Arctic Sea Ice

PIOMAS September 2017

ATTENTION: For the time being, the Arctic Sea Ice Forum is inaccessible due to a possible hack. I'll post an update once it's on-line again. Edit: It was a false positive, no hack, ASIF is back up again.

ADDENDUM 9.17.2017: If people have trouble logging onto the ASIF, read this thread.

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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:

It seems my prayers from May have been heard:

There's nothing else to do but hope that PIOMAS has it completely wrong, or else pray for lots of cold and cloudy weather in the Arctic this summer.

Well, the weather did its thing and produced one of the biggest turnarounds in the Arctic I have seen so far. I mean, in 2013 the ice managed to return from the brink of death, so to say, but at least the winter preceding it had been very cold. This year the melting season started with a record low volume after an incredibly mild winter.

One consequence of that mild winter, however, was lots of snowfall on the ice and adjacent land masses (see here). This snow likely managed to reflect some of the sunny weather that creates what I call melting momentum during May and June. So, with snow melting out late and not much melting momentum to speak of (yet again), it all came down to what kind of weather we'd be seeing during July and August. Cue low pressure.

Where PIOMAS showed the second lowest volume decrease since 2007 during July, volume decrease was by far the lowest during August, only 2029 km3 versus an average of 2633 km3. Second lowest drop happened in 2013 with 2221 km3. And so 2017 has been overtaken by 2011, the difference with 2012 has increased, and even 2016 - which had a massive August drop - managed to slip 6 km3 under this year's total on August 31st.

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

PIOMAS March 2016

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:

Again big changes. The year started out with the lowest increase for January in the 2007-2016 period (see last month's PIOMAS update), and now for February the second lowest increase has been reported. With a volume growth of 2047 km3 2016 came in well below all other years from the past decade, except for 2014, which clocked 1930 km3. Obviously, the increase in sea ice volume so far this year is the lowest on record:

What this means, is that - according to the PIOMAS model - the gap with pre-2010 years has widened even more. As of February 28th the ice pack contains well over 2000 km3 less ice than it did in 2008 and 2009, and almost 1500 km3 less than 2007. The gap with post-2010 years has all but vanished. 2016 is now in second place, just 124 km3 behind 2011. The gap with last year, the peak of the rebound after the 2012 record melting season, has now grown to 1900 km3.

Wipneus' version of the PIOMAS volume graph clearly shows 2016 right between 2011 and 2012:

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):

PIOMAS February 2016

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:

Big, big changes this month, and not for the good. Due to extremely high, or maybe I should say non-low temperatures in the Arctic the past month, this new year opens with the smallest monthly volume increase for January in the 2006-2016 record. 2007 saw an increase of 2848 km3, but 2016 goes one better with 2794 km3, in all other years volume went up by more than 3000 km3.

This means that, yet again, current volume has crept closer to the post-2010 years and widened the gap with pre-2010 years. Below the change in difference between January 1st and 31st is shown:

On January 31st 2016 the Arctic has just 104 km3 of sea ice volume than the same date in 2012, the year of the record melting season. The difference with 2013, the year that followed the big melting season, is still 803 km3, but it has gone down by 920 km3 in just the past month. The difference with last year (when two rebound years caused a marked increase in volume) has changed to a whopping 1692 km3. 2016 is still in 4th position, just like last month, but the gap with the top 3 has diminished radically. I could go on. Really big changes.

On Wipneus' version of the volume graph we can clearly see how differently the 2016 trend line moves from other trend lines around it:

PIOMAS January 2016

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:

As of December 31st total sea ice volume, as modeled by PIOMAS, is still lower than it was in pre-2010 years around this time. Because of rapid growth during December 2007, this year is no longer closest to the current value (739 km3 more). Now it's 2009 with 299 km3 more than now.

As for the post-2012 rebound years, 2015 is currently 128 km3 lower than 2013, but the difference with 2014 has gone down from 1308 to 1193 km3 less volume. The difference with 2012 has also gone down, but there is still a massive 1731 km3 more ice now than there was at the end of December 2012, almost the same number at the start of the year (1756 km3).

Here are the differences with all other years in the 2006-2015 period at the start and the end of the year in km3:

	Jan 1st	Dec 31st
2006	-893	-896
2007	191	-739
2008	279	-1241
2009	-140	-299
2010	870	995
2011	2174	640
2012	1756	1731
2013	2908	-128
2014	1019	-1193

Really big changes occurred in relation to 2011, but especially in relation to rebound years 2013 and 2014, where the difference decreased 3036 and 2212 km3 respectively during the course of a year.

As always I'm posting Wipneus' version of the volume graph which contains more years:

A difference in nonsense

There isn't all that much fake skeptic nonsense going round when it comes to Arctic sea ice. Climate risk deniers rather just ignore the geologic time scale event going on up North that could lead to an ice-free Arctic Ocean within one human lifetime. Still, every now and then an effort is made to trivialize Arctic sea ice loss. In this case it is done by averaging all daily sea ice extent numbers over the course of a year, and then claiming that Arctic sea ice is recovering.

The source of the claim is this graph based on MASIE data, which is the subject of this blog post. I'll get to that later, but here's the 'recovery' graph:

I'm not even going to link to the blog in question, because it's full of misleading and embarrassing statements by an older gentleman whose mind has obviously been set in concrete a while ago, and this particular nonsense has been taken apart by Tamino back in September. Of course this hasn't discouraged the blogger in question to stop misleading his readers, and his latest production of the useless annual average nonsense* has, again, been taken up by the free market fundamentalist ex-banker hobby organization known as the (no) Global Warming Policy Foundation.

All of this wasn't all that interesting to me until I compared the 'recovery' graph with an annual average graph based on JAXA sea ice extent data (found here):Here the trend line goes down instead of up, 2012 is lower than 2007, and 2015 has the 4th lowest annual average instead of 6th. That's quite a difference. What could be causing it?

Now, the MASIE FAQ page has this:

PIOMAS October 2015

I'm a bit late with this, as the latest data (up to September 30th) was released last week. To make up, here's Andy Lee Robinson's latest video showing the PIOMAS sea ice volume minimum long-term trend:

 

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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:

Sea ice volume stays relatively stable during September, with some years going up a bit, others still going down a bit. 2015 had a very small uptick of just 57 km3, similar to 2012's increase of 35 km3, so no changes there, this year still has 2000 km3 more ice than the 2012 record smasher. But with 2013 going up by 169 km3, the gap has become so small (289 km3) that this year is almost on a par with the first rebound year. And it's still 1087 km3 below last year's further rebound.

These differences are more visible on Wipneus' PIOMAS volume graph:

With 2015 ending as 5th on record, the trend hasn't gone back to the drastic decline of the 2007-2012 period, but neither has it confirmed any suspicions of recovery. It is simply continuing the downward linear trend, as can be seen on the PIOMAS sea ice volume anomaly graph:

2015 minimum overview, part 2

This is a continuation of Part 1, wherein I posted several graphs and maps depicting the 2015 minimum, and the weather conditions leading up to it (Tamino has a great blog post showing the long-term sea ice extent trends, all of them, not just the cherry-picked, meaningless one the GWPF selected to mislead).

Before jumping into the ice age and volume data that is (perhaps) most interesting, intriguing, but also incomplete, I want to refer to one more factor that - besides weather conditions and ocean heat flux - can play an important role in how a single melting season plays out: land snow cover.

Here are the monthly Northern Hemisphere snow cover anomaly graphs from the Rutger University Global Snow Lab during the melting season:

It's clear snow cover got pretty low during June and July. It's a bit of a chicken-or-the-egg kind of mutual influence thing, with an albedo feedback leading to warming over land, leading to increased snow melt, etc. which then starts to influence the Arctic and its sea ice as well. There's been ongoing speculation on this correlation between land snow cover and sea ice for years now, and my guess is that there's a there there, but as it isn't the only influence, it's hard to quantify it. Either way, it has to do with (global) warming, as attested by commenter Al Rodger's guest blog a few years ago: The untold drama of Northern snow cover.

And so we turn to multi-year ice. I'll repost this animation from a blog post I posted two weeks ago, showing how virtually all of the older, thicker multi-year ice on the Pacific side of the Arctic has melted out this melting season:

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:

PIOMAS September 2015

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:

 

After an August volume drop that was above average (only 2008 and 2012 had larger drops in the 2006-2015 period), 2015 has increased the difference with 2014 from 971 to 1245 km3, and further closed the gap with 2013, from 809 to 401 km3. Depending on what happens this month, 2015 could start the freezing season with a lower volume than the two rebound years.

We're seeing a return to trend, although there still is a considerable gap with years, like 2011 and 2012, that had 1625 and 1928 km3 less volume respectively at the end of August.

The differences are clearer on Wipneus' PIOMAS volume graph: