Arctic Sea Ice, it has continued to be updated because people are using it. The 'main series' of PIOMAS volume from the website is provided because of public demand. Neither of these two specific conditions apply to the runs for the Antarctic, as far as I know, and I am not aware of data for the Antarctic. 2) I am not aware of a metric of ice in ice shelves. 3) Dunno, I only use NSIDC Extent. Neven, I'm now interested in who has been making the claim of a post 2006 stabilisation. It's such a weird conclusion I'd love to see how someone has twisted the data to support it. *** For what it's worth: My prediction for 2015 September average NSIDC Extent is: 5.20 million kmsq +/-0.63 million kmsq. Here are the hindcasts for 1979 to 2014. http://2.bp.blogspot.com/-oxl9bvFaJHA/VSI8bE7XGLI/AAAAAAAABtU/UoITbiSpxpo/s1600/Hindcast.png
Toggle Commented Apr 6, 2015 on PIOMAS April 2015 at Arctic Sea Ice
Jim, Just to back up my last statement: http://1.bp.blogspot.com/-7gS2Cuz3JSc/VQVgCqGhFLI/AAAAAAAABmU/Wxv8nRXOOHs/s1600/Volume%2BDifference.png
Toggle Commented Mar 15, 2015 on PIOMAS March 2015 at Arctic Sea Ice
Jim, The increased thickness in Baeufort seems mainly due to export from the Central Arctic. So that wouldn't affect the floe you cite. Virtually all of the volume increase is contained in the Central Arctic. So that wouldn't affect the floe you cite.
Toggle Commented Mar 15, 2015 on PIOMAS March 2015 at Arctic Sea Ice
Comparison of PIOMAS and the Arctic Basin fit from Lindsay & Schweiger 2015. http://4.bp.blogspot.com/-iGOMlvOFgdM/VP8wcrUAnqI/AAAAAAAABkE/W0Xvo7VHan8/s1600/Comparison.png Details at my blog. http://dosbat.blogspot.co.uk/2015/03/lindsay-schweiger-2015-thinning-of.html
Toggle Commented Mar 10, 2015 on Thinner and thinner at Arctic Sea Ice