Andrew Revkin thinks so:
It is hard to interpret this as meaning anything other than the crisis of Arctic Sea ice melting too much and too fast is over. This is an important thing, because the rapid and widespread melting of sea ice in the Arctic seems to be causing a thing called Arctic Amplification, which means in normal human terms that the Arctic is warmer (amplified) than normal. This causes a decrease in the differential between equatorial heat and polar heat in the Northern Hemisphere which seems to change the way the Jet Streams operate which in turn causes Weather Whiplash, where we have days and days of warm air being drawn north into "ridges" under the Jet Stream or colder air being drawn south into "troughs" in the Jet Stream. Our Minnesota Snowy April, the current midwest Heat Wave, severe cold in Siberia a while back, flooding in Central Europe, etc. etc. all are effects of the warped and slow moving waves in the Jet Stream. Climate math seams to explain the warping and stalling of the Jet Stream as a function of Arctic Amplification, and Arctic Amplification is clearly the result of a warmer northern sea which is caused by exposure of the sea to more energy from the sun because the ice is reduced. The ice is reduced because of global warming, and this is positive feedback effect.
If the Arctic Sea ice melt is "on a decent track" than this might mean a) global warming isn't really happening and/or b) the Arctic Sea ice to amplification to jet stream warping and stalling to weather whiplash connection isn't valid. So, that would be important. So let's see if Andy is Revkin the Right or Revkin the Wrong on this one.
Here is a graph of the track of Arctic Sea ice melt for a period of ten years for the first years in which good measurements are available, from the National Snow & Ice Date Center. Since the recent changes in the Arctic post date this time period, we can take this to be more or less "normal."
The black, thicker line along the bottom of these other lines is the average ice track from 1981-2010. Note that the sea ice for this ten year baseline period is almost never below that line. The baseline for "on track" is the average of these ten years, and I'll leave it to you to imagine a line running along the midpoint of the observed ice tracks from 1979 to 1988.
Now, here is the same graph but for the ten year period prior to 2012:
For this later time period, the nature of Arctic Sea ice is fundamentally different than before. This is the period of time that the Arctic Sea has been warming. This is the period of time that Arctic Amplification has becoming more severe. This is the period of time that the weather has been changing. This is the period of time that has been affected by anthropogenic global warming. Sea ice tracks that are within this range are not "on track." They are probably better characterized as "messed up."
The following is the same data showing the ice track from 2012 and the present year to date.
The year 2012 was exceptional. It was the most melty of the measured years. This year, is in fact, "on track" but not "on track" to be normal. It is "on track" to be one of the years in which the melting is excessive, and it is "on track" to contribute to Arctic Amplification. It could be worse. It could look like 2012, or even worse, I suppose. But it is not good.
I know it is hard to see all the lines in these graphs when many are selected for display on the Charctic Interactive Sea Ice Graphing Tool, but the years that are not as melty as the present year are all the years prior to the shift documented above, and 2002, 2003, 2004, 2005, and 2006 from after the shift. So, one way of looking at this year is that it is more or less average for the "new normal." It is "on track" for more weather whiplash.
It is actually good news that the Arctic Sea Ice melting is not worse this year than last year, or even as bad this year as some previous years. But it takes a bit of imagination, or perhaps serves some intent that I find difficult to fathom, to suggest that this year things in the Arctic are on a decent track. Arctic Sea ice melt this year is not decent.
And, all this is about sea ice coverage. There is a more severe problem happening that these graphs don't show; the melting of old ice, ice that is thicker, with multiple years all jammed up into thicker ice, has been severe over recent years. This ice is important because it forms the foundation on which new sea ice forms every year. Even if the climate went back to "normal" because some technology was invented that sucked all the extra Carbon Dioxide out of the atmosphere to return us to pre-industrial levels was implemented, the lack of old ice would mean that regeneration of sea ice in the Arctic each year would be difficult, and it would probably take several year get the Arctic Sea back to a decent track. For a change.
Here's Mike Mann's tweet response to Revkin's tweet, which says the same thing I say in this blog post but in fewer than 140 characters:
(Professor Mann's link is to the same data source I use above.)
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Sea ice extent as it appeared in the 1990 IPCC report...
Gee, looks like it made a nice comeback right before the rest of the satellites went up. Are you operating under the assumption that Arctic ice never varied before 1979? What is normal? The weather sucked worldwide when ice was at it's peak, it was too cold, too dry. We are currently seeing greatly reduced hurricane and tornado activity while Arctic ice is at this level. Why would we want it to increase? Why is it that Antarctic ice and Arctic ice seesaw back and forth?
We are not seeing greatly reduced hurricane or tornado activity. The total land area in the US affected by tornados is double over the last decade compared to the prior decade. The number and severity of hurricanes has crept up over the decades and there is good reason to believe that will continue. It was not too dry before the widespread droughts we are experiencing now. It was not too cold before the widspread cold snaps or too hot before the widespread heatwaves that come ultimately from the AA caused by the free ice.
Your use of out dated information is telling. Enjoy the nice cherries you've been picking.
And, really, read the About page for why you are not commenting here again.
There are various ways of interpreting data. A year ago, the sea ice minimum was far lower than extrapolation of trend would have suggested. This was due to an unusually large and prolonged storm. This year the higher ice extent than expected due to changes in the gulf stream. So we have two years of outliers due to natural factors due to a trend that is allegedly caused by human-caused warming.
A counter-hypothesis is that the minimum extent of Arctic sea ice is a partly a lagged function of surface air temperatures (the other variables including water temperatures, wind direction and average wind velocity). This could either be a turning point or a new equilibrium. A couple of (possible) outliers are insufficient to draw any conclusions about underlying trends.
Kevin, you may have missed the point of this post. Yes, last year was an outlier, different from all other previous years. This year is average when compared to the last decade during which we seem to have a new pattern of ice melting. Revkin's assertion seems to be that this year is "normal" but there is nothing "normal" about Arctic Sea ice at present or for the last several years. This year is not an outlier, it is typical of a year in which a very large amount of ice melts, which has happened every year without fail for well over a decade.
#1, see here
"This was due to an unusually large and prolonged storm."
The research doesn't support that view. From "The impact of an intense summer cyclone on 2012 Arctic sea ice retreat" (Zhang et al, 2013):
 This model study examines the impact of an intense early August cyclone on the 2012 record low Arctic sea ice extent. The cyclone passed when Arctic sea ice was thin and the simulated Arctic ice volume had already declined ~40% from the 2007–2011 mean.
The thin sea ice pack and the presence of ocean heat in the near surface temperature maximum layer created conditions that made the ice particularly vulnerable to storms. During the storm, ice volume decreased about twice as fast as usual, owing largely to a quadrupling in bottom melt caused by increased upward ocean heat transport.
This increased ocean heat flux was due to enhanced mixing in the oceanic boundary layer, driven by strong winds and rapid ice movement. A comparison with a sensitivity simulation driven by reduced wind speeds during the cyclone indicates that cyclone-enhanced bottom melt strongly reduces ice extent for about 2 weeks, with a declining effect afterward.
The simulated Arctic sea ice extent minimum in 2012 is reduced by the cyclone but only by 0.15 × 106 km2 (4.4%).
Thus, without the storm, 2012 would still have produced a record minimum.
The cyclone clearly had an effect, but it doesn't seem to be the cause of a record low.
Right. The storm was a proximate determinant in a rapid drop of surface ice measurement for a variety of reasons. I've mentioned this elsewhere ...
But storms come and go and as they do so they influence the positioning and melting of ice in the short term. Generally storms actually have the opposite longer term effect ... more storms means less melting, but they can push the ice around so you get more < 15% quadrants in the sampling. The squiggily wiggily aspect of these lines (if you look close and squint) shows increased rate of melting followed by decreased rate of melting, back and forth, over time. Winds, storms, etc. cause this wigglyness. It is part of the process.
There are storms in the arctic. They can move around ice. They are a continuous factor. Saying that surface ice measurements that drop more quickly for a week because of a strorm does not count is roughly like saying that rainfall that hits the ground because it was pulled there by gravity does not count.
Meanwhile, yes, as Physicist-retired points out, the big storm thing that happened in 2012 did not influence the overall shape of the graph, or not much anyway.
You cannot call the ice minimum years "outliers". An "outlier" can be outside 3-sigma limits. If you plot the August ice averages, you will see they fall along a decreasing linear slope, with the 2013 observation will within 2-sigma limits of expectation.
A new minimum seems to be happening every 2 to 7 years (since the 1990s), with the general trend decreasing. We should expect the next minimum in 2017 or 2018.
Good post, Greg. When I first heard the "news," I was hopeful, but not expecting any real positive news. This seems to confirm that a healthy dose of skepticism (realism? pessimism?) is due with respect to the recovery of arctic sea ice.
It's worth noting, however, that Revkin COULD be right: it could be a turning point. We absolutely cannot know that until later. We CAN know that there's no reason to expect it to be a turning point, rather than simply a year that was not as drastic as 2012.
2013 is in much the same territory as more recent years when you look at ice thickness ... http://psc.apl.washington.edu/wordpress/wp-content/uploads/schweiger/ic…
or volume ... http://psc.apl.washington.edu/wordpress/research/projects/arctic-sea-ic…
But there are reasons to not expect it to be a turning point.
"We CAN know that there’s no reason to expect it to be a turning point,"
Not sure if you were responding to #10, or me at #9, but you said the same thing. ;)
It's a little like saying that if a little airplane crashed it did not really crash because last week a big airplane crashed.
Melting of arctic ice is a natural process, but it has been badly triggered by the humans' industrial activities. In a era of super computers, it is interesting to that man is facing those problems which were otherwise were not more than blessing for the humanity.
Arctic sea ice shrinks to sixth-lowest extent on record
Arctic sea ice "recovers" to its 6th-lowest extent in millennia
This must be the same definition of "recovery" certain ideologues are using when referring to the economy.
"When I use a word," Humpty Dumpty said, in rather a scornful tone, "it means just what I choose it to mean- neither more nor less."
Re: #13: no, it's not. Not even a little.
"There's no reason to expect it to be..." is 100% analogous to "There are reasons to not expect it to be..." Both involve exactly one negative. Neither statements are contradictory, not in the slightest. You are stating that there are reasons to believe that it is not a recovery. I stated that there are no reasons to believe that it is a recovery.
Semantically, yes, there's a difference: you're saying there is POSITIVE proof that things are BAD, whereas I'm saying there is NO proof that things are GOOD. Both, however, mean that things are bad, no matter how you slice it. I'm not sure how the plane analogy fits into that, because in that analogy, the statements are contradictory.