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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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RE: Pace vs. Quantity
By lucasb on 11/8/2008 2:42:23 PM , Rating: 1
quote:
Antarctica doesn't agree with model predictions.

Why should it have to agree with models? The Antartic continent is a special beast, as demostrated by the uniqueness of the ozone depletion dynamics. Models are imperfect and are being refined periodically. Expecting the Antartic climate to adjust flawlessly to models is naive at best.
There are countless explanations for the milder warming (or even mild cooling) of the climate and the (disputed)* growth of the ice sheet:
- The circumpolar current acting as a sort of "buffer" preventing the arriving of warmer water from the tropics.
- It seems logical to observe a milder change in the south, where sea (a moderating fore in weather) is much more abundant than land (I live in Argentina so I know what I'm talking about)
- A warmer climate means more precipitation (rain or snow). So, if temperatures go from -30 ºC to -15 ºC, you're still well below the freezing point (no ice melting expected) but you may expect more snowfall and rainfall which can become new ice.
- The reduction in ozone, which is a greenhouse gas in itself.
*http://www.jpl.nasa.gov/news/news.cfm?release=2008...

Still, some people believe than mankind doesn't have the means to transform the environment on a worldwide scale.

quote:
The term Anthropocene, proposed and increasingly employed to denote the current interval of anthropogenic global environmental change, may be discussed on stratigraphic grounds. A case can be made for its consideration as a formal epoch in that, since the start of the Industrial Revolution, Earth has endured changes sufficient to leave a global stratigraphic signature distinct from that of the Holocene or of previous Pleistocene interglacial phases, encompassing novel biotic, sedimentary, and geochemical change. These changes, although likely only in their initial phases, are sufficiently distinct and robustly established for suggestions of a Holocene–Anthropocene boundary in the recent historical past to be geologically reasonable. The boundary may be defined either via Global Stratigraphic Section and Point (“golden spike”) locations or by adopting a numerical date. Formal adoption of this term in the near future will largely depend on its utility, particularly to earth scientists working on late Holocene successions

http://www.gsajournals.org/perlserv/?request=get-a...


RE: Pace vs. Quantity
By teldar on 11/8/2008 6:00:05 PM , Rating: 5
So....
You want to completely throw out predictions which said that Antarctica was warming and accept all the portions of them that say the entire earth is warming?

I would think this is an all or nothing scenario.... Either the predictions are right or they are not.
I don't think you can just take out an entire continent's predictions. otherwise you'd have to throw out all the other continent's predictions as well....
There was a comment earlier about 'cherry picking' and I believe this conforms to that comment.

T


RE: Pace vs. Quantity
By lucasb on 11/8/2008 9:36:36 PM , Rating: 3
quote:
I would think this is an all or nothing scenario.... Either the predictions are right or they are not.

Amazing. Everything has to be black or white, right or left, with us or against us. What a wonderful mindset.
quote:
You want to completely throw out predictions which said that Antarctica was warming and accept all the portions of them that say the entire earth is warming?

quote:
There was a comment earlier about 'cherry picking' and I believe this conforms to that comment.

Interesting. I say that inconsistencies between the models and the dynamics of the Antartic climate aren't that surprising. I even recognize that this is a weak point in the theoretical framework of climate change. Yet you talk about 'cherry picking' evidence, when that's the behaviour commonly associated with climate change deniers (note that I'm saying deniers not skeptics).
Why not talk about the Antarctic Peninsula?
http://www.antarctica.ac.uk//bas_research/our_rese...
http://svs.gsfc.nasa.gov/vis/a000000/a003100/a0031...
http://www.sciencedaily.com/releases/2008/06/08061...
Why not talk about the correct predictions and general achievements of the climate change theory?
http://www.nature.com/nature/journal/v421/n6918/ab...
http://www.grida.no/climate/ipcc_tar/wg1/figspm-4....
http://www.aip.org/history/climate/GCM.htm
http://www.nature.com/ngeo/journal/v1/n11/abs/ngeo...
http://www.nature.com/climate/2008/0811/full/clima...
http://www.livescience.com/environment/070716_gw_n...
http://news.bbc.co.uk/1/hi/uk/163423.stm
http://scholar.google.com.ar/scholar?hl=es&lr=&q=p...


RE: Pace vs. Quantity
By Suntan on 11/10/2008 1:23:54 PM , Rating: 4
quote:
Amazing. Everything has to be black or white, right or left, with us or against us. What a wonderful mindset.


Ahh, yeah. That's called the scientific method. Your theory is either right or it is wrong. Shades of grey are a concept left for political and social topics. Not science.

I could see it being argued back then, "Ok, Ok. So the *whole* world is not flat. Surely vast portions of it still are! People, people come on, most of the world is still flat. yes, if you go in that direction you will be ok, but if you go over in that direction, surely you will fall off the edge!"

-Suntan


RE: Pace vs. Quantity
By foolsgambit11 on 11/10/2008 4:02:41 PM , Rating: 2
Well, not quite. The terms 'right' and 'wrong' don't really perfectly apply to the scientific method. Your model either agrees with or does not agree with current data, given a certain margin of error. It either explains or does not explain phenomena. It predicts the results of further experimentation or it is refuted by further experimentation. But it's not black and white.

Newton was 'right' for three hundred years. Einstein's special and general theories of relativity still aren't 'right' in the strictest sense - they can't explain quantum phenomena. Evolution is not seen the same way Darwin pictured it exactly, but that doesn't make him 'wrong', per se. (Although so far, evolution has been mostly an explanative theory, not so much predictive, outside of microevolutionary lab experiments.)

Quantum mechanics is a great example of an evolving theory, which has gotten better and better as more and more precise and varied data points were made available. It also has enormous predictive powers.

Unfortunately, climate theories still are in their infancy. No one would deny that modeling is evolving, and most would agree that it will never be perfect - there are just too many interacting variables. But there is good reason to believe we could get it 'close enough', like Newton's theory of universal gravitation was 'close enough' for hundreds of years, and had enormous predictive powers.

I think anybody with an open mind would acknowledge that it is possible for human pollution to do enormous damage to the environment (by which I mean make it a poor environment for humans, specifically). The exact risk is uncertain, but the risk of damage should be enough to compel us to make massive investments in improving the 'greenness' of our technology. After all, the threat of attack from foreign governments and non-state actors is enough for us to spend billions every year on our military and military technology.


RE: Pace vs. Quantity
By lucasb on 11/10/08, Rating: 0
RE: Pace vs. Quantity
By wookie1 on 11/10/2008 2:40:19 PM , Rating: 5
I encourage anyone interested to go to www.climateaudit.org, where they attempt to reproduce the work submitted to the journals, and especially www.rankexploits.com/musings, where they apply statistical tests of actual temperature data vs. the model predictions to determine their skill. Right now, the climate models have been falsified with 95% confidence interval.


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