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An Icy Riddle as Big as Greenland

 

Andrew C. Revkin/The New York Times

 

SWISS CAMP, Greenland Ice Cap - This vaulting heap of ice and the swirling

seas nearby have emerged as vital pieces of an urgent puzzle posed by global

warming. Can the continuing slow increase in worldwide temperatures touch

off abrupt climate upheavals? Each piece of the puzzle is a dynamic and

complicated body of water. One, the North Atlantic, is some two miles deep

and liquid. The other, this ice cap, is two miles high and solid. For scale,

think of it as a freshwater Gulf of Mexico that has been frozen, inverted

and plunked atop the world's largest island.

 

Experts have reported a series of observations in recent months that show

that the ice and the waters here are in a state of profound flux. If the

trends persist, they could mean higher sea levels and widespread coastal

flooding. There is also a small chance that the changes could lead to a

sharp cooling in parts of the Northern Hemisphere.

 

Although nobody expects shifts as rapid or cataclysmic as portrayed in the

new movie "The Day After Tomorrow," the cooling could disrupt the relatively

stable climatic conditions in which modern human societies have evolved.

 

In the last few years, Greenland's melt zone, where summer warmth turns snow

on the edge of the ice cap into slush and ponds of water, has expanded

inland, reaching elevations more than a mile high in some places, said Dr.

Konrad Steffen, a glaciologist at the University of Colorado.

 

Recent measurements by NASA scientists show that such melting can have

outsize effects on the ice sheet. Meltwater formed on the surface each

summer percolates thousands of feet down through fissures, allowing the ice

to slide more easily over the bedrock below and accelerating its slow march

to the sea.

 

Some jutting tongues of floating ice, where riverlike glaciers protrude into

the sea, are rapidly thinning. Measurements this year by Dr. Steffen and

others on the Petermann Glacier in northern Greenland show that more than

150 feet of thickness melted away under that tongue in the last year. Such

melting can speed the seaward movement of ice in the same way that removing

a doorstop lets a door swing freely.

 

As Dr. Steffen settled in with three colleagues for weeks of grueling

research at this half-buried wind-tattered camp 4,000 feet up the flanks of

the ice cap, he described how other Greenland glaciers were speeding their

discharge of icebergs into the sea.

 

"If other ice streams start to react in a similar way," he said, "then we

will actually produce much more fresh water."

 

This influx of fresh water could block North Atlantic currents that help

moderate the weather of the Northern Hemisphere. "If that feedback kicks

in," he said, "then the average person will worry."

 

Some oceanographers say global warming may already be pushing the North

Atlantic toward instability. In less than 50 years, waters deep in the North

Atlantic and Arctic have become significantly fresher, matched by growing

saltiness in the tropical Atlantic. Worldwide, seas have absorbed enormous

amounts of heat from the warming atmosphere. A big outflow of water from

Greenland could take the system to a tipping point, some say.

 

In past millenniums when such oceanic breakdowns occurred, the climate

across much of the Northern Hemisphere jumped to a starkly different state,

with deep chills and abrupt shifts in patterns of precipitation and drought

from Europe to Venezuela. Some changes persisted for centuries.

 

But whether something similar is likely to result from the new melting in

Greenland is far from clear. The forces that caused abrupt climate change in

the past, like monumental floods released from collapsing ice-age glaciers,

are different from the much slower ones being measured today.

 

Gaps in understanding are enormous. Scientists have been unable to devise

computer simulations that consistently replicate past jolts to the climate,

leaving intellectual heartburn about the future.

 

"The models are not nearly as sensitive as the real world," Dr. Richard B.

Alley, an expert at Penn State on Greenland's climate history, said. "That's

the kind of thing that makes you nervous."

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Posted

It's fun to complain about what is happening to the environment while supporting the destruction by purchasing products that do the damage.

 

I know, I know, we all drive small economy cars, not hulking SUV's? Does it really matter that you shit smaller on the sidewalk than other people? You are still shitting on the sidewalk.

 

What kind of pollution was belched into the atmosphere to make the high-tech plastics that went into your beautiful Arc'teryx pack? How about those skis?

Posted

I totally agree. The next step is getting government to heavily tax companies that produce with large amounts of pollution. We have had the technology to seriously cut down on pollution in production for years now, but there isnt much incentive to do so when you can get away with not. It doesn't help that our current government wont do a damn thing to fix the situation.

Posted

It's not the government's job to regulate everything. That's why we are where we are now. Myabe a better solution would be to only buy products from environmentally responsible companies.

 

It will be a bitch to make a waterproof breathable hemp softshell jacket, but I'm sure they will figure it out.

 

Maybe the real solution is to reduce consumption instead of asking the government to add taxes and penalties. The companies would just pass on the added cost to the consumer.

 

How do you convince a society that they eat too much of everything and that they could do without a whole lot? I haven't got a clue. I like to eat a lot of everything too.

Posted
I totally agree. The next step is getting government to heavily tax companies that produce with large amounts of pollution. We have had the technology to seriously cut down on pollution in production for years now, but there isnt much incentive to do so when you can get away with not. It doesn't help that our current government wont do a damn thing to fix the situation.

 

The next step is people putting their money where their mouth is. You don't like the way a company pollutes? Don't buy their shit. wave.gif

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