Methane and Climate Change: From the Amazon to the Gulf of Mexico

In surveying the environmental damage unleashed from the BP oil spill, could we be missing the 800-pound gorilla in the closet? While oil poses undeniable ecological risks, methane (CH4) could prove daunting as well. As it turns out, crude which is destroying the Gulf of Mexico contains about 40 percent methane which may suffocate marine life and create vast "dead zones" where oxygen becomes so depleted that nothing is allowed to live.

Methane is a colorless, odorless and flammable substance which forms a major component in natural gas. It is used to heat people's homes, and gets burnt off from crude before oil is shipped to the refinery. Though BP has sought to do just that as it captures crude from its breached well, some of the gas has escaped containment efforts and has wound up in the water. As small microbes living in the sea feed on oil and natural gas, they consume large amounts of oxygen which they require in order to digest food.

That in turn exerts an unfortunate ripple effect: when oxygen levels decrease, the breakdown of oil can't advance any further. What's more, most life cannot survive under such conditions. To make it more concrete, think about the plight of the enigmatic giant squid. Living in deep waters, the squid will be severely disrupted by lower oxygen levels. That in turn stands to have an effect on the food chain, since giant squid provide the meal of choice for endangered sperm whales.

While many will focus on methane's impact upon local wildlife, the compound, also known as marsh gas, also stands to affect climate. Indeed, though some of the methane from the Gulf will dissolve in the water, other parts will be emitted to the Earth's atmosphere. That is a problem, since methane is already contributing to our global warming dilemma. Once in the atmosphere, methane absorbs terrestrial infrared radiation that would normally move into outer space. This phenomenon can contribute to atmospheric warming, which is why methane is considered a greenhouse gas.

Though methane is not as abundant as carbon dioxide, it is twenty times more potent and scientists believe that over the eons it has played a key role in spurring climate change. Some of that history, which has to do with oceans, now pertains to the disaster which we confront in the Gulf. When it is released into the ocean-atmosphere system, methane reacts with oxygen to form carbon dioxide. This in turn may result in something called marine dysoxia, a phenomenon which kills off oxygen-using animals.

Some experts believe that marine dysoxia may be responsible for major oceanic extinctions. "We know that millions of years ago, there were vast undersea eruptions where methane gas escaped just like it is doing right now," says oceanographer John Kessler of Texas A&M University. "It is thought that this methane eventually contributed to climate change," he adds.

Fifty five million years ago, there's evidence of a submarine landslide off the coast of Florida and huge volcanic eruptions under the North Atlantic. That in turn may have released trapped methane which made global temperatures skyrocket by 4-8 degrees Celsius. At the time, summer heat waves scorched the landscape in Spain, giving rise to desert terrain. As far north as England and Belgium, palm mangroves thrived while Mediterranean algae proliferated in the Arctic Ocean.

Though you wouldn't know it from listening to the media, methane has been contributing to global warming more recently. In the tropics, as I disclose in great detail in my recent book No Rain in the Amazon: How South America's Climate Affects the Entire Planet (Palgrave-Macmillan), methane emissions result from such human related (or anthropogenic) activities as livestock and other agricultural practices.

Methane emissions however are also linked to the oil and gas industry. Indeed, right now in the U.S., oil and gas operations represent approximately 23 percent of yearly methane emissions and 2 percent of total greenhouse gas emissions. And while underwater methane emissions are certainly worrying, this is just the tip of the iceberg: every day, the oil industry contributes to global warming simply through its routine operations.

During the production, processing, storage, transmission and distribution of natural gas, methane losses are prone to occur. Moreover, because gas is frequently encountered in association with oil, the production, refinement, transportation, and storage of crude oil is also a source of methane emissions.

As they move abroad, U.S. oil companies exacerbate methane emissions in the tropics. As I reveal in my book, petroleum corporations have set up shop in the Amazon rainforest, thereby contributing to high levels of pollution. In Ecuador, Texaco left a legacy of disease and environmental damage on a massive scale [for a thorough discussion of the issue, see my online review of the recent documentary, Crude]. As part of its operations, the company set up industrial infrastructure including methane gas burn-off stacks. Running 24 hours a day, the stacks turned life into a living hell for local residents.

In the town of Shushufindi, Texaco drilled for oil which brought up massive quantities of methane and tainted water intermingled with oil, heavy metals and oil byproducts. This "production water," which the Indians claimed was cancer-causing, was simply dumped into pits. Indians charged that alongside the Napo River, a tributary of the Amazon, people fell ill from unknown diseases. Manuel Silva, a farmer and environmental activist, told the Boston Globe, "Many people just faint for no reason...It is very common for people to lose their memory, especially the people who live close to the pits and the flares."

In a very general sense, Americans know that oil is polluting though the majority fails to grasp the diverse environmental risks associated with its production. Hopefully, methane emissions from the BP disaster will not result in even greater ecological disaster, yet if anything the environmental tragedy in the Gulf may serve to focus the public's attention on the critical issue of methane.

If there is one silver lining to the Gulf tragedy it is this: methane has a relatively short atmospheric lifetime. As such, the compound is a prime candidate for mitigating global warming over the near-term, say in the next 25 years or so. If and when the authorities manage to get a handle on the BP disaster, it will be high time to engage the public about the need to grapple with this potent but little known greenhouse gas.

Nikolas Kozloff is the author of No Rain in the Amazon: How South America's Climate Affects the Entire Planet (Palgrave-Macmillan). Visit his blog,