Thursday, November 24, 2011

Must Be Another Climate Conference Looming

Amazing what sort of scientists our universities produce. Their faculties must be shared with journalism schools.  They certainly seem to be working in conjunction with one another:

Arctic sea ice in longest decline seen over past 1,450 years: study
"Research published in a top scientific journal says Arctic sea ice has declined more in the last half-century than it has any time over the last 1,450 years.

The study, which gives the most detailed picture ever of the northern oceans over the previous millennium-and-a-half, also concludes the current decline has already lasted longer than any previous one in that period.

“When we look at our reconstruction, we can see that the decline that has occurred in the last 50 years or so seems to be unprecedented for the last 1,450 years,” Christian Zdanowicz of the Geological Survey of Canada said Wednesday."
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"“It's difficult not to come up with the conclusion that greenhouse gases must have something to do with this,” added Mr. Zdanowicz, one of the co-authors of the report in Nature. [ED: Here we go again with the so-called scientists pushing correlation as proof of cause and affect.]

“We cannot account for this decline by processes that are ‘natural.’”
"Climate change is thought to be occurring faster in the Arctic than anywhere else on Earth and sea ice is considered one of the main indicators. The ice is crucial in northern ecosystems because it provides habitat for everything from plankton to polar bears.

Its gradual disappearance is also opening previously inaccessible areas to the possibility of resource development, as well as to commercial shipping.

Mr. Zdanowicz and his team combined 69 different data sources to determine the extent of sea ice for every decade going back about 1,000 years and every 25 years beyond that.

The team examined tree rings, ice cores from glaciers and lake and ocean sediments. To check the validity of their approach, scientists compared their calculations for the last couple of centuries with real-world observations from satellites, ship logs and other historical accounts.

They found that by the mid-1990s sea ice had fallen even further than in previous lows such as the so-called Medieval Warm Period between 800 and 1300.

Team members were also able to conclude that sea ice is influenced by more than just temperature. They discovered that ice actually shrank during what's known as the Little Ice Age, a period between 1450 and 1850, due to relatively warm ocean waters moving north.

That's what's happening now, said Mr. Zdanowicz.

“In the last 50 years what has really dominated the changes that we see in the Arctic Ocean is the rise in air temperatures and the rise in temperatures of the waters below.”

His study didn't look specifically at the impact of feedback loops in which open water absorbs more of the sun's heat than reflective ice. But Mr. Zdanowicz said indications are that that is starting to take effect.

“If you take this reconstruction and you put it in parallel with a number of studies that have emerged, the indications are pretty strong that the warming of the Arctic is accelerating.”

He acknowledged that although he has been able to get more detail on ice fluctuations than ever before, the time span considered in the paper isn't very long by geologic standards. [ED: Duh!!]

However, he points out he was involved with a previous paper that went back 10,000 years. [ED: And that is long by 'geologic standards????] That paper found sea ice was lower between 6,000 and 8,000 years ago — and also explained why.

“At the time, due to changes in the Earth's orbit, the northern hemisphere was receiving more solar energy than it does now,” Zdanowicz said.

“That process cannot account for what we are observing now. In fact, we should be heading into a gradual cooling trend right now if our climate was strictly controlled by orbital factors.”" [ED: Who said it is "strictly controlled by orbital factors?"]
So, 1450 years (a millennium and a half, almost) or even 10,000 years is supposed to tell us something incontrovertible about human impact on arctic sea ice. Folks. The Earth is over 4 billion years old. Throughout that time there have been many periods with no polar ice caps at all. And don't forget, only 20,000 years ago most of North America was covered with ice. Those miles-thick sheets of ice have been slowly melting and receding since then, without any help from human beings. [I wonder if he considered the impact of all those underwater super volcanoes and continental drift, two factors that aren't either "orbital factors" or the sun.]

The journalists do their bit to ramp up the scare, and make excuses.

On the other hand, who are ya gonna believe:

Large variations in Arctic sea ice
"For the last 10,000 years, summer sea ice in the Arctic Ocean has been far from constant. For several thousand years, there was much less sea ice in the Arctic Ocean – probably less than half of current amounts. This is indicated by new findings by The Centre for Geogenetics at the University of Copenhagen. The results of the study will be published in the journal Science.

Sea ice comes and goes without leaving a record. For this reason, our knowledge about its variations and extent was limited before we had satellite surveillance or observations from airplanes and ships. But now researchers at The Centre for Geogenetics at the Natural History Museum of Denmark, University of Copenhagen, have developed a method by which it is possible to measure the variations in the ice several millennia back in time.

The results are based on material gathered along the coast of northern Greenland, which scientists expect will be the final place summer ice will survive, if global temperatures continue to rise.

This means that the results from northern Greenland also indicate what the conditions are like in the ocean.

Less ice than today

Team leader Svend Funder, and two other team members and co-authors of the Science article, Eske Willerslev and Kurt Kjær, are all associated with the Danish Research Foundation at the University of Copenhagen.

Regarding the research results, Funder says:

“Our studies show that there have been large fluctuations in the amount of summer sea ice during the last 10,000 years. During the so-called Holocene Climate Optimum, from approximately 8000 to 5000 years ago, when the temperatures were somewhat warmer than today, there was significantly less sea ice in the Arctic Ocean, probably less than 50% of the summer 2007 coverage, which is absolutely lowest on record. Our studies also show that when the ice disappears in one area, it may accumulate in another. We have discovered this by comparing our results with observations from northern Canada. While the amount of sea ice decreased in northern Greenland, it increased in Canada. This is probably due to changes in the prevailing wind systems. This factor has not been sufficiently taken into account when forecasting the imminent disappearance of sea ice in the Arctic Ocean.”"
[---]
"“Our studies show that there are great natural variations in the amount of Arctic sea ice. The bad news is that there is a clear connection between temperature and the amount of sea ice. And there is no doubt that continued global warming will lead to a reduction in the amount of summer sea ice in the Arctic Ocean. The good news is that even with a reduction to less than 50% of the current amount of sea ice the ice will not reach a point of no return: a level where the ice no longer can regenerate itself even if the climate was to return to cooler temperatures. Finally, our studies show that the changes to a large degree are caused by the effect that temperature has on the prevailing wind systems. This has not been sufficiently taken into account when forecasting the imminent disappearance of the ice, as often portrayed in the media,” Funder says."
[---]
"In addition to giving us a better understanding of what the climate in northern Greenland was like thousands of years ago, it could also reveal how polar bears fared in warmer climate. The team plans to use DNA in fossil polar bear bones to study polar bear population levels during the Holocene Climate Optimum."
Settled science, my ass.

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