Thin ice and the importance of Quaternary geology

From NASA Earth Observatory:

2011 Sea Ice Minimum

From the description (emphasis added):

In September 2011, sea ice covering the Arctic Ocean declined to the second-lowest extent on record. Satellite data from NASA and the National Snow and Ice Data Center (NSIDC) showed that the summertime ice cover narrowly avoided a new record low.


Melt season in 2011 brought higher-than-average summer temperatures, but not the unusual weather conditions that contributed to the extreme melt of 2007, the record low. “Atmospheric and oceanic conditions were not as conducive to ice loss this year, but the melt still neared 2007 levels,” said Walt Meier of NSIDC. “This probably reflects loss of multi-year ice in the Beaufort and Chukchi seas, as well as other factors that are making the ice more vulnerable.”

The low sea ice level in 2011 fits the pattern of decline over the past three decades, said Joey Comiso of NASA’s Goddard Space Flight Center. Since 1979, September Arctic sea ice extent has declined by 12 percent per decade.

“The sea ice is not only declining; the pace of the decline is becoming more drastic,” he noted. “The older, thicker ice is declining faster than the rest, making for a more vulnerable perennial ice cover.”

While the sea ice extent did not dip below the record, the area did drop slightly lower than 2007 levels for about ten days in early September 2011. Sea ice “area” differs from “extent” in that it equals the actual surface area covered by ice, while extent includes any area where ice covers at least 15 percent of the ocean.

Arctic sea ice extent on September 9, 2011, was 4.33 million square kilometers (1.67 million square miles). Averaged over the month of September, ice extent was 4.61 million square kilometers (1.78 million square miles). This places 2011 as the second lowest ice extent for both the daily minimum and the monthly average. Ice extent was 2.43 million square kilometers (938,000 square miles) below the 1979 to 2000 average.

Climate models have suggested that the Arctic could lose almost all of its summer ice cover by 2100, but in recent years, ice extent has declined faster than the models predicted.

A few years back, I blogged about a report that the Arctic Ocean may have been ice-free around 6000-7000 years ago, so this may be a natural cycle. Or it may be caused by human-induced global warming. I don’t know. I ended that post with the following:

I’m not a global warming denier, which bothers some of my friends. I do believe that human activities are affecting Earth’s climate. This does point out, however, the importance of geological studies of Quaternary (ice age to present) climate systems. Whatever is happening today, even if caused by humans, can only be fully understood in its geological context.

Grace and Peace

8 thoughts on “Thin ice and the importance of Quaternary geology

  1. Virginia Peterson

    If you haven’t seen it, the latest National Geographic magazine (Oct.) has an article “World without ice”. It’s about the Paleo-Eocene Thermal Maximum (56 million years ago), when a massive dose of carbon dioxide was released into the atmosphere and caused a lot of warming.


  2. Martin_Lack

    Dear Kevin,

    I have just stumbled upon your blog on the WordPress Environment tag page; and just had to read it…. I grew up going to an Anglican church but did not become a Christian until I left home do a Geology Degree. That was over 25 years ago and an awful lot has happened since (see the About, Background and History pages on my blog) but, to cut a long story short, I have now done an MA in Environmental Politics and am trying to help save the planet from the excesses of human greed, arrogance, selfishness and pride.

    Presumably you would beloing to the “Good Stewardship” camp rather than the “Dominate and Subdue” camp within Evangelical Christianity? Also, although I did have a quick look at the Chicago Statement I could not find any clear indication of your position on the age of the Earth? Either way, I wish you all the best in your quest to decouple Evangelical Christianity from the Tea Party.

    Kind regards,



  3. geochristian


    Left vs. right can be rather confusing. I am rather conservative on some issues, and not so on others. Many conservatives don’t give a hoot about the environment or social justice, and many liberals care deeply about those issues but come up with awful solutions.

    I am certainly not a YEC (take a look at my bio or my Six bad answers from Answers in Genesis series.

    Even the “good stewardship” label is something that is often abused within Evangelicalism. The God-woundn’t-have-given-us-oil-if-we-weren’t-supposed-to-use-it-all-and-it-will-never-run-out movement within Christianity can hide behind slogans of good stewardship, but I don’t think using all of a resource within a span of a few generations is what stewardship is all about. True Biblical stewardship looks at all of Genesis 1 (a world teeming with wildlife, for example), not just at a distorted view of human rule over the creation.

    Thanks for commenting.


  4. Martin_Lack

    Hi Kevin.

    Thanks for clarifying the YEC thing. I am so pleased. We seem to have much in common. If you plough your way through About, Background, and History and then pop over to my old Falsifiable Theology site on Blogger (not being maintained), you will see what I mean! However, to summarise: I went off to study Geology at the age of 18 already convinced that YEC could not possibly be right then, after a year away from home, I discovered what Christianity was really all about and so became very anti-evolution. It has taken me over 25 years to reach the point of possibly being ambivalent towards evolution; but I remian very much opposed to those for whom evolution and/or science has become a form of religious belief itself.

    I guess my problem with the anti-environmental wing of Christendom is the parallels I can see with those St Paul criticised for complete apathy and inaction because they had decided that Jesus was going to return very soon. They were, as my Grandma used to say, “too heavenly-minded to be of any earthly-use!“…

    I hope we can stay in touch.


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