Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center:
The maximum for sea ice volume was reached during April. According to the PIOMAS model, it peaked on April 16th at 22,376 km3, which is the second lowest maximum on record, 1594 km3 above last year's stunning record low maximum, and 301 km3 below 2011's maximum. The total freeze during the 2017/2018 freezing season was the highest since 2013, but not all that much above the 2006-2017 average. This bar graph shows total freeze for the 2006-2018 period:
So, that's the maximum. After the maximum was reached, the trend line flattened, with sea ice volume going down by a meagre 91 km3 from the 16th to the end of the month, which can clearly be seen on Wipneus' version of the PIOMAS graph:
For a while it looked like the record for lowest maximum was going to be broken for the third year in a row, especially after an extreme warm event shook the Arctic. But this anomalous heat was followed by anomalous cold, which was just enough to nudge JAXA sea ice extent above last year's record low maximum. By 13 thousand km2, to be precise, which is around 0.1% of total sea ice this time of year.
I don't mind, as I correctly guessed both this maximum's date as well as the final number on Arctic Sea Ice Forum polls, probably for the first (and last) time in my life as an Arctic observer, as the maximum is incredibly difficult to pinpoint.
Here's the best visual representation of maximums throughout the years, produced by ASIF member Hautbois, as it shows when the maximum of a given year was reached, as well as how high it got:
Not a record low maximum, but the fourth maximum in a row that has ended up (well) below 14 million km2. That's for JAXA sea ice extent data (formerly known as IJIS, now provided by ADS-NIPR). The NSIDC has just reported that for their SIE product this year's maximum was also second lowest on record.
Looking at how much sea ice extent was created since the last minimum (total freeze), this past winter ended up fourth lowest since 2006. Of course, back in the day, minimums were higher than they are now, which meant there was less 'room' for re-freezing:
Here's the spectacular drop from anomalously warm to anomalously cold on the DMI 80N temperature graph, which normally isn't all that representative for the Arctic as a whole, but in this case it is:
Another month has passed and so here is the updated Arctic sea ice volume graph as calculated by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the Polar Science Center:
Just like last month, there haven't been any major changes, and that's good, because it means things haven't gotten worse (according to PIOMAS). But things haven't improved either. After a month of below average volume growth, the difference with number 2 in the rankings (2011), has decreased slightly from 1851 to 1731 km3. On the other hand the difference with 2012, the year when the lowest minimum on record was hit, has increased from 2099 to 2491 km3.
Here's how the differences with previous years have evolved from last month:
Here's Wipneus' version, showing the gap is still more than intact:
After a drop of almost 262 thousand km2 in just three days, it looks highly likely that the maximum for sea ice extent was reached two weeks ago, according to the data provided by JAXA, the Japan Aerospace Exploration Agency (via ADS-NiPR ; it used to be provided by IJIS).
It's a new lowest maximum record, and the third time in a row that extent stayed below the 14 million km2 mark. The previous lowest max on record was reached in 2015 (13.942 million km2), almost beaten last year (13.959 million km2), but this year SIE went lower still and peaked at 13.878 million km2.
This graph by commenter Deeenngee, posted on the Arctic Sea Ice Forum, visualizes maximums from the past and the trajectory to this year's max:
It looks highly likely that the max has been reached for NSIDC daily SIE as well (graph provided by Jim Hunt from the Great White Con blog), a third record low in a row if my eyes don't deceive me:
The drops are mostly driven by sea ice reductions in the Bering and Okhotsk Seas, but will soon be joined by drops on the Atlantic side of the Arctic as well, as the ice is pretty thin there, according to the Uni Bremen SMOS thin sea ice map.
Given the wind forecast, I also expect further sea ice retreat from the southern shores of Novaya Zemlya (similar to what happened in 2011 and 2012):
I started writing this blog post almost two weeks ago, initially wanting to call it Mad Max Beyond Thunderdome, as a logical follow-up to the event that I described as Mad Max last year. Max refers to the maximum Arctic sea ice cover that is usually reached around this time. It's Mad when the record gets smashed to bits. And it's Beyond Thunderdome when it gets smashed to bits after it got smashed to bits last year.
The thing is that a max record is only smashed to bits in one of the two daily updated datasets I follow with spreadsheets. Hence my retreat to the title of the first Mad Max sequel (hat-tip to commenter Taras Zelenchuk). Mind you, I'm not calling the max, as preliminary peaks may still be topped in the next week or two. However, it will take some extreme weather conditions for Cryosphere Today sea ice area to go up 400K and surpass the 2011 record:So, barring some extremely cold and windy weather, it looks highly likely that the CT SIA lowest maximum record has been broken, and if the preliminary peak of 12.843 million km2 remains standing, it will be the 2nd earliest max in the 2006-2016 period as well (together with 2007). Last year the max was reached at the astonishingly early date of February 16th, but it was still 130K higher than the 2011 record low max.
When it comes to JAXA sea ice extent (formerly known as IJIS SIE, but now provided by ADS-NIPR), 2015 was both the earliest and lowest on record by far, the first max to stay under 14 million km2. This year's preliminary peak, reached on February 29th, has so far stayed below 14 million km2 too, but is just 16K higher than last year's record, a statistical tie (and still a whopping 170K below the next lowest max from 2011). JAXA SIE has dropped 166K since the preliminary peak was reached, still in second place behind 2015:
Winter is supposed to be a time when things quiet down in the Arctic, animals hibernate in complete darkness, and all that can be seen from satellites is this great, icy mass getting bigger and bigger. That's how it goes most of the time, despite the spectacular summer sea ice losses of the past decades. But of course, there are exceptions, and this winter is one of those. In fact, it's an exceptional exception.
I want to highlight a couple of things to give you an idea of what's going on in the Arctic right now. As some of you may already know, this year's trend line is the lowest on record in practically every graph (see here). So far, it has played a major role in the breaking of Global sea ice area and extent minimum records, and it looks highly possible that last year's Arctic sea ice maximum record gets broken too. Mind you, that record was already spectacularly early and low, which is why I referred to it as Mad Max at the time.
It's a bit too early to be calling the max, which I vowed never to do again anyway, but here's the current situation on the Cryosphere Today sea ice area and JAXA sea ice extent graph (as provided by ADS-NIPR):
2015 peaked on this date in the CT SIA data set, but this year is currently 700K lower (last week's preliminary peak was almost 600K lower). The 2015 maximum occurred on February 15th in the JAXA SIE data set, but this year's preliminary peak is almost 274K lower. That's no small change, if things stay this way.
When area/extent is exceptionally low, it's usually a sign of something going on one side of the Arctic, while things are relatively quiet on the other side. This year, however, there's stuff going on on both sides of the Arctic. I'll start with the Pacific side of the Arctic, where regional extent is again very low in the Bering Sea, though high in the Sea of Okhotsk (these graphs are produced by Wipneus and can be found on the Regional Graphs page):
Here's a quick update on everything related to our good friend Max.
In the past couple of days organisations like the NSIDC, NASA and NOAA have announced the annual event of the Arctic sea ice pack reaching its largest size at the end of the freezing season. This has been picked up widely by the (online) media, probably more so because it's the lowest maximum on several records, and possibly the earliest, by a large margin.
NASA has put up a very nice, concise video explaining the whole thing:
Arctic sea ice extent appeared to have reached its annual maximum extent, marking the beginning of the sea ice melt season. This year’s maximum extent not only occurred early; it is also the lowest in the satellite record. However, a late season surge in ice growth is still possible.
I referred to this possibility 5 days ago in the Early record, late record blog post. Since then JAXA SIE has continued to drop, increasing the difference with the preliminary maximum. However, the last two days JAXA reported a total increase of 99 thousand km2, reducing the difference to 137 thousand km2. Here's a quick overview, using the Wipneus home brew AMSR2 regional SIE graphs (see this map for orientation), to see what happened where.
As expected, the Bering and Barents show an uptick in recent days (black and purple trend lines):
10 days ago I posted a blog post called Mad max. The title - referring to a very early maximum sea ice extent - ended with a question mark, because it was far from sure whether the preliminary max reached on February 15th would remain standing. This is because of the oscillatory nature of the final phase of the freezing season, where weather conditions can cause the ice pack to expand very rapidly in one or more of the fringe regions.
Here's how things currently look on the JAXA sea ice extent graph:Edit March 18th - A commenter sent me this updated graph today, with a correction (2010 had the latest max on record, not 2014):
Since posting that blog post, JAXA SIE dropped up to 318 thousand square kilometres below the preliminary maximum, but has since crept upwards again. The current difference is 186 thousand square kilometres, which still is quite significant. In fact, a new max becomes less and less probable as time wears on, with the Sun creeping higher in the sky, shining on larger parts of the ice pack every day.
At the same time, with extent relatively low, there's plenty of freezing potential on the fringes. And we're talking about the Arctic here. It has a reputation of crazy swings to uphold. Here's a map with the names of the regions that have a final say in where the maximum ends up, with the orange line showing the average ice pack edge for the 2000's:
And here are the graphs for each of these regions, produced by the prolific Wipneus, that show what has been happening regionally in the past weeks, with the purple line showing the JAXA SIE data for 2015.
Okay, I'm not calling the max - short for maximum extent of the sea ice pack that marks the end of the freezing season - as I've sworn not to do that anymore since 2012, when I called the max twice, only to see the trend line bounce up higher and later. But this year something really interesting is taking place.
It started almost a month ago, on February 15th to be exact. IARC-JAXA (IJIS) sea ice extent grew to 13,942,060 square kilometres, and the 2015 trend line was just below the middle of the pack. Nothing out of the ordinary. In the two days that followed extent went down by over 170 thousand km2. Still nothing out of the ordinary.
But the gains in the following 8 days, up to February 25th, didn't manage to make up for the deficit and the preliminary peak was still standing. Then a drop of over 240 thousand km2 followed, somewhat out of the ordinary, and that's where we are as of today.
I've made a graph showing what has happened since February 1st:
Last year, extent trended relatively low as well, but a surge in the middle of March made for a late max on March 19th. The current trend line is much lower, but there is enough refreezing potential on the fringes of the ice pack, as this sea ice concentration map from JAXA shows:
This is a guest blog I wrote for Climate Progress and Skeptical Science. You may use it as a new open thread to discuss the cracking event. I will try and do a more detailed winter analysis in April, if Allah and time permit.
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The sea ice cap on top of the Arctic Ocean is often imagined to be a monolithic, continuous sheet of ice floating on water. A closer look quickly shows it is rather a collection of larger and smaller pieces of sea ice. Of course, we have all seen the images of ice floes separated by open water during summer, but even during winter the ice pack gets fractured, leading to leads that quickly freeze over again. This explains how from the 1950's onwards submarines were able to emerge at the North Pole (the image on top is showing the USS Connecticut as it surfaces in the Arctic Circle on March
19th 2011; copyright: Kevin S. O'Brien, U.S. Navy). The subs couldn't break through the thick ice and had to look for a lead where the ice was thinner.
Strangely enough those who deny the reality and potential consequences of AGW still like to abuse this event and claim it somehow proves that nothing unusual is happening up North. It doesn't prove or disprove anything, as cracks and leads have always been a normal feature of the Arctic sea ice pack. But 'normal' is a word that has become less and less applicable to the Arctic in recent times. The 2012 melting season was the latest climax in a series of record years, that showed conclusively that the ice is thinner than it has been for a very long time.
We don't even have to await the coming melting season to see this re-confirmed. We can see it right now, at the end of the freezing season. Like I just said, cracks are a regular feature of the Arctic, but this video below, made by NOAA's Visualization Lab, shows a cracking event that is very rare, if not unique:
Ice, however thin, doesn't fracture by itself. It needs wind to pull the ice pack apart. This wind was provided by a big, intense and stubborn high pressure area that started about a month ago and kicked the Beaufort Gyre into action, which is an ocean circulation pattern that transports the ice in a clockwise fashion from the North American coast towards Siberia.
This short animation of ASCAT radar images shows the movement in 10 day intervals from January 1st onwards, compared to the previous three winters. The black dot represents the North Pole, the white mass below it is the northern part of the Greenland Ice Sheet, the brighter colours represent thicker multi-year ice that survived last year's melting season:
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