More than 20 years after the Exxon Valdez dumped millions of litres of crude oil into Prince William Sound, the region resembles an idyllic paradise.
Killer whales ply the Alaskan waters, sea otters dive for sea urchins and puffins build their nets on windswept bluffs.
But dig a little deeper and you can still see oil welling up in puddles when scientists — and more worryingly, animals — burrow in the intertidal zone.
"That really surprised us," says environmental chemist Jeffrey Short, who helped lead studies on the after-effects of the Exxon Valdez spill for the U.S National Oceanic and Atmospheric Administration.
Short is now watching the spill in the Gulf of Mexico overtake the Exxon Valdez as the biggest spill in U.S. history.
He and other scientists says the " jury is still out" on whether it will be as big an environmental disaster.
"It's a much more complex situation," Short said in an interview from Louisiana, where he's been taking a first hand look at the spill.
With the Exxon-Valdez, he says there was a "single pulse" of oil dumped into the frigid surface waters of Prince William Sound. The corpses of thousands of marine mammals and birds soon began floating to the surface and washing ashore. "It smelled real bad," Short recalls.
In the gulf, the spill is much more complicated. Hot oil, close to 100 degree Celsius, has been pouring out of the sea floor for weeks. There has been much debate about the how much oil has escaped but a U.S. federal team reported this week that the spill appears to be far bigger than the Exxon Valdez.
While some oil has hit the shores along the gulf, Short says there is still a "huge slug" of oil offshore on the surface threatening to wash into ecologically sensitive marshes. And there is plenty more oil beneath the surface, in a kilometres-long cloud of oil micro-droplets suspended about 1,100 metres beneath the sea surface. The droplets have been created by dispersants used on the oil, and as the hot oil exits the sea floor and hits the sea water.
Short says the best-case scenario is that oil on the surface "is carried out the to sea and turns into tar balls that eventually sink to the deep sea floor." And the suspended oil micro-droplets get chewed up by microbes into harmless compounds.
"Worst case," he says, "is it all washes into coastal marshes as a sticky, gooey mass that then becomes a contact hazard for birds, marine mammals, turtles and fish."
The deathwatch has begun — NOAA reports that 212 dead and 13 live stranded turtles (of which three subsequently died in rehab) and 24 dead dolphins have been found within the "designated spill area."
There is also international concern about the impact on birds that frequent the gulf area, including millions of ducks and birds that spend time in Canada.
But it will decades before the full ecological impact is known, judging from the Exxon Valdez spill that showed the ill-effects of oil can cascade through ecosystems far longer than expected.
An estimated 42 million litres of oil spilled from the Exxon Valdez tanker in March 1989. It contaminated almost 2,000 kilometres of pristine shoreline, with some washing ashore on remote islands more than 750 kilometres from the spill.
Most of the oil could not be mopped up despite a cleanup effort that involved more than 11,000 people, $2 billion, and the most advanced technology available. It's estimated only about eight per cent was recovered at sea.
Read more: http://www.montrealgazette.com/news/Gulf+spill+stirs+memories+Exxon+Valdez+disaster/3085437/story.html#ixzz0pJuBuOVP
Killer whales ply the Alaskan waters, sea otters dive for sea urchins and puffins build their nets on windswept bluffs.
But dig a little deeper and you can still see oil welling up in puddles when scientists — and more worryingly, animals — burrow in the intertidal zone.
"That really surprised us," says environmental chemist Jeffrey Short, who helped lead studies on the after-effects of the Exxon Valdez spill for the U.S National Oceanic and Atmospheric Administration.
Short is now watching the spill in the Gulf of Mexico overtake the Exxon Valdez as the biggest spill in U.S. history.
He and other scientists says the " jury is still out" on whether it will be as big an environmental disaster.
"It's a much more complex situation," Short said in an interview from Louisiana, where he's been taking a first hand look at the spill.
With the Exxon-Valdez, he says there was a "single pulse" of oil dumped into the frigid surface waters of Prince William Sound. The corpses of thousands of marine mammals and birds soon began floating to the surface and washing ashore. "It smelled real bad," Short recalls.
In the gulf, the spill is much more complicated. Hot oil, close to 100 degree Celsius, has been pouring out of the sea floor for weeks. There has been much debate about the how much oil has escaped but a U.S. federal team reported this week that the spill appears to be far bigger than the Exxon Valdez.
While some oil has hit the shores along the gulf, Short says there is still a "huge slug" of oil offshore on the surface threatening to wash into ecologically sensitive marshes. And there is plenty more oil beneath the surface, in a kilometres-long cloud of oil micro-droplets suspended about 1,100 metres beneath the sea surface. The droplets have been created by dispersants used on the oil, and as the hot oil exits the sea floor and hits the sea water.
Short says the best-case scenario is that oil on the surface "is carried out the to sea and turns into tar balls that eventually sink to the deep sea floor." And the suspended oil micro-droplets get chewed up by microbes into harmless compounds.
"Worst case," he says, "is it all washes into coastal marshes as a sticky, gooey mass that then becomes a contact hazard for birds, marine mammals, turtles and fish."
The deathwatch has begun — NOAA reports that 212 dead and 13 live stranded turtles (of which three subsequently died in rehab) and 24 dead dolphins have been found within the "designated spill area."
There is also international concern about the impact on birds that frequent the gulf area, including millions of ducks and birds that spend time in Canada.
But it will decades before the full ecological impact is known, judging from the Exxon Valdez spill that showed the ill-effects of oil can cascade through ecosystems far longer than expected.
An estimated 42 million litres of oil spilled from the Exxon Valdez tanker in March 1989. It contaminated almost 2,000 kilometres of pristine shoreline, with some washing ashore on remote islands more than 750 kilometres from the spill.
Most of the oil could not be mopped up despite a cleanup effort that involved more than 11,000 people, $2 billion, and the most advanced technology available. It's estimated only about eight per cent was recovered at sea.
Read more: http://www.montrealgazette.com/news/Gulf+spill+stirs+memories+Exxon+Valdez+disaster/3085437/story.html#ixzz0pJuBuOVP
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