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Showing posts from December 25, 2012

Earth's Inconstant Magnetic Field

Our planet's magnetic field is in a constant state of change, say researchers who are beginning to understand how it behaves and why.





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December 29, 2003: Every few years, scientist Larry Newitt of the Geological Survey of Canada goes hunting. He grabs his gloves, parka, a fancy compass, hops on a plane and flies out over the Canadian arctic. Not much stirs among the scattered islands and sea ice, but Newitt's prey is there--always moving, shifting, elusive.

His quarry is Earth's north magnetic pole.

At the moment it's located in northern Canada, about 600 km from the nearest town: Resolute Bay, population 300, where a popular T-shirt reads "Resolute Bay isn't the end of the world, but you can see it from here." Newitt stops there for snacks and supplies--and refuge when the weather gets bad. "Which is often," he says.

Right: The movement of Earth's north magnetic pole acr…

Forget global warming, Alaska is headed for an ice age

Alaska is going rogue on climate change.

Defiant as ever, the state that gave rise to Sarah Palin is bucking the mainstream yet again: While global temperatures surge hotter and the ice-cap crumbles, the nation's icebox is getting even icier.

That may not be news to Alaskans coping with another round of 50-below during the coldest winter in two decades, or to the mariners locked out of the Bering Sea this spring by record ice growth.

Then again, it might. The 49th state has long been labeled one of the fastest-warming spots on the planet. But that's so 20th Century.

In the first decade since 2000, the 49th state cooled 2.4 degrees Fahrenheit.
Widespread warming

That's a "large value for a decade," the Alaska Climate Research Centerat the University of Alaska Fairbanks said in "The First Decade of the New Century: A Cooling Trend for Most of Alaska."

The cooling is widespread -- holding true for 19 of the 20 National Weather Service stations sprinkled fro…

EARTH'S SHRINKING ATMOSPHERE BAFFLES SCIENTISTS

An increase in CO2 could be one reason why a layer of Earth's upper atmosphere went through its biggest contraction in 43 years.
THE GIST ·Earth's thermosphere went through its biggest contraction in 43 years. ·Researchers expected to see a contraction due to a solar minimum, but not this significant. ·One explanation may be an increase in carbon dioxide in the atmosphere. enlarge More than half of the upper atmosphere's shrinkage cannot be explained. Click to enlarge this image. 
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