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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 masher2 (blog) on 11/9/2008 6:45:54 PM , Rating: 5
> "All they said was - "We do not have a good quantitative understanding of our climate machine"

They said a great deal more than that. From Science Magazine, Mar 1, 1975:
quote:
According to the Academy [the NAS] report on climate, we may be approaching the the end of a major interglacial cycle, with the approach of a full-blown 100-year long ice age a real possibility...with ice packs building up relatively quickly from local snowfall that fails to melt form winter to winter"
Many books and research papers were also published on the topic. Nigel Calder, then-editor of New Scientist, wrote, "the threat of a new Ice Age must now stand alongside nuclear war as a lifely source of wholesale death and misery for mankind". Scientist Lowell Ponte wrote The Cooling, which said that global cooling was *already* causing famine in major parts of the world.

In fact, the esteemed Hadley Center, today one of the shrillest voices in support of AGW, was originally founded to study global cooling, not warming. Scientist Reid Bryson-- the most cited research meteorologist in the world-- blamed the rapid cooling on "increased air pollution".

The media was awash with stories on global cooling. National Geographic run a full series, Newsweek said,
quote:
"there are ominous signs that the earth's weather patterns have begun to change dramatically and that these changes portend a drastic decline in food production -- with serious political implications for just about every nation on earth

Time Magazine's "Another Ice Age" story was on the cover of the June edition in 1974. It was full of quotes from scientists, and left little room for doubt.


RE: Pace vs. Quantity
By mmcdonalataocdotgov on 11/10/2008 8:51:59 AM , Rating: 4
Given the actual data, as near we can can get it (remember, our ability to provide data is constantly improving, but we have only been keeping this sort of data since 1979, as the article points out) we are still just approaching the planetary temperature that we had in the year 1700. Since then the temperature went way down, and we are just nearing the 1700 mark again, according to our best data.

Also note that Venus, the Earth, Mars and Jupiter are all showing increased temperatures to the same degree, so the cause is not certain.

No need to engage in ad hominem arguments if you want to discuss science. And please don't reason from your conclusions. That is also a logical fallacy (rational consctructionism - e.g. creationism, and arguing science based on political conclusions.) Are either of you a scientist anyway?


RE: Pace vs. Quantity
By dever on 11/10/2008 2:43:00 PM , Rating: 1
First you criticize for using ad hominem arguments, then suggest using the fallacy of appealing to authority instead?


RE: Pace vs. Quantity
By OoklaTheMok on 11/10/2008 10:04:55 AM , Rating: 2
But I think we need to remind ourselves that the projected "cooling period" from the 70's was due to atmospheric particulates, largely from coal plants without any form of emission controls. The particulates increased the reflective properties of our atmosphere, which in turn resulted in lower temperatures and the projected "cooling period". Now we find ourselves in a warming period, and again pollution is the culprit. I find it ignorant to question if human actions could possibly have an effect on our ecosystem, because it has already been shown that we can and have had such an impact.


RE: Pace vs. Quantity
By hlper on 11/10/2008 1:45:52 PM , Rating: 2
I agree that polution and global warming are threats. However, this is why Mr. Asher's posts are so important to a complete diologue.

In both cases you said that polution was the cause. However, the truth is that although there may be scientific evidence to support these points of view, neither case can be completly validated. These conclusions are from models, and it is impossible to demonstrate in an actual system that removal of these polutants would change anything. We would need another Earth for that.

At any rate, can it be a bad idea to control the rate at which we change the composition of our atmosphere? I vote no.


RE: Pace vs. Quantity
By foolsgambit11 on 11/10/2008 3:35:36 PM , Rating: 2
You act as if these two scientific concepts couldn't possibly both be right. Now, I'm not saying they are both right, but here's a narrative that fits both ideas:

The planet was naturally cooling (as the NAS report on climate suggested), but as human-released greenhouse gases began to build up in the atmosphere, these vectors have actually created overall warming. Since the natural baseline for climate would be a cooler planet, the effects of human activity would actually be greater than represented from the data alone.

Of course, I'm not suggesting this is what's actually going on, only that there is an explanation that allows both statements to be true.

But when you took that narrative and applied it to this story, it would indicate that our baseline average for Arctic ice cap size, based on data from the 70's to 2000, would be, historically speaking, high, and that at this point we are actually above the trend line for a longer-term average. Unfortunately, we don't have accurate regular data for all of the Arctic every year before the satellite age.


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