Wednesday, January 26, 2011

Arctic Report Card

Somewhat related to the previous post, recent changes in the Arctic the past few years are quite remarkable.

NOAA has developed a nice web site called the Arctic Report Card for tracking environmental change in the Arctic.  The YouTube video below provides a nice summary, although the hypothesized linkage between recent sea-ice loss and cold waves over North America and Europe is a subject of ongoing investigation.

4 comments:

  1. Perhaps similar weather patterns developed during the Medieval warm period that allowed the Vikings to settle Greenland and surrounding areas (as well as the opening of the Northwest Passage). With the strong feedback loop between ice coverage and changes in solar absorption in the Arctic, it seems that this could have easily been the case. Do you know what the current trends are in the Antarctic (for comparison)?

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  2. Trends in Antarctica are summarized in the IPCC reports, chapter 3, available at http://www.ipcc.ch/publications_and_data/ar4/wg1/en/contents.html.

    To quote, "Temperatures over mainland Antarctica (south of 65°S) have not warmed in recent decades (Turner et al., 2005), but it is virtually certain that there has been strong warming over the last 50 years in the Antarctic Peninsula region (Turner et al., 2005."

    See also section 3.6.5 for further discussion of the Antarctic trends and their relationship to the Southern Annular Mode (SAM).

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  3. Some have hypothesized that we may be entering an overall cooling period based on changes in solar activity. If so, it might make sense that continental areas would respond more quickly to these cooling influences, and that thermal inertia of the oceans (plus the ice/albedo feedback loop)would create warm anomalies in certain areas near the end of a climactic warming phase. I think that this hypothesis may have a good deal of validity.

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  4. It is out of my area of expertise, but, to my knowledge, there is no model currently available to reliably predict long-term trends in future solar output, or credible scientific evidence to suggest there will be a significant decrease in the coming century. The well-known sun-spot cycle is quasi-predictable, but even that has thrown us a recent curveball.

    In particular, we are currently emerging from one of the deepest solar minimums of the last 100 years (see http://science.nasa.gov/science-news/science-at-nasa/2009/01apr_deepsolarminimum/), yet 2005 and 2010 are the warmest years in the instrumented record.

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