Why Should We Care About the Cryosphere?

Since the majority of people in the world do not enjoy living on areas covered by ice and snow, it is no wonder that the cryosphere remains relatively unknown despite its large size and contribution to global climate.  The extent of the cryosphere is made up by all the regions of the world where water is in solid form—ice, snow, glaciers, permafrost or icebergs—ranging from the enormous ice sheets in Antarctica and Greenland to the rapidly disappearing glaciers of mountainous regions.  The size and makeup of the cryosphere has changed quite a lot in the past, oscillating with global temperatures to cause the poles warming to subtropical habitat or cooling to cover the present day United States in ice (NCAR, 2008).  While the size of the cryosphere also changes seasonally with melting in the summer and freezing in the winter, comparing recent trends to historical data show that the retreating glaciers and thinning ice sheets of the cryosphere could be an indicator of global climate change (NCAR, 2008).

Climate scientists have turned their attention to the sea ice extent in the Arctic because it has such a large effect on global climate.  This is largely due to the high albedo of snow and ice, or its ability to reflect sunlight.  For example, the white crystals of freshly fallen snow have an albedo of between 75%  and 95%, meaning they reflect 75-95% of the sunlight that contacts them (NCAR, 2008).   By reflecting most sunlight instead of absorbing it, snow and ice have a cooling effect on the atmosphere (NCAR, 2008).  Sea ice can also alter climate patterns.  As ice forms on the surface it acts as an insulator, reducing movement of moisture and energy from the ocean to the atmosphere.  When the ice melts and leads—or openings in the ice—form, movement is no longer restrained and heat and water are allowed to escape again forming clouds and precipitation (NSIDC, 2009).

Figure provided from the National Snow and Data Center, Boulder, Colorado.

Not only does sea ice effect global climate, it also acts as an indicator of global climate trends.  The spatial extent of the Arctic sea ice varies rapidly in response to changes in climate and weather but has a typical winter extent of 14 to 16 million square kilometers melting to a summer extent of 7 million square kilometers.  Data collected since 1979 has shown that the winter sea ice extent in the Arctic has decreased 4.2 percent per decade (Meier et al. 2006) and this trend has been traced back to 1953 using observations from ice charts and other sources (NSIDC, 2009).  An even more dramatic reduction in ice cover has been observed just in the last decade with a record low minimum extent in September 2007, an astounding 39% below the average from 1979 to 2000 shown in the figure above.  One contributing factor for the low 2007 Arctic sea ice extent was that the ice formed was thinner than in most years, taking less energy to melt (NSIDC, 2009).  Thicker ice tends to form from partially melted ice left from previous years; with the Arctic sea ice receding so significantly it is likely that the sea ice thickness here will continue to decline in the future.  Another factor that contributed was a lengthened melt season, with the spring melt coming earlier and the autumn freezing pushed back later than the average of past years (NSIDC, 2009).

The reduction in Arctic sea ice extent has huge implications for those that do live on the Arctic cryosphere, especially mammals like polar bears and walruses that rely on the annual ice for hunting, feeding and breeding.  Human residents of the Arctic must also react to the changes that are described as “uggianaqtuq”, a North Baffin Inuktitut word meaning to behave unexpectedly.   Mark Serreze, a senior scientist at the National Snow and Ice Data Center believes that sea ice cover is in a downward spiral and we may already be past the point of no return.  Serreze said, “We may well see an ice-free Arctic Ocean in summer within our lifetimes” which scientists agree could happen by 2030 (NSIDC, 2009).  How this will affect global populations and whether this change is the result of human related gas-emissions or a natural cycle is still the subject of much debate.

For current or historical information on the cryosphere follow this link: http://arctic.atmos.uiuc.edu/cryosphere/.

National Snow and Ice Data Center.  (2009). State of the cryosphere: sea ice.  [Accessed on November 21, 2009]  <http://nsidc.org/sotc/sea_ice.html&gt;

National Center for Atmospheric Research.  (2008).  NCAR earth system research: Studying the cryosphere.  [Accessed on November 21, 2009]  <http://www.ncar.ucar.edu/research/earth_system/cryosphere.php&gt;

Meier, W.N., J.C. Stroeve, and F. Fetterer.  (2006). Whither Arctic sea ice? A clear signal of decline regionally, seasonally and extending beyond the satellite record. Annals of Glaciology 46: 428-434.

Polar Sea Ice Cap and Snow – Cryosphere Today.  (2009).  [Accessed November 21, 2009] < http://arctic.atmos.uiuc.edu/cryosphere/&gt;

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~ by kaderhold on November 23, 2009.

4 Responses to “Why Should We Care About the Cryosphere?”

  1. I am not very knowledgeable on this subject so I have a few questions rather than comments. I was wondering, if the problem started in the early 20th century, are we really going to be able to change it? And how do we do that? It just seems like with our industrial ways of living it will be extremely difficult. I apologize for the negative aspect, but I have always felt this is a natural cycle of the earth–especially since I don’t see the earth as a stagnant form or permanent, forever lasting form. I understand that our ways of living are not quite natural and have definitely impacted this progress, but can it really be expected that we completely change our way of living?

    So I tried to educate myself and found these articles to my questions:

    http://talismantol.wordpress.com/2009/10/20/climate-change/
    This article talks about how difficult but worthy it will be to take actions to change the climate change direction.

    (1)Reduce light usage
    (2) Take a walk instead of using cars
    (3) Wash in cold water…what?
    (4) Make good food choices

    I guess my point is, that these will just decrease the impact, not actually reverse it. So how can it be reversed? Can it be reversed? And also, these just seem like so small of things its hard for me to imagine that they have an actual impact on the problem. Besides the fact that some of them are extremely inconvenient and that’s my issue with trying to image humanity actually doing these things for such long-term benefits, in the future benefits.

    Since I obviously don’t understand, I had to go to the child’s version…I really want to understand, care, be inspired to change the climate…but no one or nothing I have read has convinced me yet.

    http://www.epa.gov/climatechange/kids/change.html

    This is really funny because I have just walked you through my though process (even though it may sound/seem/be horrible that I wasn’t too concerned with climate change) but the above article has probably made the most impact on my thoughts about climate change and made me care the most. However, I just still can’t conceive that people will actually give up their comforts and luxuries to change the climate.

  2. I’ve heard that sea ice often contains a high concentration of chemicals that are not found in the atmosphere/water (specifically I’m thinking of carbon dioxide and water-soluble toxins). Is this true and, if so, how might it be affecting the atmosphere/ecology of the sea? Has anyone studied this yet?

  3. This is a really interesting blog! It seems to show more of how global warming is directly affecting the way we live. It seems astounding that there may be an ice-less Artic Ocean within the next two years. What do researches base this information on? It seems a very alarming prediction, and I’m just curious what kind of support they have for this timeline. Also, if they have support for this, what could we possibly do to counteract this degradation of sea ice? It seems like more information like this should be more public, showing the tremendous harm of global warming.

  4. I saw on the discovery channel once the people that are doing these studies on the cryosphere. This job is extremely difficult; they are are usually secluded from any form of civilizations of months at a time, and they are exposed to the cold weather for long periods of time. Therefore, considering the importance of doing research about the cryosphere, private companies and the government should look into improving the conditions of the scientist to get better results in short periods of time.

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