2015 Antarctic maximum sea ice extent breaks streak of record highs

2015 Antarctic maximum sea ice extent breaks streak of record highs
Credit: NASA

The sea ice cover of the Southern Ocean reached its yearly maximum extent on Oct. 6. At 7.27 million square miles (18.83 million square kilometers), the new maximum extent falls roughly in the middle of the record of Antarctic maximum extents compiled during the 37 years of satellite measurements - this year's maximum extent is both the 22nd lowest and the 16th highest. More remarkably, this year's maximum is quite a bit smaller than the previous three years, which correspond to the three highest maximum extents in the satellite era, and is also the lowest since 2008.

The growth of Antarctic sea ice was erratic this year: sea ice was at much higher than normal levels throughout much of the first half of 2015 until, in mid-July, it flattened out and even went below normal levels in mid-August. The sea recovered partially in September, but still this year's maximum extent is 513,00 square miles (1.33 million square kilometers) below the record maximum extent, which was set in 2014. Scientists believe this year's strong El Niño event, a natural phenomenon that warms the surface waters of the eastern equatorial Pacific Ocean, had an impact on the behavior of the sea ice cover around Antarctica. El Niño causes higher sea level pressure, warmer air temperature and warmer sea surface temperature in the Amundsen, Bellingshausen and Weddell seas in west Antarctica that affect the sea ice distribution.

"After three record high extent years, this year marks a return toward normalcy for Antarctic sea ice," said Walt Meier, a scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "There may be more high years in the future because of the large year-to-year variation in Antarctic extent, but such extremes are not near as substantial as in the Arctic, where the declining trend towards a new normal is continuing."

This year's maximum extent occurred fairly late: the mean date of the Antarctic maximum is Sept. 23 for 1981-2010.

Antarctic sea ice likely reached its annual maximum extent on Oct. 6, barring a late season surge. This video shows the evolution of the sea ice cover of the Southern Ocean from its minimum yearly extent to its peak extent. Credit: NASA's Goddard Space Flight Center

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Oct 15, 2015
ut such extremes are not near as substantial as in the Arctic, where the declining trend towards a new normal is continuing.


What's with leftist spokespeople not being able to give even one press release without telling a lie?

The arctic hasn't lost ice in 3 years. In fact, volume actually increased.

Oct 15, 2015
Declassified Spy Maps Show Melting Arctic Ice

http://www.smiths.../?no-ist

Oct 15, 2015
September volume minimum was higher than 4 of the previous years, though a tad lower than last year.

http://psc.apl.uw...1_CY.png

Neven has to invent a crisis over on his site, because there's nothing scientific to talk about in his alarmist favor this year. He's resorted to mocking people with opinion polls.

Last year, or was it the year before last, he said he hoped one of the oil tankers in the arctic would crash just for the heck of it to make the oil companies look bad.

That's what these alarmists have resorted to .

You know, I actually care about this stuff, believe it or not. I just disagree on what's causing it to happen.

Right now the ice volume has had a mini-rebound last year and then a slight down this year, but it's still up from 2 and 3 years ago.

Oct 15, 2015
The growth of Antarctic sea ice was just a short-term impact of global warming. There was always going to be a point when the impact of the land-ice melt and the warming-induced changes in Antarctic winds were going to be overtaken by increases in land and sea temperatures.

So this is less "remarkable" and more like "what we were expecting, really".

Apropos of the comment section - anyone who thinks Arctic sea ice is expanding can't read.

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