Ancient ice shelf breaks free from Canadian Arctic

Chiaroscuro · Post by **Chiaroscuro** » 2006-12-29 10:09pm

From CNN news (I don't know if this goes in NP or SLM, but I guess it fits in either).

TORONTO, Ontario (AP) -- A giant ice shelf the size of 11,000 football fields has snapped free from Canada's Arctic, scientists said.

The mass of ice broke clear 16 months ago from the coast of Ellesmere Island, about 800 kilometers (497 miles) south of the North Pole, but no one was present to see it in Canada's remote north.

Scientists using satellite images later noticed that it became a newly formed ice island in just an hour and left a trail of icy boulders floating in its wake. (Watch the satellite images that clued in ice watchers)

Warwick Vincent of Laval University, who studies Arctic conditions, traveled to the newly formed ice island and could not believe what he saw.

"This is a dramatic and disturbing event. It shows that we are losing remarkable features of the Canadian North that have been in place for many thousands of years. We are crossing climate thresholds, and these may signal the onset of accelerated change ahead," Vincent said Thursday.

In 10 years of working in the region he has never seen such a dramatic loss of sea ice, he said.

The collapse was so powerful that earthquake monitors 250 kilometers (155 miles) away picked up tremors from it.

The Ayles Ice Shelf, roughly 66 square kilometers (41 square miles) in area, was one of six major ice shelves remaining in Canada's Arctic.

Scientists say it is the largest event of its kind in Canada in 30 years and point their fingers at climate change as a major contributing factor.

"It is consistent with climate change," Vincent said, adding that the remaining ice shelves are 90 percent smaller than when they were first discovered in 1906.

"We aren't able to connect all of the dots ... but unusually warm temperatures definitely played a major role."

Laurie Weir, who monitors ice conditions for the Canadian Ice Service, was poring over satellite images in 2005 when she noticed that the shelf had split and separated.

Weir notified Luke Copland, head of the new global ice lab at the University of Ottawa, who initiated an effort to find out what happened.

Using U.S. and Canadian satellite images, as well as data from seismic monitors, Copland discovered that the ice shelf collapsed in the early afternoon of August 13, 2005.

"What surprised us was how quickly it happened," Copland said. "It's pretty alarming.

"Even 10 years ago scientists assumed that when global warming changes occur that it would happen gradually so that perhaps we expected these ice shelves just to melt away quite slowly, but the big surprise is that for one they are going, but secondly that when they do go, they just go suddenly, it's all at once, in a span of an hour."

Within days, the floating ice shelf had drifted a few miles (kilometers) offshore. It traveled west for 50 kilometers (31 miles) until it finally froze into the sea ice in the early winter.

The Canadian ice shelves are packed with ancient ice that dates back over 3,000 years. They float on the sea but are connected to land.

Derek Mueller, a polar researcher with Vincent's team, said the ice shelves get weaker and weaker as the temperature rises. He visited Ellesmere's Ward Hunt Ice Shelf in 2002 and noticed it had cracked in half.

"We're losing our ice shelves, and this a feature of the landscape that is in danger of disappearing altogether from Canada," Mueller said. "In the global perspective Antarctica has many ice shelves bigger than this one, but then there is the idea that these are indicators of climate change."

The spring thaw may bring another concern as the warming temperatures could release the ice shelf from its Arctic grip. Prevailing winds could then send the ice island southwards, deep into the Beaufort Sea.

"Over the next few years this ice island could drift into populated shipping routes," Weir said. "There's significant oil and gas development in this region as well, so we'll have to keep monitoring its location over the next few years."

Better get out my global warming boots.[/quote]

Nieztchean Uber-Amoeba · Post by **Nieztchean Uber-Amoeba** » 2006-12-29 10:12pm

It's trying to escape the evil Canuckistani Liberal ThoughtPolice.

Isana Kadeb · Post by **Isana Kadeb** » 2006-12-29 11:39pm

The polar bears must have been having a real party.

Master of Cards · Post by **Master of Cards** » 2006-12-29 11:50pm

Isana Kadeb wrote:The polar bears must have been having a real party.

their getting their hawiian shirts ironed and stockpiling those little umbrellas for drinks

LMSx · Post by **LMSx** » 2006-12-30 03:10am

I'm tired of "x is the size of y football fields!" comparisons. Particularly when there's 11,000 of them. What happened to Rhode Island being a unit of measure?

While climate change is bad, it's also sort of cool that there's a giant floating island out there.

Zac Naloen · Post by **Zac Naloen** » 2006-12-30 06:47am

LMSx wrote:I'm tired of "x is the size of y football fields!" comparisons. Particularly when there's 11,000 of them. What happened to Rhode Island being a unit of measure?

While climate change is bad, it's also sort of cool that there's a giant floating island out there.

It's also not helpful when you don't know how big a bloody football field is.

Admiral Valdemar · Post by **Admiral Valdemar** » 2006-12-30 10:03am

I'm sure you've seen a football match before. That's a football field size, amazingly.

I dare anyone to say they can accurately picture 11,000 of them though. Such numbers are hard to put into context that way.

Solauren · Post by **Solauren** » 2006-12-30 10:46am

You all know it's really Canada's secret superweapon right?

We just incased it in ice to hide it from you all until it's too late!

Soon! Soon!

However, in all serious, very interesting. I wonder how the 'there's no global warming' twits will spin it

Yogi · Post by **Yogi** » 2006-12-30 12:41pm

Solauren wrote:However, in all serious, very interesting. I wonder how the 'there's no global warming' twits will spin it

The same way they always do it. "It's not because of human activity!!!"

Zac Naloen · Post by **Zac Naloen** » 2006-12-30 01:37pm

Admiral Valdemar wrote:I'm sure you've seen a football match before. That's a football field size, amazingly.

I dare anyone to say they can accurately picture 11,000 of them though. Such numbers are hard to put into context that way.

American football fields are a different size to real Football pitches

Chiaroscuro · Post by **Chiaroscuro** » 2006-12-30 02:08pm

However, in all serious, very interesting. I wonder how the 'there's no global warming' twits will spin it
The same way they always do it. "It's not because of human activity!!!"

That's what I can't understand. I mean, it's pretty obvious that global warming is because of human activity, but let's pretend for a moment that it's unclear.
Global warming is still happening. Whatever the cause, the trend is impossible to ignore, and it's going to make some pretty serious problems (in a bit of a detour, I'm really worried about hurricane season--the winter has been so incredibly warm up here in the northeast. Can you imagine what's going to happen when wind hits that warm, moisture-rich water and goes down south?).
Are they really so insecure that they can't bear to admit that any environmental problem is worth notice? If it's not our fault, it's obviously not occurring?

Chiaroscuro · Post by **Chiaroscuro** » 2006-12-30 04:29pm

PS: Osaka on a rampage! Aiee!

Sikon · Post by **Sikon** » 2006-12-30 05:16pm

Regarding those who claim global warming is not because of human activity, their motivation is often to avoid the trouble of countermeasures like reducing CO2 emissions. For example, if one incorrectly thought that the radiative forcing from CO2 and other human emissions was non-existent, with global warming having merely a natural cause like solar activity, then the counter to global warming would be just geoengineering measures like spending some money on injection of cooling dust or particulates into the upper atmosphere. In that alternate universe, measures to reduce CO2 emissions wouldn't seem as worthwhile. Of course, in reality, global warming is anthropogenic (human-caused), as discussed by others and myself in old threads here and here.

CmdrWilkens · Post by **CmdrWilkens** » 2006-12-31 12:48am

Zac Naloen wrote:
Admiral Valdemar wrote:I'm sure you've seen a football match before. That's a football field size, amazingly.

I dare anyone to say they can accurately picture 11,000 of them though. Such numbers are hard to put into context that way.
American football fields are a different size to real Football pitches

Only in girth, in length they are the same. Oh yes and 11k is waay to big a number to try and picture readily.

Srynerson · Post by **Srynerson** » 2006-12-31 02:22am

LMSx wrote:I'm tired of "x is the size of y football fields!" comparisons. Particularly when there's 11,000 of them. What happened to Rhode Island being a unit of measure?

Rhode Island isn't a particularly useful unit of measure in this context either.

An American football field, including end zones, is 57,600 square feet.

An acre is 43,560 square feet.

Rhode Island is approximately 776,957 acres or 33,844,246,920 square feet.

The ice "island" is 11,000 football fields or 633,600,000 square feet.

633,600,000/33,844,246,920 ~ 0.0187

0.0187*100 = 1.87%

I don't think it's any easier to picture 1.87% of Rhode Island than it is to picture 11,000 football fields.

Sikon · Post by **Sikon** » 2006-12-31 03:38am

Article wrote:A giant ice shelf the size of 11,000 football fields has snapped free from Canada's Arctic, scientists said.

For not just this but sometimes other topics, people often want to be able to picture a quantity. Yet what can give the most useful understanding of quantitative figures is making comparisons, not really dependent upon picturing anything.

Trying to picture quantities would just tend to be less and less practical on a larger scale anyway. For example, if one tried to picture the area of Greenland's ice sheet in terms of football fields, it would be 300,000,000 football fields. But what is more useful is a comparison that Greenland is 11% of the total area and 8% of the total volume of ice on earth.

AK-047 · Post by **AK-047** » 2006-12-31 07:34am

I don't get why people use "football fields" as a unit of measure. What ever happened to square kilometres, square miles, or the hectare? Personally I find those more useful to hear than 11,000 football fields.

Tsyroc · Post by **Tsyroc** » 2006-12-31 09:44am

Since it's a Canadian ice shelf wouldn't it be using Canadian sized football fields as the unit of measure? If so they are wider and longer than US football fields. 110yds x 65yds unless the length of the endzones is supposed to be included as well which would be another 20 yards added to each end.

"Football fields" is a really imprecise unit of measure.

Chiaroscuro · Post by **Chiaroscuro** » 2006-12-31 11:52am

But since it's CNN News, they're probably using American football fields as their standard of measure.
Man, this is getting too confusing.

Netko · Post by **Netko** » 2006-12-31 02:11pm

Not to mention that nobody has expressed the size in metric units, which would have been, y'know, the most logical ones, seeing as how they are the recognised international unit of measurement for distance and area? (Its just a little under 60 km^2 converting from Synerson's calcs).

Hmm... after doing that calc I've just noticed how retarded the original article was. A bit down they mention that the original shelf was 66km^2, so instead of mentioning a stupid, difficult to visualise statistic like 11000 football fields, they could have instead gone with the similarly impressive ~90% of a 66km^2 shelf breaking off (if a square, thats like nearly 8 kilometers to a side!). But I guess that is something even more difficult to visualise for the mathematically impaired NASCAR demographic.

(note: I'm getting a sinking feeling that my calcs are badly wrong in some way...)