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Sea Ice Extent Sinks To Record Lows At Both Poles (sciencedaily.com)

According to NASA, Arctic sea ice appears to have reached on March 7 a record low wintertime maximum extent. On the opposite side of the planet, Antartica ice hit its lowest extent ever recorded by satellites (since satellites began measuring sea ice in 1979) on March 3 at the end of summer in the Southern Hemisphere. Science Daily reports: Total polar sea ice covered 6.26 million square miles (16.21 million square kilometers), which is 790,000 square miles (2 million square kilometers) less than the average global minimum extent for 1981-2010 -- the equivalent of having lost a chunk of sea ice larger than Mexico. The ice floating on top of the Arctic Ocean and surrounding seas shrinks in a seasonal cycle from mid-March until mid-September. As the Arctic temperatures drop in the autumn and winter, the ice cover grows again until it reaches its yearly maximum extent, typically in March. The ring of sea ice around the Antarctic continent behaves in a similar manner, with the calendar flipped: it usually reaches its maximum in September and its minimum in February. This winter, a combination of warmer-than-average temperatures, winds unfavorable to ice expansion, and a series of storms halted sea ice growth in the Arctic. This year's maximum extent, reached on March 7 at 5.57 million square miles (14.42 million square kilometers), is 37,000 square miles (97,00 square kilometers) below the previous record low, which occurred in 2015, and 471,000 square miles (1.22 million square kilometers) smaller than the average maximum extent for 1981-2010.

5 of 211 comments (clear)

  1. Re:Similar by serviscope_minor · · Score: 5, Informative

    My interest levels of sea ice have gotten to an all time record low as well.

    Science is nerdy, climate records are science news. And the climate changing does in fact matter. I would say that such an article ticks all boxes of "news for nerds, stuff that matters".

    If you don't like hearing about it, feel free to go to another website or simply not read and comment on the article.

    --
    SJW n. One who posts facts.
  2. Re:Sea ice extent in Medieval Warm Period? by silentcoder · · Score: 4, Informative

    The medieval warm period did not affect sea ice at all. It also did not affect the global temperature at all. It was a localized effect in such a small area that the global average didn't even move.

    Nope, nothing like this has ever happened before.

    --
    Unicode killed the ASCII-art *
  3. Re:Fake news, see the MASIE data for yourself by Anonymous Coward · · Score: 5, Informative

    Yes, because when dealing with a complex topic, rather than listening to professionals and peer-reviewed research, I like to play amateur scientist and get all my info from blogs.

    FYI, you can make your own comparison graphs here. On the about page it has links to all of the datasets, which you can download: Sea Ice Index, Near-Real-time DMSP SSM/I-SSMIS Daily Polar Gridded Sea Ice Concentrations, and the NASA-produced Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I Passive Microwave Data.

    As for MASIE:

    2. When should I use MASIE and when should I use the Sea Ice Index?

    Use the Sea Ice Index when comparing trends in sea ice over time or when consistency is important. Even then, the monthly, not the daily, Sea Ice Index views should be used to look at trends in sea ice. The Sea Ice Index documentation explains how linear regression is used to say something about trends in ice extent, and what the limitations of that method are. Use MASIE when you want the most accurate view possible of Arctic-wide ice on a given day or through the week.

  4. Re:20,000 years ago by Fire_Wraith · · Score: 4, Informative

    You're not wrong about the past glacial extent. And no, the glaciers didn't disappear because of humanity, they receded well in advance of the first permanent human settlements (roughly the dawn of civilization, though humans were around well before that). And interestingly enough, global temperatures were in a (slow) cooling trend from about 7000BCE onward.

    But that stopped around 1900, and the global temperature average has begun to swing sharply, at a rate that ought to be alarming, because as the graph shows, it is quite literally without precedent, in terms of the speed of the change, and shows no signs of stopping unless we take action to affect it:
    https://xkcd.com/1732/

  5. Re:Sea ice extent in Medieval Warm Period? by angel'o'sphere · · Score: 5, Informative

    The medieval warm period did not affect sea ice at all.
    Probably.

    It also did not affect the global temperature at all.
    On your weird definition of global?

    It was a localized effect in such a small area that the global average didn't even move.
    No it wasn't. We just have no data about the _global_ temperature at that time, but we have reports from many places of the world, notable China and Japan that it was warmer than normal there, too. So: very likely it was at least on the northern hemisphere a global phenomenon.

    So: the lack of written evidence, because we have none from Inka, Australians, Africans, does not mean it did not happen there.

    And: if you talk about a/the medieval warm period, it would be cool to add which one you mean. There where three AFAICT.

    --
    Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.