Giant sheets of ice measuring almost seven square miles, which is 20 square kilometres , have come adrift of the largest ice shelf in the Canadian Arctic. This is consistent with climatic warming models and as a consequence scientists warn that more could follow later this year as the summer wears on.
The ice broke away from the ice shelf on Ward Hunt Island in one of the more remote parts of northern Canada. The dislodged ice sheets have formed two floating ice islands measuring roughly 1.9 and 5.4 square miles each.
In recent decades the Arctic temperatures have risen at a greater rate than the global average which has exacerbated the problems arising in these polar regions as a result of climate change. This was the largest break of ice since the Ayles ice shelf broke away in 2005, resulting in a 25 square mile floating ice island.
The Ward Hunt shelf, measuring around 155 square miles, is one of five lying along Ellesmere island in the northern Arctic. Scientists had already identified deep fissures in the Ward Hunt shelf and as the break occurred between these two large cracks there is a fear that more could follow in the next few months before the winter freeze sets in.
At one time Ellesmere Island was home to a massive ice shelf measuring approximately 3,500 square miles. Today all that remains of that enormous ice shelf are five much smaller sheets which cover under 400 square miles in total. This is also consistent with the ever decreasing amount of sea ice to be found in the Arctic ocean.
It is believed that a strong southerly wind was the trigger for the final break off of this latest ice sheet. And as the worlds' temperatures continue to rise the ice that is there is not being reinforced during the winter months. It would likely take many years of colder temperatures to return the Arctic ice sheet to its former state, but with global temperatures continuing to rise the majority of models are predicting the possible complete disappearance of the Arctic sea ice. There are a few models which predict a possible cooling trend due to various factors including sun spot activity and the disruption of ocean currents, but these are currently in the vast minority.
Ice shelves are large platforms of thick sea ice that once floated on the surface of the oceans. This sea ice collides with the land and, combined with accumulating snow and freezing melt water, forms into a thick ice shelf over the course of thousands of years. It is only in the last 100 years or so that Ellesmere Island hasn't been completely ringed by a single massive ice shelf. It was then that the ice broke into 5 separate sheets, the largest of which was Ward Hunt.
Article Source: http://www.bharatbhasha.net
Article Url: http://www.bharatbhasha.net/environment.php/95670
Article Added on Monday, September 15, 2008
LD
| Other Articles by Mark Boardman | |
The Ice Age Cometh
There is no doubt that the world is warming up, whatever the causes. However the big question is what impact will this have on global climate? Various computer models are now predicting a new ice age. Caused by global warming? An oxymoron surely? Well maybe not.
This winter (2007-2008) snow fall and snow cover has been at its greatest over North America, Siberia and China since 1966. And the Arctic ice sheet, which for so long has been all but doomed by modern climate models, has had a...
|
| |
