Artic depths teeming with life

Publié le par Scorpio

Artic depths teeming with life, say explorers



By David Ljunggren



OTTAWA (Reuters) - The remotest depths of the Arctic are surprisingly full of life, including species of jellyfish and worms believed to be previously unknown, explorers who just finished exploring the area said on Friday.



The scientists, led by the University of Alaska , used robot submarines and sonar to probe an isolated 12,470-foot (3,800-meter) basin off 's Arctic coast where they fear species could be at risk from global warming.



"Unexpectedly high numbers and varieties of large Arctic jellies, squid, cod, and other animals have been found thriving in the extreme cold," the team said in a statement.



Scientists from the , , and spent 30 days on the icebreaker Healy as part of a $1 billion, 10-year global Census of Marine Life funded by governments, companies and private donors.


The Healy returned to port on Tuesday with thousands of specimens from the Chukchi and Beaufort Seas and the Canada Basin , a vast bowl walled by steep ridges and covered with ice.



"The Canada Basin is one of the world's most isolated ocean areas. Several creatures brought aboard the Healy are unfamiliar to expedition experts and may well prove new to science," said Dr. Rolf Gradinger of the University of Alaska , the chief scientist on the voyage.



The team said it found suspected new species of jellyfish and benthic bristle worms as well as the first squid, octopus and flea-like crustaceans ever seen in an icy environment.



"Overall, the densities of animals are much higher than expected," said researcher Dr. Bodil Bluhm.


The team said the data would help measure the impact of climate change and, should polar caps continue receding, the damage done by increased energy exploitation, fishing and shipping.



U.N. studies say the Arctic could be largely ice-free in summer by 2100 because of global warming, blamed mostly on gas emissions from cars, power plants and factories.



The scientists say that if the northern polar cap melts, more southerly species could enter Arctic waters and disrupt the ecology. They are due to give a news conference about the trip at 1 p.m. (1700 GMT) on Friday.


The team also said explorers would carry out similar studies in the Southern Ocean around the Antarctic, where conditions are much less settled than in the Canada Basin .



"Scientists now theorize the swirling Southern Ocean current is an evolutionary caldron, upwelling Antarctic nutrients and mixing life forms from the Pacific, Indian and Atlantic oceans, returning them in centrifuge-like fashion," the statement said.



The Australian Antarctic Division in Hobart will lead the project from December 2007 to March 2008. It will involve up to 200 scientists from 30 countries and take samples from as deep as 16,500 feet.



"Because the Southern Ocean appears to be so critical to the biology of the global ocean system, scientists are eager to understand how continued climate change, if realized, will affect it and the other oceans in turn," the team said.




Pour être informé des derniers articles, inscrivez vous :

Commenter cet article