AP Photo/Petar Petrov
If we judged the worst oil spills in history only by gallons leaked, the Exxon Valdez disaster -- which occurred 25 years ago today -- would not make the list. However, adding in environmental impacts and clean-up efforts, it's still recognized as one of most damaging spills to date. In 2009, Exxon Mobil Corp. was ordered to pay about $500 million in interest on punitive damages for the oil spill off Alaska, nearly doubling the payout to Alaska Natives, fishermen, business owners and others harmed by the 1989 disaster. Debate continues over what qualifies as an oil "disaster," but here are 10 that would certainly make the list.BLOG: Sea Otters Finally Rebound From Exxon Valdez
NOAA, USGS, Getty Images
As the largest oil spill disaster in U.S. history, the
incident continues to leave an incredibly damaging black mark. Shortly after midnight on March 24, 1989, the tanker was traveling outside of normal shipping lanes to avoid ice, when it struck the Blight Reef in Prince William Sound, Alaska. Out of the 53 million gallons of crude oil onboard, 11 million gallons were lost in the accident. The size of the spill and its remote location in the pristine Alaskan wilderness made clean-up a horrendous task. Ten million birds, whales, otters and other animals were placed immediately at risk and thousands died.VIDEO: Gulf Oil Spill Threatens Seafood
NOAA, United States Coast Guard, AP Photo/Edd
On March 18, 1967, the
entire cargo of 119,000 tons of Kuwait crude oil was lost after the tanker ran aground on Pollard Rock on the Seven Stones Reef off of Lands End, England. The Royal Navy dispatched a clean-up response team within four hours of the grounding. By March 26, the entire vessel had broken apart, putting an end to any hopes of towing the ship off the reef. The British government eventually decided to bomb it.BLOG: Dolphin Health 'Grave' After BP Oil Spill
In the early morning hours of Dec. 15, 1976, the crew of the aging Liberian oil tanker
could not keep control in the rough waves and 50-knot winds during a storm off the coast of Nantucket. The ship ran aground among the Nantucket shoals. On Dec. 16, the crew was evacuated, and by Dec. 22, the ship had broken into three pieces, spilling all of its 7.7 million barrels of oil into the ocean. Constant bad weather made salvage attempts very difficult, but environmentalists said damage to local waters were minimal. Strong currents carried the oil away from the Massachusetts shoreline and forced it out to sea.BLOG: Record Dolphin, Sea Turtle Deaths Since Gulf Spill
NOAA, National Institute of Health, Associate
Stormy weather, rough seas and a faulty piece of steering equipment proved to be a fatal combination for the
on March 16, 1978. The enormous vessel -- carrying almost 2 million barrels of oil -- was sailing from the Arabian Gulf to Le Havre, France when it ran aground on Portsall Rocks, three miles off the coast of Brittany, during a severe storm. The entire cargo spilled into the water, creating an oil slick 18 miles wide and 80 miles long, and it wasn't long before the force of the storm caused the ship to break apart.BLOG: Shipwreck Oil Spill Time Bombs Identified
United Press International; Photo by Hein Hin
The only thing worse than one oil tanker exploding and sinking while at sea, is two oil tankers colliding at sea. During the rage of a tropical storm in the Caribbean, two giant supertankers, the
, each carrying over 200,000 tons of crude oil, collided near the islands of Trinidad and Tobago on July 19, 1979. The impact caused enormous, violent fires to break out over both ships. Between the two ships, 26 crew members died and 280,000 tons of crude oil were spilled into the Caribbean. Fortunately, the spills never reach shorelines.BLOG: World War II Shipwrecks Pose Oil Spill Threat
NOAA, United States Coast Guard, Getty Images
In the Bay of Campeche off the coast of Mexico, 600 miles south of Texas, the company Petroleos Mexicanos (PEMEX) was drilling a 2-mile-deep oil well called IXTOC I. On June 3, 1979, a loss of drilling mud circulation forced a blowout, causing oil and gas to spew out of the well and ignite. The platform holding the drilling equipment and collecting the oil immediately caught fire and collapsed into the water. Several rescue crews worked for days to try to reach the Blowout Preventer (BOP) -- a large valve used to seal off the surface of a wellhead -- but poor visibility, debris and a long pipeline made it difficult. The IXTOC I well continued to spill oil at a rate of 10,000 to 30,000 barrels per day until it was finally capped on March 23, 1980 -- nine months after the initial incident. By the time it was capped, over 140 million gallons of oil had seeped into the bay, making it the second worst oil spill disaster in history.
Environmental Protection Agency, Associated P
Kuwait oil spills during the Gulf War remain the worst examples of eco-terrorism and are by far the worst oil disasters in history. Beginning in January 1991 during the Gulf War, the Iraqi Army deliberately spilled millions of barrels of oil in the Persian Gulf. Over 500 Kuwaiti tankers, oil fields and refineries were torched, and 3 to 6 million barrels of oil went up in smoke on a daily basis at the peak of the burnings. One 6-million-barrel spill covered over 600 square miles of water and the oil traveled as far as 20 miles away out into the Indian Ocean. The environmental and health risks were enormous, with over 90 million barrels of oil lost. Environmental experts deemed the incident 25 times more toxic than the Exxon Valdez.BLOG: Gulf Hit with Dirty Blizzard After Oil Spill
United Nations Environmental Programme, NOAA,
On April 11, 1991, while unloading crude oil onto a floating platform seven miles off the coast of Genoa, Italy, the MT
exploded, burned for three days and then sank, spilling over 42 million gallons of oil in its wake into the Mediterranean Sea. The Italian and French coastlines were polluted for 12 years after the accident.
Universidad de la Coruña, NOAA, Getty Images
When the huge oil tanker
wrecked about 130 miles of the coast of Galicia, Spain during a storm on Nov. 19, 2002. The ship broke apart and sank to the bottom as it spilled over 1.5 to 2 million gallons of oil into the Atlantic Ocean. Three massive "black tides" soiled 125 miles of Spanish coastline within two weeks after the accident. Considered to be twice as big as the
accident, the Prestige accident remains the worst oil spill in Spain's history.
USGS, Associated Press
An oil well blow out in the Gulf of Mexico on April 20, 2010, caused an offshore oil drilling platform to explode and sink, killing 11 men onboard. Government scientists declared the Deepwater Horizon spill the largest in U.S. history -- with twice as much oil spilled than in the Exxon Valdez disaster.PHOTOS: Alarming Images of Oil-Drenched Gulf
Four years after a BP oil rig exploded and flooded the Gulf of Mexico with an estimated 170 million gallons of oil, scientists have discovered further evidence of coral communities affected by this environmental disaster.
Scientists at Pennsylvania State University, in State College, Pa., found coral communities that show signs of damage from 2010's Deepwater Horizon oil spill more than 12 miles (20 kilometers) from the disaster site. The new findings suggest that the oil spill's footprint is both deeper and wider than was previously thought.
"This study very clearly shows that multiple coral communities, up to 22 kilometers [13.7 miles] from the spill site and at depths over 1,800 meters [5,905 feet], were impacted by the spill," Charles Fischer, a professor of biology at Penn State and co-author of the study, said in a statement.
To locate additional coral communities that may have been affected by the spill, Fischer and his team used 3D seismic data from the Bureau of Ocean Energy Management. They identified 488 potential coral habitats within a 25-mile (40 km) radius of the spill site, and from that list selected 29 sites that may have been impacted by the 2010 disaster. [Images of Coral Damaged by Deepwater Horizon Spill]
Using a specially designed digital camera, called a tow system, as well as a robotic submarine, the researchers captured underwater images of the ocean floor. Where coral sites were found, the team used a remotely operated vehicle (ROV) to collect high-resolution images of the corals.
The researchers then compared images of new coral communities with previously collected data of a coral community affected by the 2010 spill. These older coral images served as a model "fingerprint" for gauging the impact of the spill on newly discovered coral.
"With the camera on board the ROV we were able to collect beautiful, high-resolution images of the corals," Fischer said. "When we compared these images with our examples of known oil damage, all the signs were present providing clear evidence in two of the newly discovered coral communities of the impact of the Deepwater Horizon spill."
Unlike other organisms whose remains sink to the ocean floor and quickly disappear, corals form a mineralized skeleton that can last for years after the organisms die, according to the researchers.
"One of the keys to coral's usefulness as an indicator species is that the coral skeleton retains evidence of the damage long after the oil that caused the damage is gone," Fischer said.
In their search for coral communities affected by the 2010 oil spill, the researchers also found two coral sites entangled with commercial fishing lines. This discovery serves as a reminder that, in addition to the Deepwater Horizon oil spill, marine species in the Gulf of Mexico continue to be harmed by a wide range of human activities, the researchers said.
The study was published online July 28 in the journal Proceedings of the National Academy of Sciences.
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