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Glacier Bay National Park. Two and a half centuries ago, the entire area was covered by thick sheets of ice.
High snowfall and cold weather to blame.

A bitterly cold Alaskan summer has had surprising results. For the first time in the area's recorded history, area glaciers have begun to expand, rather than shrink. Summer temperatures, which were some 3 degrees below average, allowed record levels of winter snow to remain much longer, leading to the increase in glacial mass.

"In mid-June, I was surprised to see snow still at sea level in Prince William Sound", said glaciologist Bruce Molnia. "In general, the weather this summer was the worst I have seen in at least 20 years".

"On the Juneau Icefield, there was still 20 feet of new snow on the surface [in] late July. At Bering Glacier, a landslide I am studying [did] not become snow free until early August."

Molnia, who works for the US Geological Survey, said it's been a "long time" since area glaciers have seen a positive mass balance -- an increase in the total amount of ice they contain.

Since 1946, the USGS has maintained a research project measuring the state of Alaskan glaciers. This year saw records broken for most snow buildup. It was also the first time since any records began being that the glaciers did not shrink during the summer months.

Those records date from the mid 1700s, when the region was first visited by Russian explorers.  Molnia estimates that Alaskan glaciers have lost about 15% of their total area since that time -- an area the size of Connecticut.

One of the largest areas of shrinkage has been at the national park of Glacier Bay. When Alexei Ilich Chirikof first arrived in 1741, the bay didn't exist at all -- only a solid wall of ice. From that time until the early 1900s, the ice retreated some 50 miles, to form the bay and surrounding area.

Accordingly to Molnia, a difference of just 3 or 4 degrees is enough to shift the mass balance of glaciers from rapid shrinkage to rapid growth. From the 1600s to the 1900s, that’s just the amount of warming that was seen, as the planet exited the Little Ice Age.

Molnia says one cold summer doesn't mean the start of a new climatic trend. At least years like this, however, might mark the beginning of another Little Ice Age.

As DailyTech reported earlier, Arctic sea ice this year has also increased substantially from its low in 2007.



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RE: Son of a...
By Lifted on 10/16/2008 10:28:39 AM , Rating: 2
What would happen if all of the ice covering Antarctica melted? Would most of the planet be covered by water, or just coastal areas?

If yes...

Could a brief warming of Earth and melting of the poles have caused the sudden extinction of most dinosaurs and plant life (on land), yet happened so briefly as to leave little evidence that most of the earth was covered in water at one or more points in history?


RE: Son of a...
By Lifted on 10/16/08, Rating: 0
RE: Son of a...
By Lifted on 10/16/08, Rating: 0
RE: Son of a...
By borismkv on 10/16/2008 11:12:23 AM , Rating: 4
<Insert Noah's ark joke here>


RE: Son of a...
By masher2 (blog) on 10/16/2008 11:10:44 AM , Rating: 4
If all the ice in Antarctica and Greenland melted, it would raise sea levels by about 70 meters...so any area more than 70m above sea level would not be submerged. Ice mass in Antarctica is on a long-term growing trend, however, so that's a very unlikely event anytime in the next several thousand years.

There have been times in Earth's far past when sea levels were as much as 400m higher than they are today...but that seems to have been driven by changes in topology as well as melting ice -- a 'flatter' Earth can be covered by a much smaller amount of water.


RE: Son of a...
By phazers on 10/16/2008 3:25:44 PM , Rating: 2
I read only 60 meters (200 ft) - see the Wiki article http://en.wikipedia.org/wiki/Antarctica - but still that would put most of Florida under water, not to mention the Netherlands.

Conversely if most of the Artic icecap melted, sea levels would not change much since Artic ice is mostly floating already. If you have a glass full of ice cubes and water, and leave it overnight, you won't find a big puddle next morning (other than condensation). In fact, ice is less dense than water (since it floats), so the total volume would go down as the ice melts.

If Al Gore melted, we'd all be knee-deep in liquid fertilizer :)


RE: Son of a...
By FITCamaro on 10/16/2008 3:31:53 PM , Rating: 1
If Al Gore dies ManBearPig will kill our imaginations. The solution is to nuke our imaginations.


RE: Son of a...
By modus2 on 10/17/2008 12:48:01 PM , Rating: 2
Actually the volume remains constant, the ice displaces exactly the same amount of water it contains -- http://en.wikipedia.org/wiki/Arcimedes#The_Golden_...

There is one reservation though, since desity varies with temperature (highest at 4C (approx 40F)) the above holds if the water in the glass is given sufficient time to reach the same temperature after ice insertion as it had before.


RE: Son of a...
By jimbojimbo on 10/16/2008 2:22:06 PM , Rating: 2
A lot of people think if you put ice in a glass and fill it to the very top with water that when the ice melts the water will rise and spill all over the place.


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