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Nares running backward, CAA melting inside but not outside very much, Beaufort ice near the coast intact but the CAB on the Beaufort side taking a beating. Still having ice in the Hudson and the Baffin ice is slowly melting away. It is extremely odd. However, unless something changes radically, it's still unlikely to make a new record. Although the Atlantic side is now beginning to show a rather feathered shape as though it is taking a significant beating without giving up too much extent.
Don't be too quick to write it off Wayne. The NSIDC chartic is now showing a step away from 2012 at the point that 2012 was very rapidly dropping. The thin, weak, ice in the Beaufort and the ESS may have vanished quickly, along with the peripheral ice which should never have still been there. But we don't have a GAC and things are trending slightly back to the norm. Time will tell as to just how much the thin ice and the mobility of the ice will push 2018 over the edge. More interesting watching to go. The ice is so thin and weak that surprises are bound to happen. It is, now, virtually impossible to say X happened then and Y will result today. Every model is now a moving target and even direct comparison won't yield the same results because we simply don't have enough quality in the data that we use to compare. One thing is for sure. 20 years after the ice has gone for the first time, there will be a perfect scientific article which tells us why it happened....
Thanks Neven that is a huge amount of work to try and analyse an arctic which refuses to conform to any norm. I'm guessing that the Arctic is transitioning state so fast now, as it moves to a new blue ocean state, that prior methods of analysis are going to give different end results. Even if this year doesn't make top 3, pretty soon almost any melt season, conducive or not, is going to produce top 3 results. Essentially the poles of the world have a cooling budge and a warming world has almost spent the Arctic one.
NSIDC shows the Extent pulling back away from 2012 now and running parallel. From Wednesday 2012 recorded a straight 10 days of 100k breaks. Given the huge losses we have just seen, with peripheral seas and the Beaufort collapsing, it's going to be interesting to see if 2018 can emulate it. Not sure about that but it will bear watching. The next two weeks will give us a clearer idea of just how bad the CAB ice is and how likely it is to melt. DMI continues to show 2018 80N temps as lower than the melt years and we know it has been snowing up there. This is going to be another interesting one to watch. I could understand it if 80N were at 1C, the ice was melting under clear skies and that the temp level was due to the ice. But we have seen constant cloudiness over the CAB all summer. We shall watch and learn.
Toggle Commented Jul 30, 2018 on PIOMAS July 2018 at Arctic Sea Ice
Of course if you believe that the Arctic seasons are moving in cycles, personally I've come to the conclusion of two, roughly, 5 year cycles moving in a 10-11 year cadence, which corresponds to the peaks and troughs of the solar sunspot cycle; then this all makes perfect sense. If you think of it as two hotter years, two cooler years and one in-between year, then things match better. In the cooler years it takes excessive weather and truly catastrophic ice conditions to create records. In the hotter years it takes moderately good weather to produce high melt and it takes exceptional weather to stop it melting. What we saw in 2007 and 2012 was the two different scenario's. 2007 was disposed to melt and had exceptional melting weather. But it also had a fairly cohesive pack and a hell of a lot more ice to melt. 2012, on the other hand did not have really conducive melting weather but it just kept on melting. Then the GAC took over and it is the record we see today. It is why I predicted that 2006 would not make a record. It was why I predicted 2017 would, but weather took over and damped it down. It is also why I predicted that 2018 would be a poor melting season and talk of "recovery" would surface. Ditto 2019. The thing is that the sheer weakness of the ice has taken over to some extent. We have more heat transfer in winter from the sea because the ice is thinner. Then again we have more heat transfer to the sea in summer due to the same thinness of ice. Here, again, weather comes into play in a much bigger way. If the ice is thin and fragile and the sun can heat the sea below, right through it, causing more bottom melt, then the weather is going to play a much larger part than it might have when it blocks the sun. Essentially because it is not just blocking the melting of the top ice, it is blocking the heating of the ocean through the much thinner ice. Equally very cold temps in winter, especially late winter, with thin ice, will cause much faster than expected ice creation, for that time of year, as the thinner ice will not insulate the ocean so well. Today the solar sunspots have been blank for nearly a month. It will be interesting to see how long that goes on. 2008/2009 had the lowest solar minimum recorded in the last 100 years. I'm sure nobody has forgotten, just yet, how cold the winters of 2008/9 and 2009/10 were in the northern hemisphere? It wasn't all jet stream. So, after all that rambling. You probably don't need me to tell you what I think will happen in the "middling" year of 2020 and the "warmer" years of 2021/22, sitting right on top of the sunspots of solar cycle 25.... It is a _very_ long prediction, in terms of what we normally talk about here and the forum. However, as I have been watching for over 20 years now, I'm not that impatient.
Toggle Commented Jul 21, 2018 on PIOMAS July 2018 at Arctic Sea Ice
DCS, whilst the logic of losing a greater amount, of less ice, means that less volume is lost overall; there are a few gotcha's in that calculation when it comes to the reality of sea ice loss. First and foremost is that the amount of ice lost tends to be correlated to the amount of energy entering into the system. Given weather and other mechanisms throw a spanner in the works, it is still a case that measured w/m^2 input gives us x% of ice loss. If we have less ice to lose, then the ice is not doing its job of offsetting the input of energy. In that case, in a 2007/12 scenario, the ocean and land of the Arctic is going to take up the offset with heat absorption. Whilst more sea is roughly equivalent to more heat transferred to the atmosphere at the onset of winter, the rapid onset of Arctic winter can cap the heat transfer and retain a portion of that heat. Regardless, instead of reflecting and radiating out to space or being used to transition ice to water, the heat will be absorbed and some will remain in the system. You mentioned that in terms of albedo but not in the sheer amount of fusion energy required to change ice to water 333kj per kg, without changing the temp by 1k. The less ice we melt to water, the less fusion energy we take up, over and above all the other energy to move it from -5 or less. Essentially we have a smaller aircon so we get hotter. How this balances with having a smaller blanket (initially), in winter is an interesting point, but the other point is that this heat, initially, transfers to the local atmosphere. Inhibiting further ice generation until it can be moved away by the weather systems. The other point you didn't mention is this. Right now the thermal inertia of the current volume of ice is greater than the thermal inertia of any single melting season. Thus it is, essentially, impossible to lose the entire pack in one melting season. However, as the average thickness of the ice reduces towards 1m and the area of that ice declines, we reach the state where the thermal inertia of the ice becomes less than a single exceptional melting season. Which puts the Arctic into a shooting gallery for any exceptional melting season. So whilst the math and the stats are valid, in terms of reduction; so is the fact that the entire system can flip to another state right in front of our eyes.
Toggle Commented Dec 3, 2017 on PIOMAS November 2017 at Arctic Sea Ice
Due to picking up a new job in the "project from hell" arena, I completely missed the entire end of the melting season. As Neven says, Nothing can be taken for granted with the Arctic. For me the most concerning thing is we saw exceptionally low summer temperatures, yet we still finished 4th. Which means that the damage was already done in the preceding year and in the preceding winter. I wonder if we'll eventually see this as a small bounce driven by the end of an exceptionally strong Nino which overwhelmed the early signature. I guess the post mortem of the 2017 melt season will take a few years and throw up a few interesting things. I'm now in watching mode till the end of the 2018 melt season as I want to see how it all plays out.
Toggle Commented Nov 5, 2017 on PIOMAS October 2017 at Arctic Sea Ice
Bill I did notice it and I hope you'll take my apologies for not commenting on it when you know I am extremely interested. I made the mistake, on the forum, of stating my claims that 2016 would be the penultimate year of a 5 year cycle when the vast majority of people on the thread believed it would be a record breaker. I made the bigger mistake of making these predictions between early May and early June 2016. Given that this year is not over and that my prediction of 2016 may, yet, fail, I hope you can forgive me for not making any big thing about cycles and what they do to melting expectations. I have made no real predictions about 2017 apart from voting for an end extent somewhere either above or below the 2012 low. The reason I voted for that is precisely because of the 5 year cyclical variation which we are watching unfold. Simply put the weather, at the peak of a 3 year melting cycle (two growth, three melt in the cycle of 5 years), would have to be exceptional to "stop" significant melting from happening. What we are seeing today is that the entire pack, right up the pole, is vulnerable to moderate storms and that ice which is neither thick, nor integrated, can vanish in a day, rather than the week or more it took 2012 with the GAC. As such, that vulnerability driven by the 5 year cycle peak, is what is driving my expectation of an end result closer to 2012 (above or below), than to 2007/2016. My comments last year were also driven by vivid memories of 2006 and how it unfolded. It was uncanny just how close the two effects were and it fits very well with the 5 year cycle vison. Every time I talked about this I was clear to state that 2016 was in the context of post 2007 and 2012 years. In other words the same cycle event, with similar weather, was going to deliver much lower results in terms of remaining ice. However these results, still, comparatively to 2007 and 2012, were going to produce end year minimum results which echoed the same year in the previous cycle. Even though they may not be records in their own right. I was correct, 2016 was more comparable to 2006 and 2011, with the exception that 2016, if cycles were repeating exactly, would have finished very close to 2012 rather than being almost the same as 2007/2011. The cycles do not repeat exactly, how could they, solar insolation cycles on a ~10 year rotation and the impact is different between the beginning and end. Also solar cycle 24 has been roughly half as intense as cycle 23. My point in that being outright numbers do not make the cycle nonsense. 2003/4 ice grew in the Arctic and declined in 2005/6/7. 2008/9 ice grew and declined again in 2010/11/12. 2013/14 ice grew in the arctic and declined again in 2015/16 and, it would be safe to assume, 2017. That, to me, is a cycle regardless of the outright numbers or whether a new record was achieved or not. If we accept the cycle is there, then a broad expectation can be set that 2018 will fall somewhere outside the top4/5 for melt. Regardless of whether 2017 beats 2012 for melt or not. For me, that is much more reliable than whether the end number is lower than the previous year or not and whether the end of a cycle (as 2017 is), beats the previous records or not. This is why I also say that we're much more likely to see a Black Swan event in 2022 than in 2017. Each cycle, essentially, drops the volume towards the end before ticking up a bit for 2 years. That can't go on. If we saw the same volume loss in 2020/21 as we have seen in 2015/16, there wouldn't be much left to melt in 2022 regardless of cyclical drops. So I'm not really talking much about cycles until the end of the 2018 melt season. Which is where my, end spring, 2016 predictions, run out.
Toggle Commented Aug 7, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Let me quantify. "We believe" was Hans and me as I was replying to his question.
Toggle Commented Aug 1, 2017 on PIOMAS July 2017 at Arctic Sea Ice
How about a slightly different question. If, as we believe, the cycle has years predisposed to melt as well as years predisposed to ice growth, then it would take exceptional weather to stop the melt this year. That is somewhat different than believing that it will take exceptional weather to create a surprising melt this year.
Toggle Commented Jul 31, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Thanks Jim, I should have said tends to be saltier. That would have been better and more accurate.
Toggle Commented Jul 24, 2017 on PIOMAS July 2017 at Arctic Sea Ice
AJbT, because we know the SST's in the areas where it is melting and we know that the currents draw that warmer water under the CAB. Prior Buoy data over the affected areas has given us a wealth of stats which show a range of bottom melt during the season. We also know the thickness of the ice and we know that FYI suffers from solar penetration and insolation of the solar energy in the water below. Also causing bottom melt. FYI is predominantly salty ice which has not built up a store of snow and frozen water from rain which did not escape. Salty ice melts at -1.8C. So we know bottom melt is going on, we know roughly how much will melt, in a normal season and we know how thick the ice is. That is leading to some concerns as to the retention of the ice this melting season.
Toggle Commented Jul 24, 2017 on PIOMAS July 2017 at Arctic Sea Ice
I noticed the same thing Hans. Where it is melting on the Atlantic side, it's coming around the coast. Where it is not melting in the CAB, it's coming over Greenland and rotating over the CAB. What is more interesting is the state of the ice on the Atlantic side, now showing on the Bremen concentration maps as areas of open water N of 85N. Also the bottom melt continues but is relatively invisible at this time. It's going to make August rather interesting.
Toggle Commented Jul 23, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Not quite AJbT. I used to put every day under the microscope, I used to try and understand why each day and week were doing what they were doing. None of it made any sense because every year seemed different. It was only when I took a step back and looked much further out and did comparisons way beyond day, week, month or year that some things seemed to make sense. But, yes, I'm still trying to learn. I didn't use to have much patience for RealClimate's assertion that you could only see what was happening on a multi decadal scale. Especially when things were moving so fast and accelerating so fast. I have moved much more towards their way of thinking over the last few years.
Toggle Commented Jul 20, 2017 on PIOMAS July 2017 at Arctic Sea Ice
I was recently looking back through the Chartic extent. Roughly: 2006 reached the 2003 low 2011 reached the 2007 low But 2016 only really equalled 2011. It didn't reach 2012. So, in a way, I would not be surprised if we only equalled 2012 or went under it slightly. Of course if we went significantly under it, I would not be surprised either. However, for me, I'm still looking forward to 2018/19 to see whether we continue with the losses of 2016/17 or whether we go back to a cycle of very limited re-growth for 2 years. What is looking most interesting, to me, is the swathe of ice in the 80n to 85n from Svalbard to the Chuchki. That looks vulnerable to a storm or two which could cause a very significant change in the ice. Or not.. That is the whole thing about watching the Arctic. For me I have come to the conclusion, in my quest to understand why the ice does what it does, that if we have 5 year cycles, then each year within that cycle is a different melt season. 2017 is peak melt so should act like peak melt. 2018 will be peak growth and should act like peak growth. It has been and will continue to be very interesting to watch.
Toggle Commented Jul 20, 2017 on PIOMAS July 2017 at Arctic Sea Ice
We, it seems to me Hans, are talking about serious advection of heat: are we not? I'd say we have already had serious advection of heat in the form of rain, all over the season. The main reason it has not really registered heavily so far, in terms of overall ice melt, I'd guess, is the very heavy snow cover. But that heat is there and it's not going away. More heat just increases the impact on an already weakened system. This seems to me to be one of the drivers that has driven the state of the CAB where it no longer resembles a pack.
Toggle Commented Jul 19, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Looking at the way the Atlantic side is disintegrating, on the Arctic Mosaic overheads, I'm quite interested to see how close the daily Extent on NSIDC gets to 3M There is now significant damage on the Pacific side, significant damage on the Atlantic side and the periphery is finally succumbing to the relentless heat and rain. Volume is also showing that it's starting to dip more sharply again, hardly surprising given the amount of area and extent that has been vanishing in the last two weeks. NSIDC running 5 day average has 2017 just above 2012 but closing as the higher rates of loss in 2017 compare to the lower rates of loss in 2012 at this time. Regardless of what happens now, it looks like 2017 will drop well below 2016 and I'm looking forward towards the next freezing season and how it evolves. Personally I see the next two freezing seasons and their attendant melting seasons following as the final story in the potential for a 5 year cycle.
Toggle Commented Jul 18, 2017 on PIOMAS July 2017 at Arctic Sea Ice
P-maker. I know you weren't discussing a cycle. Only a few of us do that.. :-) Apart from the fact that pretty much all the peripheral ice melts out nowadays and the peripheral ice is mainly very thin, I would assume that less surface contact with heat transfer would generate less melt. It doesn't matter quite so much if there are 100,000 sq miles of warmer water or 1M sq miles of warmer water, if only 80,000 sq miles of water is in contact with the ice whereas before there was a full 100,000. Yes there is a larger "warm sink" but heat transfer through water is not very fast and also the melting ice creates a barrier between the ice and the warm water surrounding it. At least for a while.
Toggle Commented Jul 15, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Hence, the June cliff may be the cause of the late summer decline in total loss (simply less ice available). Oddly I thought that was what I'd said.
Toggle Commented Jul 14, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Rob, would that be due to the fact that there was more peripheral, weak, thin, ice out there later in the season in the 80's than now? We have seen all the peripheral ice melt out in the last decade, only leaving CAB ice behind. This was not true in the 80's. As the ice reaches total failure point, volume loss, in the latter part of the season, must start to fall in the charts because there is simply less surface area, everywhere, to absorb heat, because there is less area and extent. The more compact the ice the less area too. Then, of course, we have to wonder about rotten ice. It gives every signature of MYI, but has the strength and heat absorption capability of FYI or less. We know the satellites can't detect rotten ice so, I wonder, how do the models compensate. If the ice is melting from within, but not giving a signal of melting, then, would we not, see something similar to this slowdown? I did find an abstract about the heat sequestration and transport of melting snow cover on ice, I requested the full article and received a reply of "when the authors deliver it". I think, in the case of this year, it could be important too. Right now we are almost at solar minimum, Nino is neutral, there does not seem to be any single,"normal" driving force for what we are seeing today. Yet, we're bumping along the bottom of the lowest charts for Extent and Area and off the bottom for Volume. This would fit the hypotheses of a cycle, where the Arctic responds in a certain way throughout the cycle. Influenced by strong weather, certainly, but without strong influence it continues on the path. The CAB is in a very poor state today, peripheral areas to the CAB are likely to melt out, the NSR and the NW passage look likely to be open in the next 2-3 weeks and we still have August and the storms it might bring to come. The last 3 days has seen Extent drop by an average of 132k per day which will drop 2017 much closer to 2012. 2012 only averaged sub 100k over those same days. However the overheads show the peripheral ice changing colour and likely to disappear faster, not slower. Nothing can be forecast, right now, from observations because they are not that consistent. That being said, we can make some assumptions. My assumption will be that this melt will continue to exceed expectations in the periphery and the CAB will continue to show a weak and broken state. That then leaves us in the shooting gallery of August storms as to whether there is a record or not. I do, however, expect it to drop significantly below 2016.
Toggle Commented Jul 14, 2017 on PIOMAS July 2017 at Arctic Sea Ice
Thanks for the time and insight Bill. I won't even discuss this in the forum any more, the discussion is too toxic. I was doing no more than setting out my stall for why I believed that 2016 was going to stall, why it was not going to make a record and why I believed it was going to set the scene for a 2017 which could be a record breaker. In contrast to the "false alarms" and predicting abrupt sea ice loss, I believe Hans and I have been doing the opposite. Where we are predicting another 2 year pause on the journey to destruction starting this freezing season and rolling back again in 2020. Then leading up to another sharp drop again in 2022. I have been very careful not to promote huge new records for 2017, but have talked more about unexpected levels of melt for the year consistent with ending the 5 year cycle. If we look at 2017, with high snow cover, low volume and indifferent weather, the levels of reduction in all three metrics are, in truth, unexpected. 2017 should not be at, or around, the bottom of the extent and volume tables given the atmospherics. One other point. I was looking back to 2002 on the AMSRE archive on the Bremen site when I realised that, looking at the images, we are in the 3rd round of a 5 year cycle. Have a look at 2002, the re-growth in 2003/4 and the path to 2007 with 2005/6 leading the way. It may not be so obvious from the numbers but it is quite obvious from the shape and pattern of the ice. In the end, there is nothing left to do but wait. We won't know, for sure, until Autumn 2018 whether this is going on, still, or not.
Toggle Commented Jul 7, 2017 on Melting momentum: May 2017 at Arctic Sea Ice
I'd say more like Heartbroken that Neven doesn't have the time to fully embrace the defining events of our lives and communicate it to us all in his excellent style. It is soul destroying to see what is happening but be unable to keep this community engaged and talking and visible to the world; so that everyone can understand what is going on. My view? Regardless of what is happening and how important this is, family comes first. After family there is time to worry about everyone else. This is slow enough moving with such huge inertia behind it, that it will still be here in a few years when family pressures have eased and there is more time in life.
Toggle Commented Jul 7, 2017 on PIOMAS July 2017 at Arctic Sea Ice
I guess time will tell Rob. 2017 is still at the lowest on volume, almost at the lowest on extent and not there yet on area. As you say snow has had a big impact but, also, snow has insulated the ice over the winter from growth and, in many areas, is 0.5m thinner than it should be. I know very well that area is the figure to follow, but unless I build my own charting model from the data, chartic is the easiest tool for me to use right now, given that CT area is now gone. So I'm watching extent. The Beaufort is almost open to the Pacific, the Laptev, ESS and Chuchki are all continuing to draw back. The Laptev bite is well in progress and the big unknown is what will happen with the Atlantic side. We have 3 weeks of July left and all of August. Whilst extent may be stalling, there is a lot of peripheral ice out there which is vulnerable and will likely melt out. Whatever happens, it will be extremely interesting. More so because of the lack of melting input, compared to the state of the ice.
Toggle Commented Jul 7, 2017 on Melting momentum: May 2017 at Arctic Sea Ice
Thanks Bill, I knew about the rolling daily average but wasn't quite so aware that the values in the spreadsheet were monthly averages rather than lows. That makes a lot of sense. The problem with the 5 year cycle is that we won't know, even at a low level of certainty, until 2020. Because 2018 and 2019 need to show some re-growth from a low in 2017 and then the cycle of dropping melt needs to begin again. For me the real evidence won't come up until 2021/22. If we see second iteration of 2006/7 this year followed by a re-growth and then a third one in 2021/22, then I'd say that it's fairly certain that a cycle is going on there. This month is a busy month in the extent records. Years drop into and out of the record lows this month. 2010 and 2006 drop out. 2011 drops in and out again, 2012 gets set to smash all records in August/Sept. Much more waiting to go before we have any idea how it's going to end up, but even then one GAC and anything could change. Some of this ice is very thin and other ice is thinning without vanishing. I recall the ice in the Chuchki/ESS which just looked like smoke on the water. It was counted fully as extent and area but when the GAC came it just vanished. So I'm making no predictions right now, but the fact is that 2017 is right at the bottom of the charts right now and the only reason it is there is the very sorry state of the ice from the 2016 melt and the very low winter ice growth into 2017. Which leaves the ice very vulnerable.
Toggle Commented Jul 6, 2017 on Melting momentum: May 2017 at Arctic Sea Ice
Thus continuing the 5 year cycle as far as I'm concerned. Of course for that to truly continue we'll need to see ice re-growth and slow summer melt in 2018/19. There is also the opportunity for some more than average melt in July and August, therefore driving 2017 even lower. I believe, if I remember correctly, that 2012 was not an exceptional season until the GAC. I believe my focus on Arctic melt has changed. I still watch it daily to see what is going on but my anticipation levels have changed to annual rather than weekly or even monthly. I no longer obsess over the next few days or weeks. I am looking months forwards and backwards. Whilst not as instantly gratifying, the overall experience is more positive.
Toggle Commented Jul 5, 2017 on Melting momentum: May 2017 at Arctic Sea Ice