Science > Abortion > Natural weather variations responsible for 2007 Arctic ice decline -Experts
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Science > Abortion |
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03 Jan 2008 07:14:04 AM |
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Natural weather variations responsible for 2007 Arctic ice decline -Experts |
Shifting heat layers above Arctic to blame for ice crisis: study
18 hours ago
PARIS (AFP) -- The dramatic loss of the Arctic ice cap may have been
triggered by disruption to the thermal layers of atmosphere stacked
over Earth's far north, according to Swedish research to be published
Thursday.
The study, published in Nature, offers a new explanation for the rise
in the Arctic's surface temperature, which over the past century has
been nearly two degrees Celsius (3.6 Fahrenheit), or twice the global
average.
Until now, the big suspect in "Arctic amplification" has been
reflectivity of sunlight.
When the Sun's rays hit snow or ice, most of that solar energy bounces
back into space -- but as those melting surfaces give way to dark-blue
sea, the heat is absorbed instead.
This self-reinforcing process, called a feedback, is an established
factor in accelerating warming in snow and ice.
But Stockholm University scientists led by Rune Graversen believe a
possibly bigger cause for Arctic warming could be changes in heat
transport in the middle of the troposphere, an atmospheric band that
extends 10 kilometers (seven miles) above Earth's surface.
In polar regions, the layers of relative heat above the surface are
usually stable. But Graversen says that over the last two decades or
so there have been changes in Arctic atmospheric circulation which
have brought in heat and moisture.
The moisture is particularly important, as it helps form persistent
low cloud over the Arctic.
Moisture-laden clouds at this altitude tend to absorb heat from the
Sun, thus bringing a warming effect close to the surface. In contrast,
high-altitude clouds, which mainly comprise icy crystals, reflect heat
back into space, and thus cool the surface.
The circulatory shifts have an especially big impact in summer, says
Graversen.
In 2007, summer sea ice in the Arctic shrank to about four million
square kilometers (2.4 million square miles), a 23 percent decrease
from the previous record low of 5.3 million square kilometers in 2005.
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| User: "Ouroboros_Rex" |
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| Title: Re: Natural weather variations responsible for 2007 Arctic ice decline - Experts |
03 Jan 2008 09:39:35 AM |
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Another liar. The article says 'may', and 'natural' is never mentioned.
lol
<d.086@hotmail.com> wrote in message
news:077bcce6-ae50-471c-afa9-41e05692c36c@t1g2000pra.googlegroups.com...
In polar regions, the layers of relative heat above the surface are
usually stable. But Graversen says that over the last two decades or
so there have been changes in Arctic atmospheric circulation which
have brought in heat and moisture.
Last two decades, eh? Wonder why?
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| User: "Tunderbar" |
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| Title: Re: Natural weather variations responsible for 2007 Arctic icedecline - Experts |
03 Jan 2008 08:37:31 AM |
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On Jan 3, 7:14=A0am, wrote:
Shifting heat layers above Arctic to blame for ice crisis: study
18 hours ago
PARIS (AFP) -- The dramatic loss of the Arctic ice cap may have been
triggered by disruption to the thermal layers of atmosphere stacked
over Earth's far north, according to Swedish research to be published
Thursday.
The study, published in Nature, offers a new explanation for the rise
in the Arctic's surface temperature, which over the past century has
been nearly two degrees Celsius (3.6 Fahrenheit), or twice the global
average.
Until now, the big suspect in "Arctic amplification" has been
reflectivity of sunlight.
When the Sun's rays hit snow or ice, most of that solar energy bounces
back into space -- but as those melting surfaces give way to dark-blue
sea, the heat is absorbed instead.
This self-reinforcing process, called a feedback, is an established
factor in accelerating warming in snow and ice.
But Stockholm University scientists led by Rune Graversen believe a
possibly bigger cause for Arctic warming could be changes in heat
transport in the middle of the troposphere, an atmospheric band that
extends 10 kilometers (seven miles) above Earth's surface.
In polar regions, the layers of relative heat above the surface are
usually stable. But Graversen says that over the last two decades or
so there have been changes in Arctic atmospheric circulation which
have brought in heat and moisture.
The moisture is particularly important, as it helps form persistent
low cloud over the Arctic.
Moisture-laden clouds at this altitude tend to absorb heat from the
Sun, thus bringing a warming effect close to the surface. In contrast,
high-altitude clouds, which mainly comprise icy crystals, reflect heat
back into space, and thus cool the surface.
The circulatory shifts have an especially big impact in summer, says
Graversen.
In 2007, summer sea ice in the Arctic shrank to about four million
square kilometers (2.4 million square miles), a 23 percent decrease
from the previous record low of 5.3 million square kilometers in 2005.
Hey, I thought there was a consensus on all things climate related.
Instead of scientists speculating, why don't they just asked the
climate modellers and activists at the IPCC, they already know
everything.
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| User: "Lloyd" |
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| Title: Re: Natural weather variations responsible for 2007 Arctic icedecline - Experts |
03 Jan 2008 09:45:16 AM |
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On Jan 3, 8:14 am, wrote:
Shifting heat layers above Arctic to blame for ice crisis: study
18 hours ago
PARIS (AFP) -- The dramatic loss of the Arctic ice cap may have been
triggered by disruption to the thermal layers of atmosphere stacked
over Earth's far north, according to Swedish research to be published
Thursday.
The study, published in Nature, offers a new explanation for the rise
in the Arctic's surface temperature, which over the past century has
been nearly two degrees Celsius (3.6 Fahrenheit), or twice the global
average.
Until now, the big suspect in "Arctic amplification" has been
reflectivity of sunlight.
When the Sun's rays hit snow or ice, most of that solar energy bounces
back into space -- but as those melting surfaces give way to dark-blue
sea, the heat is absorbed instead.
This self-reinforcing process, called a feedback, is an established
factor in accelerating warming in snow and ice.
But Stockholm University scientists led by Rune Graversen believe a
possibly bigger cause for Arctic warming could be changes in heat
transport in the middle of the troposphere, an atmospheric band that
extends 10 kilometers (seven miles) above Earth's surface.
In polar regions, the layers of relative heat above the surface are
usually stable. But Graversen says that over the last two decades or
so there have been changes in Arctic atmospheric circulation which
have brought in heat and moisture.
The moisture is particularly important, as it helps form persistent
low cloud over the Arctic.
Moisture-laden clouds at this altitude tend to absorb heat from the
Sun, thus bringing a warming effect close to the surface. In contrast,
high-altitude clouds, which mainly comprise icy crystals, reflect heat
back into space, and thus cool the surface.
The circulatory shifts have an especially big impact in summer, says
Graversen.
In 2007, summer sea ice in the Arctic shrank to about four million
square kilometers (2.4 million square miles), a 23 percent decrease
from the previous record low of 5.3 million square kilometers in 2005.
Wrong. Here's what the article actually says:
"New research points a finger at a natural and cyclical increase in
the amount of energy in the atmosphere that moves from south to north
around the Arctic Circle.
But that energy transfer, which comes with storms that head north
because of ocean currents, is not acting alone either, scientists say.
Another upcoming study concludes that the combination of both that
natural energy transfer increase and man-made global warming serve as
a one-two punch that is pushing the Arctic over the edge.
Rune Graversen, the Nature study co-author and a meteorology
researcher at Stockholm University in Sweden, said a shift in energy
transfer explains the thawing more, including what's happening in the
atmosphere, but does not contradict consensus global warming science.
Oceanographer James Overland, who reviewed Graversen's study for
Nature, said the research dovetails with an upcoming article of his
which concludes that the Arctic thawing is a combination of the two.
"If we didn't have the little extra kick from global warming then we
wouldn't have gone past the threshold for the change in sea ice," said
Overland, of the National Oceanic and Atmospheric Administration's lab
in Seattle.
Other researchers said Graversen's study underestimates the effect of
global warming because it relied on older data that stopped at 2001
and wasn't the most accurate."
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| User: "Ouroboros_Rex" |
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| Title: Re: Natural weather variations responsible for 2007 Arctic ice decline - Experts |
03 Jan 2008 11:40:39 AM |
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"Lloyd" <lparker@emory.edu> wrote in message
news:bd6d7f38-69a7-4fd8-b86d-552529187e70@n20g2000hsh.googlegroups.com...
On Jan 3, 8:14 am, wrote:
Shifting heat layers above Arctic to blame for ice crisis: study
18 hours ago
PARIS (AFP) -- The dramatic loss of the Arctic ice cap may have been
triggered by disruption to the thermal layers of atmosphere stacked
over Earth's far north, according to Swedish research to be published
Thursday.
The study, published in Nature, offers a new explanation for the rise
in the Arctic's surface temperature, which over the past century has
been nearly two degrees Celsius (3.6 Fahrenheit), or twice the global
average.
Until now, the big suspect in "Arctic amplification" has been
reflectivity of sunlight.
When the Sun's rays hit snow or ice, most of that solar energy bounces
back into space -- but as those melting surfaces give way to dark-blue
sea, the heat is absorbed instead.
This self-reinforcing process, called a feedback, is an established
factor in accelerating warming in snow and ice.
But Stockholm University scientists led by Rune Graversen believe a
possibly bigger cause for Arctic warming could be changes in heat
transport in the middle of the troposphere, an atmospheric band that
extends 10 kilometers (seven miles) above Earth's surface.
In polar regions, the layers of relative heat above the surface are
usually stable. But Graversen says that over the last two decades or
so there have been changes in Arctic atmospheric circulation which
have brought in heat and moisture.
The moisture is particularly important, as it helps form persistent
low cloud over the Arctic.
Moisture-laden clouds at this altitude tend to absorb heat from the
Sun, thus bringing a warming effect close to the surface. In contrast,
high-altitude clouds, which mainly comprise icy crystals, reflect heat
back into space, and thus cool the surface.
The circulatory shifts have an especially big impact in summer, says
Graversen.
In 2007, summer sea ice in the Arctic shrank to about four million
square kilometers (2.4 million square miles), a 23 percent decrease
from the previous record low of 5.3 million square kilometers in 2005.
Wrong. Here's what the article actually says:
"New research points a finger at a natural and cyclical increase in
the amount of energy in the atmosphere that moves from south to north
around the Arctic Circle.
But that energy transfer, which comes with storms that head north
because of ocean currents, is not acting alone either, scientists say.
Another upcoming study concludes that the combination of both that
natural energy transfer increase and man-made global warming serve as
a one-two punch that is pushing the Arctic over the edge.
Rune Graversen, the Nature study co-author and a meteorology
researcher at Stockholm University in Sweden, said a shift in energy
transfer explains the thawing more, including what's happening in the
atmosphere, but does not contradict consensus global warming science.
Oceanographer James Overland, who reviewed Graversen's study for
Nature, said the research dovetails with an upcoming article of his
which concludes that the Arctic thawing is a combination of the two.
"If we didn't have the little extra kick from global warming then we
wouldn't have gone past the threshold for the change in sea ice," said
Overland, of the National Oceanic and Atmospheric Administration's lab
in Seattle.
Other researchers said Graversen's study underestimates the effect of
global warming because it relied on older data that stopped at 2001
and wasn't the most accurate."
Ah, no wonder he left off the link. lol
How come all denialists lie?
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