Nitrous Oxide Emissions from Ocean Bacteria on the Rise
Largely lost amidst the debate over global warming emissions has been a sufficient focus on greenhouse gases other than the perpetual villain, carbon dioxide. Nitrous oxide, in particular, whose emissions biofuel production is likely to contribute to, has received relatively short shrift; this despite the fact that it is 300 times more potent than carbon dioxide and, unlike the latter, also attacks the ozone layer. A new study by Mark Trimmer from Queen Mary, University of London, may help change that.
He found that a large proportion of the oceans' nitrous oxide emissions is produced by denitrifying bacteria in oxygen minimum zones. Trimmer believes that up to a third of all marine denitrification occurs in the Arabian Sea - an area that also accounts for close to 18% of global oceanic emissions. Nitrous oxide derived from the bacteria living in the Arabian Sea could escape to the atmosphere - contributing to global warming and prompting more frequent bouts of acid rain. He is concerned that the increased export of organic material from the surface waters, spurred by ever-rising levels of atmospheric carbon dioxide, could well expand oxygen minimum zones (by providing a larger source of food for the denitrifying bacteria) and thus lead to rising nitrous oxide emissions.
With biofuel production continuing to gather apace, it will become necessary for industry and governments to tackle rising nitrous oxide emissions - sooner rather than later.
Via ::Queen Mary News: Oceans and streams contribute to global warming (news release)