Sea Bacteria Produce Methane

[Michaelangelica]

[The following is an exact transcript of this podcast.]

 

Methane is a greenhouse gas that traps heat even better than carbon dioxide. It comes from a variety of sources, including fossil fuel production and even farming. Cows give off methane, ya know, after they eat. Even the surface waters of the ocean contain substantial amounts of this gas. But where that marine methane comes was a mystery. Until now.

 

Scientists collected seawater off the coast of Hawaii. And they found that bacteria that live in these waters scarf up certain phosphorous-containing chemicals, and then release methane as a byproduct.

Sea Bacteria Produce Methane: Scientific American Podcast

[modest]

Good info. The paper published in Nature Geoscience (that the podcast above talkes about) is "Aerobic production of methane in the sea", with only the abstract available without registration :evil:

 

Methane is a potent greenhouse gas that has contributed approximately 20% to the Earth's warming since pre-industrial times. The world's oceans are an important source of methane, comprising 1–4% of annual global emissions. But despite its global significance, oceanic methane production is poorly understood. In particular, methane concentrations in the surface waters of most of the world's oceans are supersaturated with respect to atmospheric concentrations, but the origin of this methane, which has been thought to be produced exclusively in anaerobic environments, is not known. Here, we measure methane production in seawater samples amended with methylphosphonate, an organic, phosphorus-containing compound. We show that methane is produced aerobically as a by-product of methylphosphonate decomposition in phosphate-stressed waters. Methylphosphonate decomposition, and thus methane production, may be enhanced by the activity of nitrogen-fixing microorganisms. We suggest that aerobic marine methane production will be sensitive to the changes in water-column stratification and nutrient limitation that are likely to result from greenhouse-gas-induced ocean warming.

 

~modest