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Sun Wukong
6th May 07, 09:55 PM
Arctic melt worse than predictions



(CNN) -- Arctic sea ice is melting at a rate far quicker than predicted by climate change computer models and could disappear completely before the middle of the century, scientists have warned.


The study, published in the latest edition of the journal Geophysical Research Letters, found that the actual rate at which summer sea ice had shrunk per decade during the past 50 years was more than three times faster than an average of 18 of the most highly regarded climate simulations.


Retreating Arctic ice is considered a key indicator of the pace of global warming by environmentalists, and one that could have devastating knock-on repercussions for the wider climate, including warmer oceans and rising sea levels.


Declining ice levels also poses a threat to Arctic wildlife including polar bears, walruses and ringed seals.


According to the Intergovernmental Panel on Climate Change, which releases the third of three reports into the causes, consequences and mitigation of global warming in Thailand this week, the Arctic could be ice-free in summer by the latter part of the 21st century.


But the research, conducted by the U.S.-based National Center for Atmospheric Research (NCAR) and the University of Colorado's National Snow and Ice Data Center (NSIDC), demonstrates that the 18 models on which the IPCC has based its current recommendations could already be out of date -- and that the retreat of the ice could already be 30 years ahead of the IPCC's worst case scenario.


"This suggests that current model projections may in fact provide a conservative estimate of future Arctic change, and that the summer Arctic sea ice may disappear considerably earlier than IPCC projections," said NSIDC's Julienne Stroeve who led the study.


Climate change models of Arctic sea ice cover in September, the month when ice is usually at its minimum, suggest an average loss of 2.5 percent of ice cover per decade from 1953 to 2003. The worst case simulated by an individual model predicted a decade-on-decade reduction of 5.4 percent.


Yet when scientists studied observable data for the same period, including shipping logs, aerial photos and satellite images, they discovered the actual figure for ice loss from 1953 until 2006 to be 7.8 percent.


Furthermore, the rate of deterioration seemed to be accelerating, topping nine percent per decade since 1979.


The discrepancy between computer modelling and reality is most likely due to the fact that simulations have failed to fully take into account the impact of increased levels of carbon dioxide emissions in the atmosphere, the researchers believe.


Models have typically attributed half of the loss of ice to greenhouse gases and half to natural variations in the climate cycle. But now, many believe the first factor could be playing a significantly greater role.


Earlier this month NSICD scientists reported that winter sea ice cover in the Arctic was just 14.7 million square kilometers (5.7m square miles) -- slightly better than the all-time low 14.5m square kilometers (5.6m square miles) in 2006 -- but well short of the 15.7m average for 1979-2000.


The Arctic is especially prone to global warming because of the dangers of the so-called "feedback loop" caused by melting ice.


While ice reflects around 80 percent of the sun's heat, having a cooling effect, blue sea water can absorb up to 95 percent of solar radiation, warming up the sea and accelerating the melting process further.


"While the ice is disappearing faster than the computer models indicate, both observations and the models point in the same direction: the Arctic is losing ice at an increasingly rapid pace and the impact of greenhouse gases is growing," said co-author Marika Holland of NCAR.

Link (http://edition.cnn.com/2007/TECH/science/05/02/arctic.ice/index.html)



:pool:


Just another example of little things like FACTS being used to fuel the liberal Pro math and science agenda. It's a good thing most republicans don't believe in science, or they'd have a harder time coming to terms with being incredibly behind the learning curve. It's funny how facts are the new determinant of political allegiance.

WarPhalange
6th May 07, 09:59 PM
The clear solution is for Congress to push back Daylight Saving's Time 2 or 3 months.

Yiktin Voxbane
7th May 07, 08:56 AM
Why not tack on a healthy wage rise at the same time ...

Shawarma
7th May 07, 08:59 AM
Looks like the right time to invest in cheap real estate in the Himalayas. Will make a killing selling it as beachfront property in 2056.

Liffguard
7th May 07, 12:38 PM
Looks like the right time to invest in cheap real estate in the Himalayas. Will make a killing selling it as beachfront property in 2056.

Why would melting Arctic ice cause a rise in sea-level? Surely arctic ice is already in the ocean and therefore already displacing water? In fact, since liquid water is denser than ice, wouldn't melting sea ice cause a drop in sea-level?

Shu2jack
7th May 07, 12:45 PM
I suppose the ice above sea level would cause the oceans to rise when it melts, but I don't know by how much...

Liffguard
7th May 07, 12:57 PM
I suppose the ice above sea level would cause the oceans to rise when it melts, but I don't know by how much...

Wouldn't that be offset by the reduction in volume of the ice below sea level (since, as I said, liquid water is denser than ice)?

Shu2jack
7th May 07, 01:37 PM
Wouldn't that be offset by the reduction in volume of the ice below sea level (since, as I said, liquid water is denser than ice)?

Honestly, I don't know. I guess we will find out in the coming century.

Shawarma
7th May 07, 02:26 PM
Far as I know, it's because there's solid ground beneath a lot of the massive ice masses of the polar areas, meaning that snow that rests on rock would then flow out into the sea. Don't quote me on this.

Liffguard
7th May 07, 02:49 PM
Fair enough. I was mainly thinking of north pole sea ice. Hadn't considered northern Canada, Northern Russia, Greenland etc.

Shawarma
7th May 07, 03:15 PM
Again, I'm not sure that's true either. But rising sea levels would be quite possibly be the least dangerous thing a global increase in temperature would bring. As usual, 3rd world countries would get it straight in the ass, with droughts, massive crop failures and huge famines.

WarPhalange
7th May 07, 09:03 PM
So if we build a giant mirror and float it on the Atlantic it will eventually help cool us down?

frumpleswift
7th May 07, 09:26 PM
Just another example of little things like FACTS being used to fuel the liberal Pro math and science agenda. It's a good thing most republicans don't believe in science, or they'd have a harder time coming to terms with being incredibly behind the learning curve. It's funny how facts are the new determinant of political allegiance.

"Reality has a well known liberal bias"

Edit:

Simple experiment...fill a clear measuring cup to 2-cups. Add 5 ice cubes and observe the change in level. Remove said cubes, melt, and add the water. Observe the level again.

Voila you have proved that the water level will remain the same.

Yiktin Voxbane
7th May 07, 10:32 PM
Ok then ..... if we (as in the world) were to remove all boats from the ocean , would the sea level drop .. ?

WarPhalange
7th May 07, 11:41 PM
Not by much. Like, less than a milimeter.

Sun Wukong
8th May 07, 03:41 AM
Consequences of Global Warming
Unless we act now, our children will inherit a hotter world, dirtier air and water, more severe floods and droughts, and more wildfires
[ (http://www.nrdc.org/laondaverde/globalwarming/fcons.asp) http://www.nrdc.org/globalWarming/alaska/images/spacer.gif
ALASKA HEATS UP
Warming temperatures are already having an impact on the people, wildlife and landscape of Alaska. Click on the numbers on this map to see what's happening on the front lines of global warming. 1. Barrow (http://javascript%3Cb%3E%3C/b%3E:popwin%28%27alaska/barrow.html%27%29) 2. Shismaref (http://javascript%3Cb%3E%3C/b%3E:popwin%28%27alaska/shismaref.html%27%29) 3. Yukon River (http://javascript%3Cb%3E%3C/b%3E:popwin%28%27alaska/yukon.html%27%29) 4. Wasilla (http://javascript%3Cb%3E%3C/b%3E:popwin%28%27alaska/wasilla.html%27%29) 5. Kenai Peninsula (http://javascript%3Cb%3E%3C/b%3E:popwin%28%27alaska/kenai.html%27%29) 6. McCall Glacier (http://javascript%3Cb%3E%3C/b%3E:popwin%28%27alaska/mccall.html%27%29) 7. Fairbanks (http://javascript%3Cb%3E%3C/b%3E:popwin%28%27alaska/fairbanks.html%27%29)

The latest scientific data confirm that the earth's climate is rapidly changing. Global temperatures increased by about 1 degree Fahrenheit over the course of the last century, and will likely rise even more rapidly in coming decades. The cause? A thickening layer of carbon dioxide pollution, mostly from power plants and automobiles, that traps heat in the atmosphere.

Scientists say that unless global warming emissions are reduced, average U.S. temperatures could rise another 3 to 9 degrees by the end of the century -- with far-reaching effects. Sea levels will rise, flooding coastal areas. Heat waves will be more frequent and more intense. Droughts and wildfires will occur more often.

Disease-carrying mosquitoes will expand their range. And species will be pushed to extinction. As this page shows, many of these changes have already begun.


CLIMATE PATTERN CHANGES http://www.nrdc.org/globalWarming/images/bullet1.gifConsequence: warmer temperatures
Average temperatures will rise, as will the frequency of heat waves.
Warning signs today

Most of the United States has already warmed, in some areas by as much as 4 degrees Fahrenheit. In fact, no state in the lower 48 states experienced below average temperatures in 2002. The last three five-year periods are the three warmest on record.
Many places in North America had their hottest seasons or days on record in the late 1990s.
Since 1980, the earth has experienced 19 of its 20 hottest years on record, with 2005 and 1998 tied for the hottest and 2002 and 2003 coming in second and third.http://www.nrdc.org/globalWarming/images/bullet1.gifConsequence: drought and wildfire
Warmer temperatures could also increase the probability of drought. Greater evaporation, particularly during summer and fall, could exacerbate drought conditions and increase the risk of wildfires.
Warning signs today



The 1999-2002 national drought was one of the three most extensive droughts in the last 40 years.
In 2002, the Western United States experienced its second worst wildfire season in the last 50 years; more than 7 million acres burned. Colorado, Arizona, and Oregon had their worst seasons.
The period from April through June of 1998 was the driest three-month period in 104 years in Florida, Texas, and Louisiana.
Dry conditions produced the worst wildfires in 50 years in Florida in 1998.
April through July of 1999 was the driest four-month stretch in 105 years of record-keeping in New Jersey, Delaware, Maryland, and Rhode Island.
Montana, Colorado, and Kansas experienced severe dust storms in 2002, a product of dry conditions.
September 2001 to February 2002 was the second driest six-month period on record for the Northeast.http://www.nrdc.org/globalWarming/images/bullet1.gifConsequence: more intense rainstorms
Warmer temperatures increase the energy of the climatic system and lead to more intense rainfall at some times and in some areas.
Warning signs today

National annual precipitation has increased between 5 and 10 percent since the early 20th century, largely the result of heavy downpours in some areas.
Vermont, New Hampshire, Rhode Island, and Massachusetts each got more than double their normal monthly rainfall in June 1998.
Severe flooding in the Texas, Montana, and North Dakota during the summer of 2002 caused hundreds of millions of dollars in damage.

HEALTH EFFECTS

http://www.nrdc.org/globalWarming/images/bullet1.gifConsequence: deadly heat waves and the spread of disease
More frequent and more intensive heat waves could result in more heat-related deaths. These conditions could also aggravate local air quality problems, already afflicting more than 80 million Americans. Global warming is expected to increase the potential geographic range and virulence of tropical diseases as well.
Warning signs today

In 2003, extreme heat waves caused more than 20,000 deaths in Europe and more than 1500 deaths in India.
More than 250 people died as a result of an intense heat wave that gripped most of the eastern two-thirds of the United States in 1999.
Disease-carrying mosquitoes are spreading as climate shifts allow them to survive in formerly inhospitable areas. Mosquitoes that can carry dengue fever viruses were previously limited to elevations of 3,300 feet but recently appeared at 7,200 feet in the Andes Mountains of Colombia. Malaria has been detected in new higher-elevation areas in Indonesia.

WARMING WATER http://www.nrdc.org/globalWarming/images/bullet1.gifConsequence: more powerful and dangerous hurricanes
Warmer water in the oceans pumps more energy into tropical storms, making them more intense and potentially more destructive.
Warning signs today

The number of category 4 and 5 storms has greatly increased over the past 35 years, along with ocean temperature.http://www.nrdc.org/globalWarming/images/bullet1.gifConsequence: melting glaciers, early ice thaw
Rising global temperatures will speed the melting of glaciers and ice caps, and cause early ice thaw on rivers and lakes.
Warning signs today

At the current rate of retreat, all of the glaciers in Glacier National Park will be gone by 2070.
After existing for many millennia, the northern section of the Larsen B ice shelf in Antarctica -- a section larger than the state of Rhode Island -- collapsed between January and March 2002, disintegrating at a rate that astonished scientists. Since 1995 the ice shelf's area has shrunk by 40 percent.
According to NASA, the polar ice cap is now melting at the alarming rate of nine percent per decade. Arctic ice thickness has decreased 40 percent since the 1960s.
In 82 years of record-keeping, four of the five earliest thaws on Alaska's Tanana River were in the 1990s.http://www.nrdc.org/globalWarming/images/fcons9.gif The satellite photo at far left shows the Larson B ice shelf on Jan. 31, 2002. Ice appears as solid white. Moving to the right, in photos taken Feb. 17 and Feb. 23, the ice begins to disintegrate. In the photos at far right, taken Mar. 5 and Mar 7, note water (blue) where solid ice had been, and that a portion of the shelf is drifting away. Photos: National Aeronautics and Space Administration
http://www.nrdc.org/globalWarming/images/bullet1.gifConsequence: sea-level rise
Current rates of sea-level rise are expected to increase as a result both of thermal expansion of the oceans and of partial melting of mountain glaciers and the Antarctic and Greenland ice caps. Consequences include loss of coastal wetlands and barrier islands, and a greater risk of flooding in coastal communities. Low-lying areas, such as the coastal region along the Gulf of Mexico and estuaries like the Chesapeake Bay, are especially vulnerable.
Warning signs today

The current pace of sea-level rise is three times the historical rate and appears to be accelerating.
Global sea level has already risen by four to eight inches in the past century. Scientists' best estimate is that sea level will rise by an additional 19 inches by 2100, and perhaps by as much as 37 inches.

ECOSYSTEM DISRUPTION

Consequence: ecosystem shifts and species die-off
The increase in global temperatures is expected to disrupt ecosystems and result in loss of species diversity, as species that cannot adapt die off. The first comprehensive assessment of the extinction risk from global warming found that more than one million species could be committed to extinction by 2050 if global warming pollution is not curtailed. Some ecosystems, including alpine meadows in the Rocky Mountains, as well as tropical montane and mangrove forests, are likely to disappear because new warmer local climates or coastal sea level rise will not support them.
Warning signs today

A recent study published in the prestigious journal Nature found that at least 279 species of plants and animals are already responding to global warming. Species' geographic ranges have shifted toward the poles at an average rate of 4 miles per decade and their spring events have shifted earlier by an average of 2 days per decade.

In Washington's Olympic Mountains, sub-alpine forest has invaded higher elevation alpine meadows. In Bermuda and other places, mangrove forests are being lost.

In areas of California, shoreline sea life is shifting northward, probably in response to warmer ocean and air temperatures.

Over the past 25 years, some penguin populations have shrunk by 33 percent in parts of Antarctica, due to declines in winter sea-ice habitat.

Link:

http://www.nrdc.org/globalWarming/fcons.asp


As it is, most of this information is old, and is based on information that is more conservative than the reality of the situation. It would be food for thought, but people who chose to ignore the facts based on political allegiance apparently aren't hungry.

couch13
10th May 07, 07:30 PM
"Reality has a well known liberal bias"

Edit:

Simple experiment...fill a clear measuring cup to 2-cups. Add 5 ice cubes and observe the change in level. Remove said cubes, melt, and add the water. Observe the level again.

Voila you have proved that the water level will remain the same.

Simple experiment, fill glass with water, put ice cubes next to glass. Drop ice cubes in water and melt. Oberseve teh level.

Voila you have proved that if the ice starts on land that is above sea level (Antartica, Greenland, Northern North America) and then it melts into the sea, the sea level will rise.

frumpleswift
10th May 07, 09:17 PM
Simple experiment: Put ice in glass. Add scotch. Drink. Repeat.

I will leave the results as an exercise for the student

couch13
10th May 07, 09:26 PM
Simple experiment: Put ice in glass. Add scotch. Drink. Repeat.

I will leave the results as an exercise for the student
You can't do scotch on the rocks, that ruins the taste. Seriously, it should be a crime to water down scotch (or any liquor).

frumpleswift
10th May 07, 09:29 PM
well...a few drops of water is really the way to go...but you need to add a little H20 to bring out the full body of the scotch.

couch13
10th May 07, 09:32 PM
well...a few drops of water is really the way to go...but you need to add a little H20 to bring out the full body of the scotch.

I'll drink to that.

frumpleswift
10th May 07, 09:35 PM
spoken like a true scientist

DerAuslander108
10th May 07, 11:49 PM
You can't do scotch on the rocks, that ruins the taste. Seriously, it should be a crime to water down scotch (or any liquor).

You know nothing about drinking Scotch.

Stop assaulting my eyes with your idiocy.

couch13
10th May 07, 11:51 PM
You know nothing about drinking Scotch.

Stop assaulting my eyes with your idiocy.

Straight all the way

Kiko
11th May 07, 08:44 AM
Pour it into this
http://www.shopzoo.com/images_large/1229616.jpg

DerAuslander108
23rd May 07, 02:27 PM
Straight all the way

You don't water down Scotch. You bring out the subleties that would otherwise be over-powered.

Seriously, you know jack.

couch13
25th May 07, 11:10 PM
You don't water down Scotch. You bring out the subleties that would otherwise be over-powered.

Seriously, you know jack.

You add a bit of water to bring out the sutleties, but if you add ice or too much water, you lose the kick.

DAYoung
26th May 07, 04:45 AM
You don't water down Scotch. You bring out the subleties that would otherwise be over-powered.

Seriously, you know jack.

But ice? Seriously - wouldn't it be better to put in a few drops of water?

Kiko
26th May 07, 01:54 PM
Some like it cold.

DAYoung
26th May 07, 04:24 PM
R D R R.

frumpleswift
28th May 07, 10:01 AM
But ice? Seriously - wouldn't it be better to put in a few drops of water?

You can add as much ice as you want when it is less than 15 years old, because it is crap anyways.

DAYoung
28th May 07, 03:06 PM
You can add as much ice as you want when it is less than 15 years old, because it is crap anyways.

http://shiftingbaselines.org/blog/images/Iceberg.jpg

frumpleswift
28th May 07, 11:41 PM
And now we are back to global warming. Icebergs are about to be as fictional as good 12 year old Scotch.

Olorin
29th May 07, 01:42 AM
I guess I can come out and say it...

I always have my scotch or bourbon on the rocks.

(slinks away)

DAYoung
29th May 07, 01:54 AM
I guess I can come out and say it...

I always have my scotch or bourbon on the rocks.

(slinks away)

*crosses Olorin off Special List*