Methane, for the most part, isn’t a gas we’d like to find more of on Earth. Although it decays a lot faster in the atmosphere than carbon dioxide, it warms the planet 28-36 times faster per unit. So when researchers from Queen Mary College London (QMUL) announce that they’ve found a record-breaking pool of it within the Pacific Ocean, you know it’s anything but good news.
Collecting sediment from the seafloor, the team of QMUL geoscientists confirmed that this source of methane can be found stretching all the way from the western coast of Guatemala to the shores of Hawaii, a distance of around 8,000 kilometers (almost 5,000 miles).
As they note in the journal International Society for Microbial Ecology, this is the largest marine methane deposit in the world.
Methane comes from a variety of sources. Cattle produces a heck of a lot of it, as do termites. A lot of the world’s methane, though, comes from natural sources – trapped within the permafrost regions of Siberia and North America, and, in this case, locked up in the sediments of the deep ocean.
These caches are normally created when certain microbes break down organic matter under low oxygen conditions. Over time, their methane expulsions build up and often get frozen into place as solid compounds named “methane hydrates.” When the overlying water or ice gets warmer or more acidic, these stores become unstable and begin leaking.
Craters off the coast of Norway reveal that when this methane becomes particularly unstable, it explodes. These blasts aren’t just rather loud and deadly to anything nearby, but they also transform a lot of that methane into carbon dioxide, the primary antagonist driving climate change.
The zone marked 'ETNP roughly marks the position of the methane cache.
Around 56 million years ago Earth went through a rapid warm period, heating up by 5 to 8°C (9 to 15°F) in just 20,000 years. The so-called Paleocene-Eocene Thermal Maximum (PETM) triggered several significant extinction events, and part of the blame has been placed on huge stores of methane hydrates going up in smoke.
The PETM’s unusually high rate of warming equates to 0.025°C per 100 years. The current pace of man-made global warming is at least 40 times faster. So although our own efforts to boil the planet are proving to be far more effective, any sudden methane release from the hydrosphere or cryosphere would give it a real shot in the arm – and the warmer the world gets, the more likely this is to happen.
So this colossal cache of methane, then, is a no good, very bad, terrible thing. If there are any supervillains out there, we’d suggest going to find it and setting it all alight – if you’d like to watch the world burn, anyway.