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30 years of sea ice data. The red line indicates deviation from the seasonally-adjusted mean.  (Source: Arctic Research Center, University of Illinois)
Rapid Rebound Brings Ice Back to Levels from the 1980s.

An abnormally cool Arctic is seeing dramatic changes to ice levels.  In sharp contrast to the rapid melting seen last year, the amount of global sea ice has rebounded sharply and is now growing rapidly. The total amount of ice, which set a record low value last year, grew in October at the fastest pace since record-keeping began in 1979.

The actual amount of ice area varies seasonally from about 16 to 23 million square kilometers. However, the mean anomaly-- defined as the difference between the current area and the seasonally-adjusted average-- changes much slower, and generally varies by only 2-3 million square kilometers.

That anomaly had been negative, indicating ice loss, for most of the current decade and reached a historic low in 2007. The current value is again zero, indicating an amount of ice exactly equal to the global average from 1979-2000.

Bill Chapman, a researcher with the Arctic Climate Center at the University of Illinois, says the rapid increase is "no big deal". He says that, while the Arctic has certainly been colder in recent months, the long-term decrease is still ongoing. Chapman, who predicts that sea ice will soon stop growing, sees nothing in the recent data to contradict predictions of global warming.

Others aren't quite so sure. Dr. Patrick Michaels, Professor of Environmental Science at the University of Virginia, says he sees some "very odd" things occurring in recent years. Michaels, who is also a Senior Fellow with the Cato Institute, tells DailyTech that, while the behavior of the Arctic seems to agree with climate models predictions, the Southern Hemisphere can't be explained by current theory. "The models predict a warming ocean around Antarctica, so why would we see more sea ice?" Michaels adds that large areas of the Southern Pacific are showing cooling trends, an occurrence not anticipated by any current climate model.

On average, ice covers roughly 7% of the ocean surface of the planet. Sea ice is floating and therefore doesn't affect sea level like the ice anchored on bedrock in Antarctica or Greenland. However, research has indicated that the Antarctic continent -- which is on a long-term cooling trend -- has also been gaining ice in recent years.

The primary instrument for measuring sea ice today is the AMSR-E microwave radiometer, an instrument package aboard NASA's AQUA satellite. AQUA was launched in 2002, as part of NASA's Earth Observing System (EOS).



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Atmospheric CO2
By tshaughn on 11/10/2008 12:23:26 PM , Rating: -1
As an environmental engineer, I always get people trying to pick fights with me about global warming. While I believe in it, I also think that in some cases two people with differing agendas can look at the same set of data and reach different conclusions. So, I've stopped using warming/cooling as a rationale for reducing green house gas emissions.

Instead, take a look at atmospheric CO2 levels throughout history, both first hand and from ice cores. They have been relatively steady since the last ice age at around 150 ppm, with a spike beginning not coincidentally in the late 1800s that now has us around 400 ppm. 700 ppm corresponds with being in an enclosed room with a few cigarette smokers, so when we hit 700 we will likely start seeing extinctions and problems for asthmatics, not to mention the discomfort of being in a smoke filled room all the time.

Indeed, there are many peer reviewed papers out there that call for drastic CO2 emission reductions without even mentioning warming or climate change and instead call attention to CO2 concentrations, using data that is much harder to skew.

tl;dr - We need to reduce emissions regardless of exactly what is happening with global temperatures.




RE: Atmospheric CO2
By wookie1 on 11/10/2008 4:11:57 PM , Rating: 5
"We need to reduce emissions regardless of exactly what is happening with global temperatures."

This makes no sense to me. Why should we starve plants of their food for no good reason? Pretty much all of the life on earth evolved during times where CO2 concentrations were 10X or more what they are now. CO2 != smoke, it is a colorless, odorless gas that most of the life on the planet needs to survive. Your lungs even need a little CO2 in them to function properly. Please provide supporting information that CO2 causes problems for asthmatics.


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