Arctic Ice, Pre-Obit

Below, the opening paras of an excellent article in Think Progress/ Climate Progress. You can read the full piece here.

Why The Arctic Sea Ice Death Spiral Matters

By Joe Romm on Aug 26, 2012 at 12:25 pm

Arctic sea ice extent takes a nosedive this year. What does it mean for us? (Source: Japan Aerospace Exploration Agency)

By Neven Acropolis with Kevin McKinney

In the past week the Arctic sea ice cover reached an all-time low, several weeks before previous records, several weeks before the end of the melting season. The long-term decline of Arctic sea ice has been incredibly fast, and at this point a sudden reversal of events doesn’t seem likely. The question no longer seems to be “will we see an ice-free Arctic?” but “how soon will we see it?”. By running the Arctic Sea Ice blog for the past three years I’ve learned much about the importance of Arctic sea ice. With the help of Kevin McKinney I’ve written the piece below, which is a summary of all the potential consequences of disappearing Arctic sea ice.

Arctic sea ice became a recurrent feature on planet Earth around 47 million years ago. Since the start of the current ice age, about 2.5 million years ago, the Arctic Ocean has been completely covered with sea ice. Only during interglacials, like the one we are in now, does some of the sea ice melt during summer, when the top of the planet is oriented a bit more towards the Sun and receives large amounts of sunlight for several summer months. Even then, when winter starts, the ice-free portion of the Arctic Ocean freezes over again with a new layer of sea ice.

Since the dawn of human civilization, 5000 to 8000 years ago, this annual ebb and flow of melting and freezing Arctic sea ice has been more or less consistent. There were periods when more ice melted during summer, and periods when less melted. However, a radical shift has occurred in recent times. Ever since satellites allowed a detailed view of the Arctic and its ice, a pronounced decrease in summer sea ice cover has been observed (with this year setting a new record low). When the IPCC released its Fourth Assessment Report in 2007, it was generally thought that the Arctic could become ice-free somewhere near the end of this century. But changes in the Arctic have progressed at such speed that most experts now think 2030 might see an ice-free Arctic for the first time. Some say it could even happen this decade.

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2 Responses

  1. Poo says:

    I admit to some surprise that anyone reads anything published by the horribly flawed and corrupt IPCC.
    That said, I believe the term “dawn of human civilization” wants some defining. Our growth from pollywogs to pill popping ninnies and planet colonizers has been but a finger snap in time when compared to the estimated age of the Earth itself. Archeologists estimate that we upright humans have been on the Earth for about 200,000 years, give or take.
    We are a proud member of a species of bipedal primates in the family Hominidae. Not a family name I recognize but who am I to argue. We’re all, you and I included, homo sapiens. This is Latin for “wise human”. I like the sound of that. It means we, or some of us at least, have a highly developed brain, a bipedal gait, and opposable thumbs. That’s me all right. You too.

    The common archiologist’s timeline puts we humans originating about 200,000 years ago in southern Africa. They call this the Middle Paleolithic Period. Some 70,000 years ago, our ancestors migrated out of Africa and began colonizing the world, such as it was. No doubt they arrived in Luxembourg early on. Canada was a long time waiting to be civilized. These same archiologists claim these ancestors spread to Eurasia and Oceania 40,000 years ago. They didn’t reach the Americas till some 14,500 years ago. Proof positive that you were civilized long before me. Was it ever in question?

    Once upon a time, about 1/3 of the earth was ice which was fine by my people as they played hockey, a lot. As the earth started warming up the ice started to melt then it froze and melted again. There have been at least 5 major ice ages and countless minor ice ages over the last 2.5 Billion Years. They and the ensuing warming periods have all been well documented in sedimentary records. The earth is an open book for those of us capable of reading it.
    Sadly, Christian Fundamentalists of the left and right neither understand nor accept the most rudimentary concepts of Physical Geography and Radiometric and Relative Dating processes. They believe that the Earth is less than 6,000 years old and any other solution is the work of the Devil or a bunch of wooly mammoths. The last major Glacial Period (Ice Age) was 10,000 to 12,000 years ago depending on your archiologist. My people, being hockey players in temperament and intellectual capacity, prefer 12,000. The current Holocene Epoch (warming period) has been occuring ever since.
    Long after my death and presuming the Chinese and Indians keep buiding coal fired power plants unabated and the 3rd world burns whatever they have to in order to survive and improve their standard of living, long after there will be good farming throughout areas previously thought uninhabitable. Either that or the earth and universe will do what it pleases neither distracted nor interested in what any of us “wise humans” has to say.
    In the meantime, bundle up. Those satellites, weather balloons and Farmer’s Almanacs predict a blisteringly cold winter. I’m not worried whether the Northwest Passage will be frozen or open as it has been 4 times in the last 100 years. I’m more concerned that wee me will freeze over. Brrrrrrrrrrrrrr!

    or about a million years. About 10,000 years ago the earth started to melt.

  2. Poo says:

    Last 2 lines inexplicably out of order. Should have been deleted as they were incorporated into 10-12. Oops.

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