Both the spill and the cleanup efforts had effects on the environment. The oil spill was called the "worst environmental disaster the US has faced" by White House energy adviser Carol Browner. The spill was by far the largest in US history, almost 20 times greater than the usual estimate of the Exxon Valdez oil spill Apr 20, · The leak pumped out 12 times more oil than the Exxon Valdez spill of U.S. Coast Guard fire boats crews battle the blazing remnants of the offshore oil The Exxon Valdez Oil Spill; In the month of March 24, , Research categorizes it as one of the most destructive human caused environmental disasters with both the long-term and short-term effects. The instant outcome was the deaths of , to as many as , seabirds, at least 2, sea otters, harbor seals, Bald Eagles
Alaska | NOAA Fisheries
The Deepwater Horizon oil spill in the Gulf of Mexico has been described as the worst environmental disaster in the United Statesreleasing about 4. Both the spill and the cleanup efforts had effects on the environment. The oil spill was called the "worst environmental disaster the US has faced" by White House energy adviser Carol Browner. Most of the impact was on the marine species. Eight U. national parks were threatened [4] and more than species that live in the Gulf islands and marshlands are at risk, including the endangered Kemp's ridley turtle, the green turtlethe loggerhead turtlethe hawksbill turtleand the leatherback turtle.
In the national refuges most at risk, about 34, birds were counted, including gullspelicansroseate spoonbillsegretsternseffects of the exxon valdez oil spill term paper, and blue herons.
The area of the spill includes 8, species, including more than 1, fish, birds, 1, molluscs, 1, crustaceans, 4 sea turtles, and 29 marine mammals. Threatened species, the report found, ranged from 'whale sharks to seagrass". Also another impact to marine species was the impact to various food chains.
With one break in the chain, the rest of the chain could be impacted greatly. Harry Roberts, a professor of Coastal Studies at Louisiana State Universityhas stated that 4 million barrelsm 3 of oil would be enough to "wipe out marine life deep at sea near the leak and effects of the exxon valdez oil spill term paper in the Gulf" as well as "along hundreds of miles of coastline.
The actual number of mammal deaths due to the spill may be as much as 50 times higher than the number of recovered carcasses, according to a study published in the Journal Conservation Letters. This is because reports have implied that the number of carcasses recovered equals the number of animals killed by the spill" stated Rob Williams from University of British Columbia.
On 22 Octoberit was reported that miles-long strings of weathered oil had been sighted moving toward marshes on the Mississippi River delta. Hundreds of thousands of migrating ducks and geese spend the winter in this delta. Preliminary evidence showed the vast majority of the small sample of pelican eggs tested contained "petroleum compounds and Corexit". Fish and Wildlife Servicethe cause of death had not been determined as of late June. According to NOAAsince 1 Januaryeffects of the exxon valdez oil spill term paper, 67 dead dolphins had been found in the area affected by the spill, with 35 of them premature or newborn calves.
An NOAA study in springalong with two other studies reported at the same time, suggests that the long-term environmental effects of the spill may have been "far more profound than previously thought". The joint study by NOAA and BP found "many of the 32 dolphins studied were underweight, anemic and suffering from lung and liver disease, while nearly half had low levels of a hormone that helps the mammals deal with stress as well as regulating their metabolism and immune systems". Researchers found that some types of spiders and other insects were far less numerous than before the spill.
During a January flyover, former NASA physicist, Bonny Schumaker noted a "dearth of marine life" in a radius of 30 to 50 miles 50 to 80 km around the Macondo well.
few sharks, few bait balls, all of the things we used to see," she commented. This may mean that the wildlife left the area in search of food. Three years after the oil spill, the residual effects were still apparent, with tar balls still found on the Mississippi coast, as well as an oil sheen along a coastal marsh, and erosion on an island in Barataria Bay sped up by the death of mangrove trees and marsh grass.
In February 26th, federally funded scientists found damage to deep sea coral several miles from the well. Expedition leader and biologist with Penn State University Charles Fisher said there was "an abundance of circumstantial data" suggesting coral damage is related to the spill. This discovery indicated that the spill's ecological consequences may be greater than was previously officially claimed.
In Marchdefinitive link was found between the death of a Gulf coral community the size of half a football field and the spill. In Februarythe first birthing season for dolphins since the spill, the director of the Institute for Marine Mammal Studies in Gulfport reported that dead baby dolphins were washing up along the Mississippi and Alabama shorelines at about 10 times the normal number for the first two months of the year.
This year we have 17 and February is not even over yet. From mid-January to late Marchscientists counted almost dead dolphins in the Gulf, with another 90 in After investigating the deaths, NOAA put a gag order on the results, saying that the research is part of a criminal investigation of the spill. Numerous independent scientists said they have been "personally rebuked by federal officials for speaking out of turn to the media about efforts to determine the cause" of the deaths.
In Aprilone year from the onset of the spill, scientists confirmed that they had discovered oil on dead dolphins found along the Gulf Coast. Fifteen of the dolphins that had washed ashore in the last 14 months had oil on their bodies; the oil found on eight of them was linked to the spill.
A NOAA spokesperson said it was "significant that even a year after the oil spill we are finding oil on the dolphins, effects of the exxon valdez oil spill term paper, the latest just two weeks ago. The animals compared unfavorably with dolphins from an area of the gulf unaffected by the spill.
On 12 Aprila research team reported that 88 percent of about baby or stillborn dolphins within the spill area "had abnormal or under-developed lungs", compared to 15 percent in other areas.
The study was published in the April Diseases of Aquatic Organisms. In "disturbing numbers" of mutated fish were seen in the Gulf. they look like they've been burned off by chemicals". The dispersants are known to be mutagenic. Prior to the spill, effects of the exxon valdez oil spill term paper, approximately 0. A paper in the journal Science found that toxins released by the oil spill killed fish by causing cardiac arrest.
The study found that even very low concentrations of crude oil can slow the pace of fish heartbeats. The study was conducted by researchers at Stanford University and the National Oceanic and Atmospheric Administration as part of the federal Natural Resource Damage Assessment process required by the Oil Pollution Act.
It focused on tuna partly because the spill occurred in an area where Atlantic bluefin tuna were spawning. The effects were considered especially problematic for fish embryos and early developing fish, because the heartbeat changes could affect the development of other organs, including the lungs and liver. BP disputed the study, raising questions about the study and the use of its findings in the damage assessment process.
BP responded that the concentrations of oil in the study were a level rarely seen in the Gulf, but The New York Times reported that the BP statement was contradicted by the study. Ina new species of baleen whale known as Rice's whale Balaenoptera ricei was described.
This species has a highly restricted range, currently only being effects of the exxon valdez oil spill term paper from a very small section of the northeastern Gulf of Mexico west of Florida and south of Alabamaand a population somewhere between a several dozen individuals if accounting for the current population and individuals if accounting for unsurveyed areas of the Gulf that could hold undiscovered populations of the species.
Ian MacDonald believes that the natural gas dissolving below the surface has the potential to reduce the Gulf oxygen levels and emit benzene and other toxic compounds. Signs of an oil-and-dispersant mix were found under the shells of tiny blue crab larvae in the Gulf by researchers at Tulane University in This finding indicated that the use of dispersants had broken the oil into droplets small enough to easily enter the food chain.
Marine biologists found "orange blobs" under the shells of crab larvae in "almost all" of the larvae collected from over miles km of coastline stretching from Grand Isle, Louisiana, to Pensacola, Florida. Michael Roman of the University of Maryland Center for Environmental Science stated "traces of oil in the zooplankton prove that they had contact with the oil and the likelihood that oil compounds may be working their way up the food chain".
Scientists commenting on the study, published in PLOS ONEsaid it pointed toward "major future effects of the spill", effects of the exxon valdez oil spill term paper. The PAHs can kill animals immediately, effects of the exxon valdez oil spill term paper high enough concentrations, and can lead to cancer.
Therefore, the effects on the deep sea ecosystem may be considerably more severe than supported by the observations reported here," the researchers wrote in the journal Geophysical Research Letters. PAH's, they said, include a group of compounds, with different types at different depths.
In SeptemberOregon State University researchers found sharply heightened levels of chemicals in the waters off the coast of Louisiana in Augustthe last sampling date, even after the well was capped one month prior. Near Grand Isle, Louisiana, the team discovered that PAH remained at levels 40 times higher than before the spill. The PAH's were most concentrated in the area near the Louisiana Coast, but levels also jumped 2—3 fold in effects of the exxon valdez oil spill term paper spill-affected areas off Alabama, Mississippi and Florida.
As of AugustPAH levels remained near those discovered while the spill was still flowing heavily. Jim Cowan of Louisiana State University 's Department of Oceanography and Coastal Sciences, believes PAHs, weathered from leaked oil on the seabed, are likely the cause of the mutations. A study of the effects of the oil spill on bluefin tunapublished in the journal Scienceclarifying the mechanics by which PAH kill fish, found that the toxins from oil spills can cause irregular heartbeats leading to cardiac arrest.
It found that PAHs block signaling pathways that allow potassium and calcium ions to flow in and out of cardiac cell membranes and sustain normal heart rates, effects of the exxon valdez oil spill term paper, and that even very low concentrations of crude oil can disrupt these signaling pathways, slowing fish heartbeats, effects of the exxon valdez oil spill term paper.
The study found that cardiotoxicity might have been widespread in animal life exposed to the spill. The oil from the disaster affected between and miles of the United States coastline around the Gulf of Mexico and has acutely catalyzed the erosion of land due to the oil having led to the death of most of the marsh vegetation effects of the exxon valdez oil spill term paper. This could result in long-lasting effects to the ecosystem.
The lead author said, "We went from this very diverse community with an abundance of different organisms to this really impoverished community that was really dominated by a couple of fungal species". The authors also expressed concerns that trace minerals and metals such as mercury and arsenic effects of the exxon valdez oil spill term paper by the oil may cause harm to both wildlife and humans.
The use of dispersant made oil sink faster and more deeply into the beaches, and possibly groundwater supplies, according to a November a study released by Florida State University and Utrecht University in the Netherlands. The researchers found that Corexit A allowed the PAHs to permeate sand where, due to a lack of sunlight, degradation is slowed. The oil clean-up itself caused damage to the fragile environment. In Orange Beach Alabamabeach erosion and disruption of plant and animal life-cycles continued intodespite repeated requests by the mayor and other local officials to leave the area.
Clean-up crews deterred tourists from visiting local hotels and beaches due to an increase in criminal activity caused by the influx of clean-up workers. A Coast Guard report released on 17 Decembersaid that little oil remained on the sea floor except within a mile and a half 2. Charlie Henry of NOAA warned even small amounts of oil could cause "latent, long-term chronic effects".
Ian R. MacDonald of Florida State University said even where the government claimed to find little oil, "We went to the same place and saw a lot of oil. In our samples, we found abundant dead animals. After Hurricane Isaac in Septemberaboutpounds of oiled material traced to the spill was brought to land.
This was a greater amount than had been collected in the eight months prior. Huge [ quantify ] tar mats were also uncovered during the storm, prompting beach closures.
Although some researchers thought that the effects of the exxon valdez oil spill term paper from the spill would rapidly resolve, three years into the recovery dolphins continue to die, fish are showing strange lesions, corals in the gulf have died and oil still remains in some marsh areas. At the "Gulf of Mexico Oil Spill and Ecosystem Science Conference", oceanographer David Hollander presented data that showed as much as one-third of the oil released during the spill may still be in the gulf.
Researchers described a phenomenon called "dirty blizzard": oil caused deep effects of the exxon valdez oil spill term paper sediments to clumped together, falling to the ocean floor at ten times the normal rate in an "underwater rain of oily particles". The result could have long-term effects on both humans and marine life. Commercially fished species feed on sediment creatures, meaning oil could remain in the food chain for generations.
Inresearchers found that a tiny amoeba-like creatures, foraminiferathat live in sediment and form the bottom of the gulf food chainhave died off in the areas that were affected by the underwater plumes that stretched out miles beyond the spill site.
The foraminifera have returned in some areas but in other areas they have burrowed into the sediments, effects of the exxon valdez oil spill term paper, stirring them up all over again. Noting that it took several years for the herring population to crash following the Exxon Valdez oil spill, the researchers expressed concerns that it may also take years for long-terms effects to become apparent in the gulf. From Wikipedia, the free encyclopedia. This article is part of a series about the Deepwater Horizon oil spill BP Deepwater Horizon Explosion Oil spill Timeline Volume and extent Closure Response Environmental impact Health consequences Economic effects Reactions Investigation Litigation Compensation v t e.
Lingering Impact of Exxon Valdez Oil Spill
, time: 1:56Top 15 Worst Environmental Disasters Caused by Humans - Conserve Energy Future
May 19, · Exxon Valdez Oil Spill Trustee Council "Legacy of an Oil Spill: 20 Years after Exxon Valdez," blogger.com, Mar. 24, Jan. 23, - Congress Passes Act to Stimulate Development of Hydrogen Power The most publicized environmental effect of using petroleum as a fuel is oil spills, highlighted by the spill of 40, tons of oil from the tanker Exxon Valdez off the coast of Alaska in Although over a billion dollars was spent in the clean-up, many of the beaches were ruined and numerous species of aquatic animals suffered damage that Alaska, a region of nearly million square miles includes waters in the Gulf of Alaska, Bering Sea, Aleutian Islands, Chukchi Sea, and Beaufort Sea
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