Wednesday, May 31, 2006

Flash: Nature Affects Global Temperature!

Looks like researchers have discovered an 'inconvenient truth' about shifting in average global temperature. An area near the North Pole had an average temperature of 74 degrees fahrenheit about 55 million years ago:

Scientists say Arctic once was tropical

Scientists have found what might have been the ideal ancient vacation hotspot with a 74-degree Fahrenheit average temperature, alligator ancestors and palm trees. It's smack in the middle of the Arctic.

First-of-its-kind core samples dug up from deep beneath the Arctic Ocean floor show that 55 million years ago an area near the North Pole was practically a subtropical paradise, three new studies show.

The scientists say their findings are a glimpse backward into a much warmer-than-thought polar region heated by run-amok greenhouse gases that came about naturally.

I'm sure it was caused by human activities... perhaps out-of-control manufacture of spears produced excessive greenhouse gases.

The writer responds to 'climate skeptics' with an irrelevancy:

Skeptics of man-made causes of global warming have nothing to rejoice over, however. The researchers say their studies appearing in Thursday's issue of Nature also offer a peak at just how bad conditions can get.

"It probably was (a tropical paradise) but the mosquitoes were probably the size of your head," said Yale geology professor Mark Pagani, a study co-author.

I don't recall global warming skeptics arguing that a warmer world would be nice. I think they are skeptical of man's role in the phenomenon. They say that temperature swings are cyclical, and that nature can produce temperature swings that swamp the contribution made by human activity. Looks like this article supports that point of view quite clearly.

Millions of years ago the Earth experienced an extended period of natural global warming. But around 55 million years ago there was a sudden supercharged spike of carbon dioxide that accelerated the greenhouse effect.

Scientists already knew this "thermal event" happened but are not sure what caused it. Perhaps massive releases of methane from the ocean, the continent-sized burning of trees, lots of volcanic eruptions.

Many experts figured that while the rest of the world got really hot, the polar regions were still comfortably cooler, maybe about 52 degrees Fahrenheit.

But the new research found the polar average was closer to 74 degrees. So instead of Boston-like weather year-round, the Arctic was more like Miami North. Way north.

"It's the first time we've looked at the Arctic, and man, it was a big surprise to us," said study co-author Kathryn Moran, an oceanographer at the University of Rhode Island. "It's a new look to how the Earth can respond to these peaks in carbon dioxide."

...What's troubling is that this hints that future projections for warming, several degrees over the next century, may be on the low end, said study lead author Appy Sluijs of the Institute of Environmental Biology at Utrecht University in the Netherlands.

Also it shows that what happened 55 million years ago was proof that too much carbon dioxide — more than four times current levels — can cause global warming, said another co-author Henk Brinkhuis at Utrecht University.

Purdue University atmospheric sciences professor Gabriel Bowen, who was not part of the team, praised the work and said it showed that "there are tipping points in our (climate) system that can throw us to these conditions."

Is there anything surprising in here? Carbon dioxide at more than 4 times the current level can lead to dramatic climate changes? I'm no scientist, but I'm guessing it's not a surprise. 'There are tipping points in our system?' You don't need to be a scientist to understand that, intuitively. Current projections for global warming may be on the low end? Based on an example of a time when CO2 concentrations were quadruple what they are today? Let's just say that that might be clearer with more explanation - but I am skeptical today.

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