A new report has shown that the Arctic Ocean could be a significant contributor of methane to the atmosphere.
The study, published in the journal Nature Geoscience, looked at airborne observations of methane to determine how much of the greenhouse gas was being expelled from the Arctic Ocean, up to latitudes of 82° north.
“We suggest that the surface waters of the Arctic Ocean represent a potentially important source of methane, which could prove sensitive to changes in sea-ice cover,” the authors of the report note.
The Arctic is home to large reservoirs of methane in the form of permafrost soils and methane hydrates. These reservoirs are particularly vulnerable to climate change. As the temperatures warm as a result of greenhouse gases being released into the atmosphere, the permafrost melts releasing methane into the atmosphere which in turn serves to continue the increase in temperatures.
However, the Arctic Ocean methane is a less certain issue.
For example, the paper notes that methane measurements over some parts of the Arctic Ocean were comparable to coastal eastern Siberia where there has been a thaw in the permafrost. Noting that around 10 million square kilometres (3.86 million square miles) of the Arctic Ocean are subject to summer melting of sea ice, “the emissions rate we encountered could present a source of global consequence,” the authors note in the report.
Still, however, the source of the oceanic methane is unclear.