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Correlation of CO2 in atmosphere, seawater and seawater pH (acidity)
In a new study marine scientists have warned that the rate of ocean acidification presently occurring is unprecedented in the last 300 million years.
This is due to dissolving carbon dioxide from the atmosphere, much of
which human activity has contributed over the last 200 years through the
use of fossil fuels.
The extent and rate of acidification enhances the prospect for a mass marine extinction event this century. Research in paleoclimatology and oceanography has revealed that anthropogenic climate change is driving Ocean Acidification threatening marine ecosystems.
The oceans act as a great carbon sink which has been good for slowing
the presence of carbon dioxide in the atmosphere and moderating the
greenhouse effect which causes global warming. That is one reason why we
have only experienced a 0.8C rise in average global temperatures over
the last 100 years. More...
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Image by Getty Images via @daylifeWaste Management workers are out and about when almost everyone else is not. Except someone who might be up to no good.
Image by NASA's Marshall Space Flight Center via FlickrBP and the government decided that millions of gallons of dispersants should be dumped into the Gulf to sink and hide the oil.
They succeeded in sinking it. As ABC, CBS and NPR note, huge quantities of oil are blanketing the ocean floor, killing virtually all of the sealife which lives there.
And giant new underwater plumes have been found in the water column itself.
But officials don't want to hear about them. As one member of the oil spill recovery team said:
“My biggest concern is there’s [a plume of oil] five miles by 30 miles out there that was reported and no one responded. The Coast Guard said for days that they wanted to run tests, and if they don’t test it when it’s called in, they’ll never find it.” More...
Just when you thought the damages BP could cause was limited to beaches, marshes, oceans, people's livelihoods, birds and marine life, there's more.
BP's favorite dispersant Corexit 9500 is being sprayed at the oil gusher on the ocean floor. Corexit is also being air sprayed across hundreds of miles of oil slicks all across the gulf. There have been widespread reports of oil cleanup crews reporting various injuries including respiratory distress, dizziness and headaches.
Corexit 9500 is a solvent originally developed by Exxon and now manufactured by the Nalco of Naperville, Illinois. Corexit is is four times more toxic than oil (oil is toxic at 11 ppm (parts per million), Corexit 9500 at only 2.61ppm).
In a report written by Anita George-Ares and James R. Clark for Exxon Biomedical Sciences, Inc. titled "Acute Aquatic Toxicity of Three Corexit Products: An Overview" Corexit 9500 was found to be one of the most toxic dispersal agents ever developed.
According to the Clark and George-Ares report, Corexit mixed with the higher gulf coast water temperatures becomes even more toxic. The UK's Marine Management Organization has banned Corexit so if there was a spill in the UK's North Sea, BP is banned from using Corexit.
The danger to humans can be expected. The warnings on the Corexit packaging is straightforward. Breathing in Corexit is not recommended. More...
The research, combined with other emerging data, could fundamentally alter researchers’ understanding of the oil spill. It suggests that vastly more oil than previously reported could be spilling from the wellhead and the attached riser pipe that now lies crumpled on the seafloor like a kinked and leaking garden hose.
Moreover, it suggests that serious environmental degradation could take place in the open ocean, creating massive “dead zones” where no creature can live because of the lack of oxygen in the water. The spread of oil at all levels of the Gulf also could become a concern for shore communities in hurricanes, which stir up the water column as they come ashore.
Scientists looking at video of the leak, suggest that as many as 3.4 million gallons of oil could be leaking into the Gulf every day – 16 times more than the current 210,000-gallon-a-day estimate, according to the Times.
The fact that the spill could possibly be so radically misunderstood nearly a month after it began speaks to the unique nature of this spill. In particular, it’s depth – 5,000 feet below the ocean surface – makes it both unprecedented and difficult to study.
For experts, “most of their experience is with shallow-water spills that quickly bleed black goo onto beaches that are cleaned up relatively quickly,” says the Los Angeles Times.
That is clearly not what has happened in the Gulf, where shorelines have, so far, emerged relatively unscathed.
The nature of the oil in the Gulf oil spill could be relevant – it is of a lighter grade than that in the Exxon Valdez spill, for example.
More relevant could be the dispersant that BP is applying to the oil at the source. BP officials have hailed the process as a success, noting diminishing oil at the surface. But the dispersant breaks the oil into smaller drops, which might instead be spreading throughout the water column, instead of rising to the surface.
It is not clear what this would mean environmentally, though past research indicates that oil can be trapped in the seabed for decades after oil on the surface is cleaned away.
It would, however, make predictions for the spill far more complex.
"We have no idea where the oil that isn't reaching the surface is going," James Cowan Jr., an oceanography professor at Louisiana State University, to the Los Angeles Times. "It could go everywhere.
The Gulf currents operate differently at different levels, making the exact location and spread of the oil at different depths hugely important to predictions of where it might end up. Indeed, the system so complex that in time, oil could be taken anywhere from the Mexican Coast to Florida’s Palm Beach, research suggests.
BP has so far rejected any efforts toward pinpointing the exact amount of oil entering the Gulf, saying that effort would detract from other containment efforts, such as the current effort to stopper one of the leaks with a siphon. But getting a more accurate sense of how much oil in leaking could be vital to trying to account for all of it, scientists say.
Scientists and ocean advocates stepped up warnings this week of potential dangers from chemical dispersants, as oil giant BP released unprecedented amounts of a classified and toxic chemical to thin the Gulf of Mexico oil slick before it reaches shore.
"Unfortunate recent events in the Gulf Coast have once again brought to the forefront issues pertaining to the impacts of dispersants and dispersed oil," Carys Mitchelmore, a researcher at the University of Maryland Center for Environmental Science, told the Senate Subcommittees on Oversight and Water and Wildlife.
"There's a potential for a toxic soup of unknown effects, which cannot be predicted even if the individual constituents are known."
Response teams have dumped about 436,000 gallons of a chemical dispersant, called Corexit, into the Gulf to battle the leak from BP's sunken Deepwater Horizon ruptured rig—more than has ever been used in the United States.
Some of that is being pumped 5,000 feet underwater at the site of the spill, a deepsea technique that has never been tried. The exact ingredients of chemical dispersants are protected as trade secrets and are unknown.
"Putting this right on the seabed, it's unknown what the consequences will be," said Mitchelmore.
The dispersant, a detergent-like brew of solvents, surfactants and other compounds, breaks down oil into tiny particles that scatter into the sea to prevent crude from washing ashore and wiping out wildlife.
Some analysts describe the chemical stew as a a slow and silent killer, however, quietly altering the balance of food webs, contaminating species and damaging the overall health of the oceans.
John Everett, president of Ocean Associates Inc., a Virginia-based oceans and fisheries consulting firm, said the dispersant could cause more harm than the calamitous spill itself, which is gushing oil at a pace of 210,000 gallons a day and has now exceeded the four-million gallon mark.
"The oil damage will eventually heal. Better procedures will be employed and this oil will be recycled and assimilated," Everett told Congress.
"The flow of chemical materials into our waters is another matter. There are too many insidious contaminants entering our estuaries, causing genetic harm and poisoning our Earth, turtles and seafood."
The harmful chemicals, he said, creep into the food supply and "directly impact us as well."
Soon after the April 20 oil rig blast, U.S. Environmental Protection Agency (EPA) and the U.S. Coast Guard gave BP the greenlight to spray the dispersant on the water's surface and to test it almost a mile under the sea. The chemical was pre-approved for use in the National Contingency Plan (NCP) Product Schedule.
EPA declares that it has "not given authorization for the full scale use of dispersants underwater beyond initial tests to determine its effectiveness." But that could soon change.
EPA Administrator Lisa Jackson told reporters on Wednesday that so far 28,709 gallons of dispersants had been discharged in the seabed for testing purposes. Jackson said the agency is now waiting on results to determine the chemical's effectiveness in decomposing crude at those depths. Two earlier attempts to test the site failed, she said.
"The effect of underwater dispersant still is unknown," Jackson added.
Working with EPA, National Oceanic and Atmospheric Administration (NOAA) said it was examining water samples on the seafloor near the leak.
On the sea surface, the results of EPA's most recent water samples, gathered from April 30 to May 5, showed that "water quality does not pose increased risk to aquatic life."
Speaking to the subcommittees this week, Jim Jones, deputy assistant administrator for the EPA's Office of Chemical Safety and Pollution Prevention, conceded that the dispersant being deployed "has toxicity associated with it" and that "damage has been done."
He called the tests an "environmental trade-off" between long-term harm to offshore wildlife and fragile lands if the spill were to wash ashore, and potential shorter-term damage to some sea life.
Mitchelmore, said the trade-off is simply the "protection of one habitat...at the cost of another."
"In this case, the protection of shoreline species at the expense of organisms residing in the water column and potentially also those at the seabed," she added.
In regard to Corexit, Mitchelmore said, "limited prior toxicological information exists to fully assess risks to exposed organisms."
But both oil and oil spill dispersants are known to cause a variety of health effects in animals, she added, "including death and a variety of sublethal impacts including reduced growth, reproduction, cardiac dysfunction, immune system suppression, carcinogenic, mutagenic and teratogenic effects and alterations in behavior."
Jackson said that Corexit is at most one-tenth "as toxic as oil."
Fishing advocacy groups, meanwhile, such as the eight-state Southern Shrimp Alliance (SSA), are fearful of long-lasting effects of a chemical that could eat away at their livelihoods.
"SSA welcomes testing sediments in the water column as a good first step, but fear the 'act now, check later' approach being taken with dispersants," said John Williams, the group's executive director. "These chemicals relocate the oil from the shores to the water column where it will be spread by currents to vital reproductive grounds throughout the western Gulf of Mexico."
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