Arctic Sea Ice

Comparing

Last week, I opened a special thread over on the Arctic Sea Ice Forum to compare 2012 and 2019, because basically, that's what it comes down to at this point. In the thread, people post data, maps, graphs and satellite images to get an idea of how this year matches up with 2012. Towards the end of the month, I hope to use some of that material to provide a summary, before heading into the final phase of the melting season.

Today, one ASIF commenter called Comradez posted a YouTube video in which he compares 2012 and 2019 satellite images of one part of the Arctic (the intersection between the Beaufort Sea and Central Arctic Basin), which is exactly what I would hope to see when opening the thread. Here it is:

A couple of days ago, I saw this video on the broader implications of ice loss around the world. It's from one of my favourite alternative news channel called The Real News Network (highly recommended):

That's it for now. More to come towards the end of the month. We won't know whether the 2019 melting season will result in a new record low minimum, but we'll probably know whether it's still possible or not.

PIOMAS August 2018

PIOMAS data came in a bit later this month, and I'm a bit later still, but this gives us an opportunity to look at what may happen during the second half of the month.

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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:

Given the heat on the Siberian side of the Arctic and extensive melting in the Kara and Laptev Seas I had expected a larger drop. Nevertheless, a loss of 6229 km3 of sea ice volume is well above the 2007-2017 average of 6020 km3. This essentially means that 2018 has caught up some more with the years in front of it, and even slipped below 2016 (the difference is a mere 17 km3), which means it's in 5th position as of July 31. The difference with 2012 has been reduced with 610 km3, and is now 907 km3.

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

PIOMAS July 2018

What a coincidence. Just like last month, I will have to precede the PIOMAS update with a short news flash that a very strong cyclone is barreling through the Arctic. But this time too, the cyclone will be short-lived, and so it's not entirely clear whether, on the whole, it will be damaging or beneficial. It has gone further into the Arctic this time.

Either way, the cyclone' has bottomed out at 968 hPa according to Environment Canada, which is just 2 millibar more than last month's cyclone:

With their sub-970 hPa pressures these cyclones come close to the Great Arctic Cyclone of 2012 (963 hPa), but I think they lack in other parameters such as longevity to really deserve the GAC epithet. Nevertheless, to see two of these monsters in June and July in what hasn't otherwise been a very noteworthy melting season so far, is quite noteworthy. We might even see another one before the melting season is over, which could be a sign of some yet to be identified change going on in the Arctic, causing these extremely warm winters, followed by relatively cold and cloudy summers.

But that's all speculation. Let's look at the updated PIOMAS volume numbers.

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Talk about unprecedented

In the preceding post on Global sea ice minimum records getting broken for the third year in a row, I mentioned how the situation on the Pacific side of the Arctic was quite unprecedented, with the sea ice graph for the Bering Sea showing a sharp downturn (and even a small one for the Chukchi Sea). Well, there's an equally unprecedented event taking place on the Atlantic side of the Arctic as well. Yesterday, Prof. Dr. Lars Kaleschke from the University Hamburg tweeted out the following:

There is open water north of #Greenland where the thickest sea ice of the #Arctic used to be. It is not refreezing quickly because air temperatures are above zero confirmed by @dmidk's weather station #KapMorrisJesup. Wacky weather continues with scary strength and persistence. pic.twitter.com/YMnvCD8XvL

— Lars Kaleschke (@seaice_de) February 25, 2018

This probably has a lot to do with the splitting of the Polar Vortex due to a sudden stratospheric warming event a while back. I'm grateful for a bit of winter, finally, in my neck of the European woods, but not too happy about the consequences for the Arctic. The cause of all this heat and ice being pushed away from the northern coast of Greenland is an atmospheric set-up that during summer we'd be referring to as a Reverse Dipole (low pressure over the Canadian side of the Arctic, high pressure over the Siberian side). This animation of DMI SLP maps shows how the set-up got set up in the past 10 days, resulting in a pressure gradient as high as 75 hPa:

Such a pressure gradient means lots of winds. The animation in Kaleschke's tweet shows what happened to the ice between Fram Strait and the Lincoln Sea, but here are two images by ASIF commenters Uniquorn and A-Team showing the situation (from the 2017/2018 freezing season thread):

ASI 2015 update 6: one more high

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.

August 19th 2015

We are now entering the final weeks of the 2015 melting season. A relatively cold and cloudy start (not as cold and cloudy as the two previous rebound years) was compensated by a July that was ideal for melting. A continuous bombardment of heat and sunshine for weeks on end has caused some late melting momentum which is now keeping sea ice extent and area numbers dropping relatively evenly, despite a switch in weather conditions since the beginning of the month (see ASI 2015 update 5: late momentum).

As expected, the 2015 trend line on most graphs is hovering between top 3 years 2012, 2007 and 2011, and rebound years 2013 and 2014. It's difficult to tell how low things will end up. Melting momentum is one thing, but at this stage of the melting season weather conditions have the last word. It's compaction rather than melting that determines the final shape of the ice pack, and compaction depends on which way the winds are blowing, which in turn depend on the constellation of cyclones and anti-cyclones, or high pressure areas. See this blog post from an eternity ago, 2010, that explains how it works.

And now for the details...

Sea ice area (SIA)

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

ASI 2013 update 2: shaken and stirred

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 2005-2012 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.

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.

June 8th 2013

What the heck, I'm giving it another try (practice makes perfect):

The slow start I reported on in the previous update has continued, but as always in the Arctic there is more than meets the sensor. The slowness shows itself mostly in the area and extent numbers (changing as we speak), and the main culprit is that cyclone that refuses to go away.

I initially said this would be a relatively small cyclone, and even called it the Small Arctic Cyclone of 2013 in one of the two posts I devoted to it since the last ASI update, as a tongue-in-cheek reference to the Great Arctic Cyclone of 2012 (GAC-2012). But you know what? It ain't that small, and what's even more interesting: it just won't go away.

For over two weeks now it's been keeping things colder and cloudier over the central Arctic, but at the same time it's been shaking and stirring the ice, wherever it passes. Not to the point that it makes the ice disappear - this isn't August, most of the ice is still thick enough -, but it is showing how mobile the ice is, ripping holes in the ice pack that close up again once the storm has passed. It reminds me a bit of the 2010 melting season, when large regions with holes showed up in the middle of the ice pack.

So this cyclone is the big news of the melting season so far. Here's the rest.

Sea ice area (SIA)

Cryosphere Today sea ice area data had the trend line of 2013 way above all the others at the end of the month, but it seems that the limit has been reached. After a century break a couple of days ago a very big drop of almost 250K was reported today for June the 6th.

Here's the graph based on the latest data:

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:

ASI 2012 update 11: end or beginning?

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 IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 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 that can be of particular interest.

Check out the Arctic Sea Ice Graphs website for
daily updated graphs, maps and live webcam images.

September 22nd 2012

I left for a vacation after all the records had been broken and have returned just in time to see all the minimums get hit on the various graphs. In the past couple of years the National Snow and Ice Data Centre in Boulder, Colorado, has built up a well-deserved reputation of being the number one source of information when it comes to Arctic sea ice. When they called the minimum three days ago, it was picked up far and wide by news agencies around the world, an even better response than when all the records started to break one by one a little over a month ago.

I remember well the excitement I felt around this time in 2010 and 2011, checking all the graphs and satellite images every hour, trying to predict when the melting season would end. But none of that this year. Maybe it's because I still feel overworked, despite my vacation. Maybe it's because the records were broken so early in the season, preceded by several spectacular events. Maybe it's because this melting season was so freakish that it was practically impossible to pinpoint the minimum a few days in advance.

All those factors play a role, but what I think is going on, is that this stunning melting season has made me even more acutely aware of the gravity of what is taking place. This melting season has provided the final and definite confirmation that the ice is thin, PIOMAS has it largely right, and I have a very hard time finding indications that this is going to turn around real soon. To be able to watch and write about the Arctic sea ice, I used to block out the realisation of risks, so that I could make a joke here and there and be scientifically reticent in my own amateur way, keeping up appearances, acting objective.

But my bubble has burst. I'm already watching past the minimum. As the melting season ends, it feels as if things are only beginning. The age of consequences.

Sea ice extent (SIE)

Now that AMSR2 is operational, IJIS doesn't seem to revise the last data point, so I'm including it for this latest graph:

On September 16th the trend line shortly dipped below 3.5 million km2, reaching a minimum extent of 3.489.063 square kilometres. That's more than three quarters of a million below the 2007 record, and more than a million below 2011. I knew that there was a good chance the record would be broken this year, but never imagined it would be by such a large margin. Especially not with circumstances that in many ways were the opposite of those in 2007.

The current difference between 2012 and other years is as follows:

Arctic Basin SIA dips below 2 million km2

The record for the most important region on the Cryosphere Today regional sea ice graphs page was broken 2 weeks ago. But it didn't stop there. In fact, it hasn't stopped yet. It seems the plateau since 2007 was short-lived:

ASI 2012 update 10: (wh)at a loss

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 IJIS sea ice extent (SIE) and Cryosphere Today sea ice area (SIA) numbers, which I compare to data from the 2005-2011 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 that can be of particular interest.

Check out the Arctic Sea Ice Graphs website for
daily updated graphs, maps and live webcam images.

August 25th 2012

I apologize for having provided so little analysis lately, but things are moving so fast that analysis can't keep up. Now I know what an IPCC regional model for the Arctic must feel like. ;-)

Basically, I'm at a loss for words, and not just because my jaw has dropped and won't go back up as long as I'm looking at the graphs. I'm also at a loss - and I have already said it a couple of times this year - because I just don't know what to expect any longer. I had a very steep learning curve in the past two years. We all did. But it feels as if everything I've learned has become obsolete. As if you've learned to play the guitar a bit in two years' time, and then all of a sudden have to play a xylophone. Will trend lines go even lower, or will the remaining ice pack with its edges so close to the North Pole start to freeze up?

Basically I have nothing to offer right now except short posts when yet another of those record dominoes has fallen. Hopefully I can come up with some useful post-melting season analysis when I return from a two-week holiday.

I'm at a loss at this loss. The 2007 record that stunned everyone, gets shattered without 2007 weather conditions. The ice is thin. PIOMAS was/is right.

Sea ice extent (SIE)

WindSat or no WindSat, the 2012 trendline on the IJIS SIE graph has dropped like a rock:

I had to adjust the Y-axis on this graph already once (compared to the one in the last ASI update), and it looks like I'll have to adjust it again. I already announced the new IJIS SIE record minimum yesterday, although it was based on the preliminary number. But after the revision the record is still standing and IJIS still hasn't stopped producing century breaks.

The current difference between 2012 and other years (without the unrealistic last data point that gets revised upwards) is as follows: