The Arctic Ocean has been seeping methane for longer than humans have been roaming the Earth, according to new research published in Geophysical Research Letters.
This gas, emitted among others by burning/drilling natural gas, has been worrying environmentalist groups because a thaw in the Arctic permafrost might free up more methane, accelerating global warming and the Arctic meltdown.
But this new study shows that the Arctic Ocean seabed has been emitting methane for at least 2.7 million years. “We know from other studies in the region that the sediments we are looking at in our seismic data are at least 2.7 million years old. This is the period of increase of glaciations in the Northern Hemisphere, which influences the sediment,” says Plaza Faverola, one of the research, in an interview published on Anthony Watt’s blog.
In other words, the last Ice Age changed the composition of the soil, making it susceptible to emit methane. The study also shows that emissions can be influenced by earthquake activity. These underwater methane columns can be as tall as 800 meters (over 2,600 feet), taller than Dubai’s Burj Khalifa tower, the world’s highest human structure.
These emissions may have influenced temperatures in the past. Researchers believe that bursts of increased temperatures in the past are linked with high methane emissions as shown by studying glaciers.