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Arctic Sea Ice Rallies a Bit

radioweather writes "Like the recent stock market rebound, Arctic sea ice is making a big rally over the record low set last year. According to the Alaskan IARC-JAXA website, satellite data which shows sea ice extent as of 10/14/08 was 7,064,219 square kilometers, when compared to a year ago 10/14/08 it was 5,487,656 square kilometers. The one-day gain between 10/13/08 and 10/14/08 of 3.8% is also quite impressive. On May 5th, The National Snow and Ice Data Center suggested the possibility of an ice-free north pole in 2008, but so far, this year has been a banner year for sea ice recovery."

7 of 152 comments (clear)

  1. Re:Wait... by Rei · · Score: 5, Informative

    No, and they're being *deliberately* misleading. Arctic sea ice this year hit the second lowest level in recorded history. Last year was the lowest.

    Arctic sea ice extent during the 2008 melt season dropped to the second-lowest level since satellite measurements began in 1979, reaching the lowest point in its annual cycle of melt and growth on September 14, 2008. Average sea ice extent over the month of September, a standard measure in the scientific study of Arctic sea ice, was 4.67 million square kilometers (1.80 million square miles) (Figure 1). The record monthly low, set in 2007, was 4.28 million square kilometers (1.65 million square miles); the now-third-lowest monthly value, set in 2005, was 5.57 million square kilometers (2.15 million square miles)./I.

    To report values now, from *October*, during the refreeze is just bloody ridiculous. Yes, different years melt and refreeze at different times; there's a lot of spring and fall fluctuation. What matters are the maximum and minimum extents.

    FYI, arctic sea ice normally low in years after El Nino winters and high in years after La Nina winters. Winter of 2006-2007 was in El Nino conditions, leading to the record 2007 melt. But winter of 2007-2008 was in a strong La Nina. The fact that we got the second lowest ice extends on record despite this is incredibly disturbing.

    --
    If I ever become wealthy and mad, I'll leave Companion Cubes on desert islands for shipwreck survivors.
  2. Re:Cold is on the way... by moosesocks · · Score: 5, Insightful

    Solar output and atmospheric heat retention are two completely independent variables.

    The fact that one is rising, while the other is falling is merely a fortunately coincidence.

    My own personal view is that there's a heck of a lot that we don't know about the mechanics of the atmosphere. Until we figure everything else out, though, it's probably a good idea to err on the side of caution.

    --
    -- If you try to fail and succeed, which have you done? - Uli's moose
  3. Re:THIS IS A SLASHDOT NEWS FLASH! by Rei · · Score: 5, Insightful

    I think it's cute how people like you think that the IPCC is either unaware of or deliberately ignoring papers like this ;)

    Seriously -- read the report some time. It'll be educational for you. There's something like 50 papers referenced for just sunspots alone. If it A) has to do with global warming, even tangentially, and B) was published in a peer-reviewed journal in the past 10-20 years, odds are it's in there.

    Science does not work in a manner of "this one paper says one thing about one aspect, so it must be God's honest truth!". The amount of research out there is pretty staggering. It is... let's just say "unfortunate" that the popular press has a habit of picking up one work or another and sensationalizing them.

    --
    If I ever become wealthy and mad, I'll leave Companion Cubes on desert islands for shipwreck survivors.
  4. Re:Cold is on the way... by Rei · · Score: 4, Informative

    Once again, this is why people who don't know anything about a topic shouldn't comment on it.

    Earth's oceans, especially the Pacific, are truly massive heat reservoirs, and changing how they interact with the atmosphere can strongly affect the atmosphere's temperature in the *short term*. In the long term, the planet is still dominated by its radiation balance, of course.

    The linked article was describing, quite accurately, how the early part of this year was in La Nina conditions. El Nino is caused by the weakening or reversal of the Walker circulation (an atmospheric flow around the Equator). The Walker circulation helps encourage the upwelling of cold waters in the eastern Pacific, so El Nino conditions prevent more of this cool water from reaching the surface. As a net change, the equatorial Pacific ends up much warmer on the surface, raising atmospheric temperatures. In La Nina conditions, the situation is reversed; a stronger Walker circulation encourages more upwelling, and thus colder surface (and hence atmospheric) temperatures.

    This has *absolutely nothing* to do with the planet's long-term temperature, which even a six year old looking at a graph could recognize through the year-to-year noise.

    Now, if you *really* want a breakdown of how it ranked (records since 1880), here you go (remember that the first half of this year was in strong La Nina conditions!):

    January: 31st warmest
    February: 15th warmest
    March: Warmest for land on record, 13th warmest for ocean
    April: 13th warmest
    May: 8th warmest
    June: 8th warmest
    July: Tied for 5th warmest
    August: 10th warmest
    September: Tied for 9th warmest

    Spring: 7th warmest
    Summer: 9th warmest
    January to July: 9th warmest

    --
    If I ever become wealthy and mad, I'll leave Companion Cubes on desert islands for shipwreck survivors.
  5. Re:Cold is on the way... by NotmyNick · · Score: 5, Insightful

    Ironic isn't it that some people who so easily dismiss decades of research by thousands of scientists will so willingly glom onto one report that might ever so slightly support their lifestyle choice?

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    Notmysig
  6. Re:THIS IS A SLASHDOT NEWS FLASH! by Ambitwistor · · Score: 4, Informative

    Seriously, I wish people would stop getting so shocked about this.

    Climatologists are not unaware that the climate has changed in the past. The issue is that climate is currently changing faster than it would have without human input, and that larger and faster changes are likely if we continue to increase our input to the climate system.

  7. Re:Cold is on the way... by Ambitwistor · · Score: 4, Insightful

    If I'm told to err on the side of caution, do you know what I would do? Nothing!

    You're driving in complete darkness and someone tells you there might be a cliff nearby. You're told to err on the side of caution. What do you do? Speed up? I think not. You stop, or at least slow down.

    Right now CO2 levels are already higher than they've been in at least a million years, and we're increasing them at an accelerating pace. Basic physics as well as our observations of present and past climate suggest that this will lead to warming, possibly by a dangerous amount.

    Continuing to add CO2 at an accelerating pace may be "doing nothing different", but it is not "doing nothing". It is doing a very significant Something.

    We don't know everything about the climate, but we know that reducing CO2 back to pre-industrial levels is unlikely to do anything worse than keep us at the present climate (and even then we are likely to still warm a little due to heat already stored in the ocean). By contrast, there are a lot of climate risks associated with staying on our current emissions trajectory.