An iceberg the size of four Manhattan islands - the largest Arctic iceberg in half a century - broke away from a Greenland glacier last week. It could generate invaluable new information on climate change, scientists say.
But the massive floe could also damage oil rigs and other marine industry as it makes its way down the Newfoundland coast.
The iceberg calved off the Petermann Glacier last Thursday, and within minutes had researchers whipped into a frenzy of data collection. It has an area of 240 square kilometres and a mass of 16 gigatonnes - big enough to supply all of the United States with tap water for 120 days, according to Andreas Muenchow, a physical oceanographer at the University of Delaware.
On Tuesday, Dr. Muenchow told the U.S. congressional committee on climate change that the extremely rare event offers "exciting new ways" to explore how global warming is affecting Arctic ice. He said there is "great potential" the iceberg will fill gaps in current climate models.
Trudy Wohlleben, an ice scientist with Environment Canada, discovered the Petermann Glacier breakup early on Aug. 5. She e-mailed a researcher who works with Dr. Muenchow, and "within seconds" his research team was assembling information. "This is what makes science fun," he said, adding he had slept only five hours in the past three days.
In the next year or two the iceberg, breaking into smaller chunks along the way, will float down the Petermann Fjord, into the Nares Strait, then make its way into Baffin Bay. It will come out the Davis Strait, and move along the coast of Labrador and Newfoundland.
Newfoundland marine industries are used to dealing with ice chunks, Dr. Muenchow said, but the gigantic floe will create many more than usual.
The Canadian Ice Service will drop beacons onto the iceberg to monitor its progress.