Scientists and technicians from QMUL and the National Oceanographic Centre (Southampton) on the working deck of the RRS James Cook. Photo: Myrsini Chronopoulou

By John von Radowitz
27 February 2017 (Irish Independent) – Microbes are generating a vast pool of marine methane that is contributing to global warming, scientists have confirmed. Scientists from Queen Mary, University of London, traced the source of methane in the tropical Pacific Ocean.
Sediment collected from the ocean floor, where there is very little oxygen, revealed how bugs are creating the largest region of marine methane on Earth. Methane is a potent greenhouse gas with 30 times more heat-trapping power than carbon dioxide. Atmospheric levels of methane have increased in the last few decades, partly because of human activity. Scientists are keen to understand natural processes of methane production and consumption to assess the role played by humans. Scientists aboard the Royal Research Ship James Cook spent six weeks mapping the methane pool between Panama and Hawaii. Their findings are published in the International Society for Microbial Ecology journal. “It’s the first time anyone has successfully retrieved sediment from this part of the ocean and directly measured methane production using specialised equipment on board the research ship,” Dr Felicity Shelley said. “It is important we understand how microbes produce and consume this powerful greenhouse gas, especially in the oceans, where we understand very little.”

Ocean microbes making global warming worse

28 February 2017 (Queen Mary, University of London) – Methane is a powerful greenhouse gas, and a major contributor to increasing global temperatures. The largest pool of marine methane on Earth spans from the coast of Central America to Hawaii in the Tropical Pacific Ocean. The atmospheric concentration of methane has increased over the last few decades and human activities have played an important role in this trend. Scientists are keen to understand the natural production and consumption of methane, which will help to assess the extent of human impact on these natural processes. The team from QMUL’s School of Biological and Chemical Sciences carried out the work on a research cruise. They set sail from Panama aboard the RRS James Cook, and collected sediment from the seafloor and mapped the methane pool in the top 1000m of oceanic water over six weeks.

Mapping methane from microbes

Writing in the journal for the International Society for Microbial Ecology, the team describe for the first time how microbial methane production in parts of the seafloor, where the water is very low in oxygen, feeds a vast methane pool which extends from Panama, up to Mexico and as far out as the Hawaiian archipelago. Joint lead author Dr Felicity Shelley, from QMUL’s School of Biological and Chemical Sciences, said: “The research is novel because it’s the first time anyone has successfully retrieved sediment from this part of the ocean and directly measured methane production using specialised equipment on board the research ship.” “It is important that we understand how microbes produce and consume this powerful greenhouse gas, especially in the oceans where we currently understand very little.” The research was funded by the Natural Environment Research Council (NERC).

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