Arctic Sea Ice

PIOMAS November 2019

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:

During October there was a slowdown in ice growth, which is also reflected in the PIOMAS numbers. 2019 was the third year since 2007 to record a volume increase under 2000 km3. Given that 2016 increased even more slowly, it has overtaken 2019, which is now third lowest on record. But as can be seen on the graph above, the difference with 2012 (99 km3) and 2016 (31 km3) is negligible.

Here's how the differences with previous years have evolved from last month:

If you carefully observe the 2019 trend line on Wipneus' version of the PIOMAS graph, you'll see that it would have been lowest, had it not shot up during the last week of October (more on that below):

Winter analysis addendum

A couple of things were missing from the 2015/2016 winter analysis posted a few days ago, and so I've decided to present them in this separate blog post. Most of these images come from the website of NSIDC research scientist Andrew Slater.

Another way to express how warm or not-cold the Arctic has been this winter, is through so-called freezing degree days. The NSIDC explains it as follows in the All About Sea Ice segment of their website:

The relationship between thermodynamics and sea ice thickness can be thought of most simply in terms of freezing degree days (FDD), which is essentially a measure of how cold it has been for how long. The cumulative FDD is simply daily degrees below freezing summed over the total number of days the temperature was below freezing.

In other words, the sum of the number of days below 0 °C multiplied by the temperature for each day. Edit April 5th: I came up with a better explanation in the comments below. Here's a graph from the +80N 2m Tair page on Dr. Slater's website that shows this year's FDD compared to those of other years:

What can I say? This year's trend line is not only way outside of the percentile zones, it's falling off the chart. This comparison obviously corresponds well with the temperature charts and anomaly distribution maps I used in the 2015/2016 Winter analysis. But let me repeat that this isn't necessarily telling us anything about the coming melting season. As you can see, the blue line representing FDD preceding the 2011 melting season is rather high, but that melting season still managed to equal 2007, record holder at the time. Conversely, the yellow line is low, but the 2014 melting season turned out to be a second rebound year after the 2012 record breaking melting season.

Even though we don't know what will happen this coming melting season, we do know that those anomalously warm/non-cold temperatures have had a marked effect on the ice pack. As mentioned in the 2015/2016 Winter analysis the increase in sea ice volume so far this year is the lowest on record (PIOMAS will probably be updated in the coming week and I'm expecting March increase to be lower than the average of the past decade).

When it comes to sea ice extent and area, Cryosphere Today reported the lowest Arctic sea ice area maximum on record, as did the NSIDC for their Sea Ice Index (extent), and JAXA sea ice extent had the second lowest maximum on record (just 16K more than last year's record). As we can see on the JAXA SIE and CT SIA graphs this year's trend line is still the lowest of all in the 2007-2016 period:

Grasping at uncorrected straws

I rather not give too much attention to fake skeptics, or climate risk deniers as I like to call them, but lately they are somehow finding it in themselves to come up with stuff that they think disproves Arctic sea ice loss. I've already posted about MASIE annual average nonsense (about which the last word hasn't been said), but in the past couple of days an even more spectacular and desperate attempt at downplaying Arctic sea ice loss has sprung up. I'm posting it as a reference, because I'm sure this will become a (short-lived) meme.

It all started with a blog post on fake skeptic blogger Paul Homewood's blog Not a Lot of People Know That (NALOPKT) about how the Danish Meteorological Institute (DMI) got rid of an old sea ice extent graph "simply because it gives the 'wrong' results". I decided to partake in the discussion because I knew what it was about and the reason the DMI removed that graph was because it had been replaced by another graph months ago, accompanied by the announcement that it at one point would be removed. The graph had clearly been neglected as it diverged more and more from other SIE graphs.

It was a nice exercise for me to drive my points home, but I had no interest in posting about it here, as it was a typical mountain-molehill type of misinformation, sprinkled with some suggestive conspiracy ideation, on the fringe of the fake skeptic echo chamber.

However, for some reason Anthony Watts elevated it to WUWT status:

The word 'inconvenient' you see there is spelled incorrectly and should read 'incorrect'. Let me explain in detail what this is about, and how pathetically these climate risk deniers are grasping at straws. It's all about these two DMI sea ice extent graphs, on the left the old SIE graph with a 30% threshold, and on the right the new one with a 15%threshold (as used by most organisations around the world):

Many months ago the old graph was replaced by the newer one. There was still a link to the old graph below the new graph, accompanied by a text saying it could continued to be be viewed "for a while" (see the image in this Great White Con blog post). It's quite clear from visual inspection alone that something was increasingly wrong with the old graph, and the logical explanation was that no one at DMI was correcting it because it had been replaced by the newer graph.

In fact, this was my first argument in the discussion on the NALOPKT blog, but this didn't convince the fake skeptics who rather believed that the DMI removed the plot because, and I quote (lest you think my imagination came up with it):

2015 minimum overview, part 1

A week has passed by since the melting season ended and the minimum on all sea ice extent and area graphs has been reached. During this week I've been collecting images that show various aspects of this year's melting story, which will be accompanied by short explanations/interpretations.

Such an overview must inevitably start with an image showing the shape of the ice pack, and the University of Bremen has put up a great sea ice concentration map that also shows the ice pack outlines at the end of record melting seasons 2007 and 2012, as well as the 1981-2010 average:

2012 (cyan) clearly had less ice, but there are a couple of spots where this year had less ice than in 2007 (red). The September graph for ADS-NIPR/JAXA sea ice extent shows how close 2015 came to the lower years, slipping right below 2011 and ending in 3rd position:

The same can't be said of the Cryosphere Today sea ice area graph. 2015 ended relatively low there too, but at the top of the bundle of trend lines, in 6th position:

ASI 2015 update 7: to compact or not to compact

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2014 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything of particular interest.

The animation on the right consists of NSIDC
sea ice concentration maps, one for each ASI update.

Check out the Arctic Sea Ice Graphs website (ASIG)
for daily updated graphs, maps, live webcam images and
the Arctic Sea Ice Forum (ASIF) for detailed discussions.

September 1st 2015

Look at the sea ice concentration animation at the top right. Notice how the final frame suddenly is whiter than the preceding frame? That's a sign that we have entered the final phase of the melting season, when temperatures drop and melt ponds within the ice pack freeze over again. Sea ice concentration goes up, and the NSIDC SIC map becomes whiter.

But the Pacific side of the Arctic is still bluish. During the past two weeks the disintegration of that part of the ice pack has continued, spurred on by a late cyclone that further stressed the region (see special blog post on the matter) and increased the area that consists of a mix of ice floes and open water. The compaction potential of this region will probably decide where this melting season will end up on the various sea ice area and extent graphs.

And this end result still holds interest, because - somewhat surprisingly - the 2015 melting season could still achieve a top 3 minimum. Surprising, because the melting season started out with more volume, more multi-year ice, saw little and late preconditioning during May and June, and - despite a killer July - there has been relatively little transport and compaction this year.

With melting momentum mostly out of the picture now, it all comes down to compaction.

Sea ice area (SIA)

Here's the latest Cryosphere Today SIA chart, to which I've added preliminary data as calculated by Wipneus:

ASI 2015 update 1: early start in Beaufort

During the melting season I'm writing (bi-)weekly updates on the current situation with regards to Arctic sea ice (ASI). Central to these updates are the daily Cryosphere Today sea ice area (SIA) and IJIS sea ice extent (SIE) numbers, which I compare to data from the 2005-2014 period (NSIDC has a good explanation of sea ice extent and area in their FAQ). I also look at other things like regional sea ice area, compactness, temperature and weather forecasts, anything of particular interest.

The animation on the right consists of NSIDC
sea ice concentration maps, one for each ASI update.

Check out the Arctic Sea Ice Graphs website (ASIG)
for daily updated graphs, maps, live webcam images and
the Arctic Sea Ice Forum (ASIF) for detailed discussions.

May 19th 2015

Here it is, the first Arctic Sea Ice update for the 2015 melting season, and boy, are we off to a flying start. But more about that later. First a quick overview of what's been happening the last few years.

After the 2007 melting season smashed the 2005 record minimum, it was equalled by the 2011 melting season and subsequently smashed itself by the 2012 melting season. Although the 2013 melting season didn't bode well at all, given the trend and the massive amount of first-year ice, the Arctic sea ice had its traditional post-record rebound after a cold and cloudy melting season.

This (volume) rebound had all but vanished at the start of the 2014 melting season, but again the melting season started out cold and cloudy, after which the sea ice hardly moved during the rest of the melting season. And so there was a similar rebound to the one following the 2013 melting season. However, this time the volume rebound was larger and lingered on through winter.

One would think the ice pack would be strengthened and more resistant to weather conditions at the start of the 2015 melting season. But this also depends on how the volume is distributed across the pack, and as we saw in the 2014/2015 Winter analysis I posted 10 days ago, all of the volume has piled up in the Central Arctic and the Canadian Archipelago, the sea ice's last safe haven. This basically means that as far as the periphery of the Arctic sea ice pack is concerned, there is no big difference with the other post-2007 years. This melting season could turn out to be another rebound, but it might just as well go as low as 2007, 2011 or even 2012. The only thing we know for certain, is that the Arctic won't see below 1 million km2 of sea ice come September, the definition of 'ice-free'.

The outcome is obviously determined by weather conditions, but this month and June are particularly important for what I like to call melting momentum. This momentum is determined by the amount of melt ponds that form on the ice pack during these two months, as they soak up more solar energy that would otherwise be reflected. 2012 had a relatively sunny and warm start of the melting season, after which a stable decrease couldn't be thrown off by weather that was less conducive to melting. And that's how the record was broken, compounded by the Great Arctic Cyclone in August. Conversely, 2013 and 2014 had cold and cloudy starts to the melting season, and this couldn't be made up later on during bouts of sunny weather.

And so melt ponds will be the main theme of this first phase of the melting season. In fact, I'm going to obsess over them in the next two months and report on them outside of the ASI updates. The amount of melting momentum decides whether the melting season has a chance of breaking records.

Off we go.

Yamal to the rescue

A couple of weeks ago it was decided that Russian research station NP-40 (or SP-40 in Russian) would need to be evacuated, because the ice floe it was sitting on was breaking into pieces. There hasn't been any news since then, but apparently the evacuation started last weekend, as the German N-TV reports (hat-tip to Jorgenson).

Here's a picture of the evacuation:

Below I translate some of the juicier bits from the N-TV article:

New map on the block

Further down is a short update on the effects the SAC-2013 (Small Arctic Cyclone of 2013) has had so far, but first I want to draw some attention to a great new product that has recently come online, a sea ice concentration map with the highest resolution so far. When I started this blog the NSIDC used a 25 km grid, meaning that every pixel on their SIC map represented an area of 25 x 25 km, or 625 square kilometres, on the ground. IJIS had a 12.5 km grid and the University of Bremen even had and still has a 6.25 km grid.

Last year the GCOM-W1 (Shizuku) satellite was launched, with the AMSR2 microwave sensor aboard, and soon after that the Japanese space agency JAXA started to put out data. Alexander Beitsch from the University of Hamburg's KlimaCampus optimized the processing of this data, improving grid resolution to a stunning 3.125 km. This was part of his PhD in the framework of the IRO2 project that is being funded through the German Federal Ministry of Economics and Technology (BMWi). Sehr gut und danke schön!

There was just one problem with the sea ice concentration map that was produced, and that was that it was huge. 17 MB for just one image makes it difficult for us amateurs to play around with it. Luckily, the Arctic Sea Ice blog has some very smart bunnies on its member list, and it was Wipneus (well-known for his work on PIOMAS data) who managed to reduce the file size by ten times. For the time being he is putting those images on a separate Google Site. Thank you, Wipneus!

If this is real...

As usual, it's all about the if. Allow me to explain what this is about:

In the first Arctic Sea Ice update of the 2013 melting season that was posted a couple of days ago, I announced that a cyclone was forecasted to move over the Arctic Basin and stay there for a while. It's been there for a couple of days now as can be seen on this animation of Danish Meteorological Institute SLP images:

It's not particularly strong (especially not compared to GAC-2012), but it stays in the same spot for quite a while and so is bound to have some effect on the ice below. Now, according to the Naval Research Laboratory's ACNFS forecast model, this effect is quite pronounced. And to show you just how pronounced, here's their sea ice concentration animation from May 22nd, with a forecast up to June 6th:

Russia abandoning ice station

Guest Post by R. Gates

Russia has ordered an "urgent" evacuation of it's drifting ice station known as North Pole-40 that sits on top Arctic sea ice, because of disintegrating sea ice that is posing dangerous conditions to reseachers. This is one more indication that the thickness of the ice is now getting very thin at places it was not before, a metric not fully captured in the extent and area data.

Barents Observer reports:

Floating research station in need of evacuation

The scientific research station was placed on the ice floe in October 2012 and was planned to stay there until September. Now the floe has already started to break apart and the crew has to be evacuated as soon as possible.

Russia’s Minister of Nature Resources and Ecology Sergey Donskoy has ordered that a plan for evacuation should be ready within three days, the Ministry’s web site reads.

“A collapse of the station’s ice floe poses a threat to its continued work, the lives of the crew, the environment close to the Canadian Economic Zone and to equipment and supplies”, a note from the minister reads.