End-of-summer Arctic sea ice extent is eighth lowest on record

End-of-summer Arctic sea ice extent is eighth lowest on record

Arctic sea ice appeared to have reached its yearly lowest extent on Sept. 13, NASA and the NASA-supported National Snow and Ice Data Center (NSIDC) at the University of Colorado Boulder have reported. Analysis of satellite data by NSIDC and NASA showed that at 1.79 million square miles (4.64 million square kilometers), this year's Arctic sea ice minimum extent is the eighth lowest in the consistent long-term satellite record, which began in 1978.

Arctic sea ice, the layer of frozen seawater covering much of the Arctic Ocean and neighboring seas, is often referred to as the planet's air conditioner: its white surface bounces solar energy back to space, cooling the globe. The sea ice cap changes with the season, growing in the autumn and winter and shrinking in the spring and summer. Its minimum summertime extent, which typically occurs in September, has been decreasing, overall, at a rapid pace since the late 1970s due to warming temperatures.

This year, temperatures in the Arctic have been relatively mild for such high latitudes, even cooler than average in some regions. Still, the 2017 minimum sea ice extent is 610,000 square miles (1.58 million square kilometers) below the 1981-2010 average minimum extent.

"How much ice is left at the end of summer in any given year depends on both the state of the ice cover earlier in the year and the affecting the ice," said Claire Parkinson, senior climate scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The weather conditions have not been particularly noteworthy this summer. The fact that we still ended up with low sea ice extents is because the baseline ice conditions today are worse than the baseline 38 years ago."

Arctic sea ice appears to have reached a record low wintertime maximum extent for 2017, according to scientists at the NASA-supported National Snow and Ice Data Center (NSIDC) in Boulder, Colorado. Observations indicate that on Sept. 13, 2017 ice extent shrunk to the eighth lowest in the satellite record, at 4.64 million square miles, or 1.79 million square miles. Credit: NASA's Scientific Visualization Studio/Helen-Nicole Kostis

The three years with the lowest Arctic ice extents on record —2012, 2016 and 2007— experienced strong summer storms that hammered the ice cover and sped up its melt. "In all of those cases, the weather conditions contributed to the reduced ice coverage. But if the exact same weather system had occurred three decades ago, it is very unlikely that it would have caused as much damage to the sea ice cover, because back then the ice was thicker and it more completely covered the region, hence making it more able to withstand storms," Parkinson said.

On the other side of the planet, Antarctica is heading to its maximum yearly , which typically occurs in September or early October. This year's maximum extent is likely to be among the eight lowest in the satellite record—a dramatic turn of events considering that 2012, 2013 and 2014 all saw consecutive record high maximum extents, followed by a sudden large drop in 2015 and a further although smaller decrease in 2016. So far, the September Antarctic ice extents this year are comparable to those of a year ago.

"What had been most surprising about the changing in the past three decades was the fact that the Antarctic sea ice was increasing instead of decreasing," Parkinson said. "The fact of Arctic sea ice decreases was not as shocking because this was expected with a warming climate, although the overall rate of the decreases was greater than most models had forecast."

Parkinson said that although it is still too early to talk about a long-term reversal in the behavior of Antarctic sea ice, the decreases witnessed in the past two years provide important data to test the various hypotheses that scientists have put forward to explain why Antarctic sea ice coverage had been increasing, overall, between 1979 and 2015.

Adding the Antarctic and Arctic sea ice extents month by month through the satellite record shows that globally the Earth has been losing sea ice since the late 1970s in each portion of the annual cycle of ice growth and decay. "In fact, this year, every single month from January through August experienced a new monthly record low in global sea ice extents," Parkinson said.


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Sep 19, 2017
This article is a prime example of how propaganda is biased. While the figures are true they could have just as well said that the Arctic sea ice has increased 40% from it's 2012 low.

Sep 19, 2017
This article is a prime example of how propaganda is biased. While the figures are true they could have just as well said that the Arctic sea ice has increased 40% from it's 2012 low.

Or say that Artic sea ice is 27% below 1981-2010 median as presented by the National Snow & Ice Data Center. https://nsidc.org...e-graph/
Or Say that in 2017 sea ice has sinked to record low, as reported by NASA. https://www.nasa....th-poles

Sep 19, 2017
MR166, that would be cherry picking.

The point is that even though the conditions this year were relatively mild, the extent of sea ice loss is substantial. This would not have been the case previously and this is what is new. The reason is because of reduced ice thickness. The bottom line is given at the end of the text.

"Adding the Antarctic and Arctic sea ice extents month by month through the satellite record shows that globally the Earth has been losing sea ice since the late 1970s in each portion of the annual cycle of ice growth and decay."

Sep 19, 2017
The post by 166 is a prime example of people fooling themselves to feel better.

Sep 19, 2017
This article is a prime example of how propaganda is biased. While the figures are true they could have just as well said that the Arctic sea ice has increased 40% from it's 2012 low.


Yes, I agree with you MR166. This is a prime example of bias. You would think they would be ecstatic that the Arctic sea ice has increased by a substantial percentage. Will next year be "Arctic sea ice extent is tenth lowest on record"?

Sep 20, 2017
The weather conditions have not been particularly noteworthy this summer. The fact that we still ended up with low sea ice extents is because the baseline ice conditions today are worse than the baseline 38 years ago.

Weather, no. But what I see from the analyses on NSIDC most of the ice missing is on the Pacific side, and north Pacific has had a strong warm anomaly for some reason recently.

Sep 20, 2017
This article is a prime example of how propaganda is biased. While the figures are true they could have just as well said that the Arctic sea ice has increased 40% from it's 2012 low.


Yes, I agree with you MR166. This is a prime example of bias. You would think they would be ecstatic that the Arctic sea ice has increased by a substantial percentage. Will next year be "Arctic sea ice extent is tenth lowest on record"?

Agreeing with your own socks won't improve your stance ;)

Sep 20, 2017
"damage to the sea ice cover"

Kinda says it all. If the ice melts, it's damage.

Meanwhile, where on this site is the story, reported yesterday in major media, that the amount of predicted global warming has been over-estimated by the climate models, according to a new analysis by the climate modelers?

And if CO2 is the driver for ice melting, and CO2 is at levels not seen in millions of years, why is there ANY ice left at the North Pole? Isn't the so-called "global average temperature" supposed to track CO2 upwards, in a closely coupled fashion? Shouldn't the ice be lower now than ever before (in the 40-year satellite record)?

Where is James Hansen's apology, for yanking everyone's chain these past 50 years --- first with the "global cooling" catastrophe he "foresaw" back at the end of the last cooling cycle (the mid '70s), then with the "global warming" catastrophe he's been touting ever since? Can I have back all the money I've paid for other people's solar panels?

Sep 20, 2017
James Hansen did to the credibility of Pen State science what another well known figure did to the credibility of their football team.

Sep 21, 2017
This article is a prime example of how propaganda is biased. While the figures are true they could have just as well said that the Arctic sea ice has increased 40% from it's 2012 low.


Yes,This is a prime example of bias. You would think they would be ecstatic that the Arctic sea ice has increased by a substantial percentage. Will next year be "Arctic sea ice extent is tenth lowest on record"?


Except that unlike you they understand statistics. Regression to the mean is a thing. Ice extent is analysed in decadal batches for a reason. Arctic sea ice has declined approx 13% per decade since the late 1970s. That is what we call actual science rather than the crappy cherry picking deniers are so fond of.

There's a reason I mock this argument with "Arctic ice increased since 3pm last Tuesday'. It's that ridiculous.

PS - low base % increase. That is all.
https://dameholly...-denial/

Sep 21, 2017
" Arctic sea ice has declined approx 13% per decade since the late 1970s."

I realize that the late 70s was that start of satellite measurements but that does not negate the fact that it was also a time of peak ice in relation to other preceding decades.

Sep 21, 2017
" Arctic sea ice has declined approx 13% per decade since the late 1970s."

I realize that the late 70s was that start of satellite measurements but that does not negate the fact that it was also a time of peak ice in relation to other preceding decades.


By what source? I love how you are forced to concede a point and then instantly shift the goalposts. So you concede that Arctic sea ice IS declining, right? I mean, you've been forced to. Just say "sorry, I was wrong".

Sep 21, 2017
" So you concede that Arctic sea ice IS declining, right?"

I have no problem agreeing that there has been a decline since the 70s, it is just the unprecedented part I have problems with.

Sep 27, 2017
The post by 166 is a prime example of people fooling themselves to feel better
-as opposed to george kamburoff the lying cheating psychopath who fools other people to feel better.

More insight.

Oct 02, 2017
I agree with other comments here. What about some positive attitude. The Arctic was predicted to be ice free by 2013, then 2015. It hasn't happened and if anything, it's showing signs of stability. Arctic records only go back about 60 years, and only 38 years for satellite records, so we really have little idea of what to expect long term. Right now, both Arctic and Antarctic ice are within two standard deviations of the long term average - I would have thought this was good news.

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