'Unprecedented' warming drives dramatic ecosystem shifts in North Atlantic
A Cornell study reports that as a result of this warming, which has caused Arctic freshwater ice to melt and flow southward, the ranges of some cold-water, northern marine species have been moving down the North American coast -- a counterintuitive finding.
The paleo-climate record shows very rapid periods of cooling in the past, when temperatures have dropped by as much as 18 degrees Fahrenheit (10 degrees Celsius) in a matter of years to decades, but "the rate of warming we are seeing [now] is unprecedented in human history," said Cornell oceanographer Charles Greene, the lead author of the study, published in the November issue of the journal Ecology (Vol. 89, No. 11).
During the past 50 years, melting Arctic ice sheets and glaciers have periodically released cold, low-salt water from the Arctic Ocean into the Arctic Ocean. This has led to dramatic ecosystem shifts as far south as North Carolina and extensive geographic range shifts of many plant and animal species, he said. One microscopic algal species from the Pacific Ocean, not seen in the North Atlantic for over 800,000 years, has reinvaded the North Atlantic from the Arctic Ocean during the past decade.
The paleo-climate record shows very rapid periods of cooling in the past, when temperatures have dropped by as much as 18 degrees Fahrenheit (10 degrees Celsius) in a matter of years to decades, but "the rate of warming we are seeing [now] is unprecedented in human history," said Cornell oceanographer Charles Greene, the lead author of the study, published in the November issue of the journal Ecology (Vol. 89, No. 11).
During the past 50 years, melting Arctic ice sheets and glaciers have periodically released cold, low-salt water from the Arctic Ocean into the Arctic Ocean. This has led to dramatic ecosystem shifts as far south as North Carolina and extensive geographic range shifts of many plant and animal species, he said. One microscopic algal species from the Pacific Ocean, not seen in the North Atlantic for over 800,000 years, has reinvaded the North Atlantic from the Arctic Ocean during the past decade.