Back in July, I wrote two posts on the Arctic sea ice annual minimum, one about the sea ice extent and one about sea ice volume. In the meanwhile, there was a new minimum in September 2022 and I wondered what the evolution was of those minima. This post is an update on the volume as well as the extent graphs.
Let’s start with the volume data. This is a plot of the annual sea ice minimum extent from 1979 until 2022:
Just a short post. In previous post, I lamented whether I was the only one who wondered about the trend change of Arctic sea ice and trying to visualize it. Doing an ultimate search using several search engines, I finally found a graph that visualized that same trend change, although in a bit different way. Surprisingly enough, I found it on the NSIDC website (scroll down until “September 2019 compared to previous years”):
Reading previous post on the Arctic sea ice extent, you could ask yourself: what about the Arctic sea ice volume? Well, that is the exact same question that I asked myself when I was busy creating the minimum Arctic sea ice extent graph. It was a long time ago when I looked at the Arctic sea ice volume data. That was in 2016, at the time when predictions of an ice free Arctic, that until then were based on sea ice volume, suddenly switched to sea ice extent and I was a bit puzzled by that back then.
In 2012, Peter Wadhams predicted an ice-free Arctic by 2015 based on the “exponential” decreasing Arctic sea ice volume trend. He illustrated it with this graph:
That graph was also the inspiration for the updated minimum Arctic sea ice extent graph in previous post. Let’s now do the same in this post and upgrade the minimum sea ice volume data and see what happened after 2012.
There was some controversy about Arctic sea ice in May of this year. Back then, I saw some (contradictory) messages in a quick succession. First, there was a tweet claiming that Arctic sea ice extent was the same as in 1989, followed by a fact-check claiming that this was just cherry-picking and that it in fact going steadily downhill, finally a reply that also the fact-check was cherry-picking and overall sea ice extent was just fine.
So, what is it? Is Arctic sea ice going to hell in a handbasket or is it doing just fine, already recovered to 1989 levels?
It is several years ago since I looked at Arctic sea ice extent data and at that time there was what seems to be a modest beginning of a pause, so I was curious how it evolved since then. Did that pause continue or is it straight down again?
Let’s first look at the arguments from both sides. It all started with a tweet containing this comparison:
Two posts ago, on the subject of another claim of an ice-free Arctic published in the Guardian, the discussion arose whether the journalist realized that he quoted someone with a poor track record in that matter. Commenter Chrism56 alerted me that the journalist (Robin McKie) already had written articles in the past on this subject, so he should have known that there were issues with the credibility of this claim.
The link that was provided went to an article from 2008 in which McKie reported about the claim of an ice-free Arctic that back then was expected five years further in the future.
The claim was made by Serreze, Maslowski and Wadhams. Apparently he should know about the botched prediction in the meanwhile.
I became curious whether there were more articles written by McKie on this topic and also how he wrote about it in say 2013, when it became clear that the 2008 claim didn’t hold. I found three articles in the Guardian about an ice-free Arctic and the article in 2016 was the fourth. When reading them in the sequence as these were written, it developed in something rather funny.
Let’s start with the link found by Chrism56. It was an article from August 2008 with the title “Meltdown in the Arctic is speeding up”. This speeding up was explained as (my emphasis):
It was to be expected: Wadhams has renewed his claims of an ice-free Arctic. The Guardian published on August 21 an article with the catchy title ‘Next year or the year after, the Arctic will be free of ice’.
In a previous post, I already compiled quite a list of predictions of an ice free Arctic. At that time (June) it was rather unlikely that this year we would see an ice-free Arctic. But no problem, 2017 was already on the radar back then. When looking at the statements in the Guardian article, now it will be next year (summer 2017) or the year after that (summer 2018).
Another year to add to the list.
There was more in the article that caught my attention. Like the first paragraph of an interview with Wadhams:
Although I respect the expertise of Wadhams, a puzzling thing was the insistence that the downward trend since the measurements is necessarily “abnormal” and caused by our emissions. I have no problem accepting that he saw drastic changes in the Arctic concerning the height / volume of the polar cap during his long career and that this was the reason why he thought that the Arctic would be ice free soon.
For the record, I have no problem whatsoever believing that the Arctic underwent changes in the last 40-50 years. But logically, we only start measuring the ice of the poles since the end of the 1970s. If we only started to measure AFTER the supposed cause started, then logically what is the “normal” extent and volume of the Arctic?
Central in previous post were the predictions of an ice free Arctic by Peter Wadhams. While reading his predictions several things stood out. One of these things was that his early predictions seemed to refer to the diminishing volume over time (he referred to the PIOMAS volume data and/or the model of Maslowski that apparently showed a similar trend). However, in 2016 he referred to the diminishing extent to show that the prediction still holds.
That was rather puzzling. First, why change from volume to extent when confirming basically the same prediction? Second, when I first started looking into the global warming issue, an often heard argument from the alarmist side was that, even when the extent looked as it was stabilizing, it was the volume that was most important. This made it seem even more odd to me, that an alarmist prediction would go back to extent figures after relying on volume in the past. That is the reverse of what I expected.
The reason for this shift became clear when I found an explanation of what convinced Wadhams to make the 2015 prediction. It was explained as part of a rebuttal he wrote on March 7, 2012 (the second year that he made the 2015 prediction). Here is how he explained it (my emphasis):
The “Arctic could become ice-free for the first time in more than 100,000 years, claims leading scientist”, that was the surprising title of an article from the Independent. That leading scientist is Peter Wadhams from the university of Cambridge and it was explained that satellite data showed there was just over 11.1 million km2 of sea ice on June 1st this year, compared to the average for the last 30 years of nearly 12.7 km2. Therefor on track to be ice free this year (or next year) for the first time in more than 100,000 years.
That seemed odd to me. I didn’t know that June 1st was such an important date for the Arctic sea ice. My take was that the most important moment was in September, when the extent of ice is at its smallest. When we look at the NSIDC data I indeed noticed that it is lower than usual. But prizes are awarded at the finish, not in the middle of the race and going from 11.1 to 1 million km2 in roughly three months would require quite a steep drop. Not entirely impossible though, in 2012 ice extent dropped from 12.3 on June 1st to 3.4 at its minimum, but then it has to deviate from its current course soon to get from 11.1 to 1 in the same time frame.
Screenshot VTM news of December 15, 2014
It was really surprising to watch on Flemish television the “news” that there is more Arctic sea ice. For skeptics this isn’t really news. This fact is known since 2013. In the meanwhile it was staggering to watch the media keep on regurgitating the 2012 Arctic data. Nice they are catching up, it took them a while.
Trust, yet verify 