When the climate change discussion turns to greenhouse gasses, carbon dioxide (CO2) tends to dominate the headlines and generally suck the air out of the room. And rightfully so since according to the Environmental Protection Agency it accounted for 82% of U.S. greenhouse gas emissions in 2017. Next on that list was methane (CH4) coming in at 10%.
While the discrepancy in total volume between CO2 and methane is huge, the actual impact is a bit misleading because per an assessment report from the IPCC (Intergovernmental Panel on Climate Change) methane’s impact is 34x greater than carbon dioxide over a 100-year period meaning a small amount of methane has an outsized influence climate change over CO2.
Methane in the News
Given methane’s role as a power-player greenhouse gas, recent news out of Arctic Ocean should concern anyone who cares about the health of our planet and the climate. Methane is often trapped in permafrost, including underwater, and the warming climate is increasingly melting this permafrost releasing its stored-up methane in the process. The process itself is natural and common, but the rate at which permafrost is melting continues to increase due to global warming.
This phenomenon was recently observed by a Russian research team from Tomsk Polytechnic University which found what the team described as most powerful methane gas fountain ever found. The undersea leak – known as a “seep” – covered an area around 50 square feet east of Bennett Island in the East Siberian Sea creating a methane concentration in the air up to 16 parts per million which is more than nine times the atmospheric average. The research team said the seep resulted in bubbles of methane across the area that made it look like the seawater was boiling.
“This is the most powerful seep I have ever been able to observe,” lead scientist Igor Semiletov – a veteran of 45 Arctic expeditions — said in a statement. “No one has ever recorded anything similar.”
Finding the largest methane seep ever may be a harbinger of things to come. A separate Russian study found over the last 30 years the thawing of underwater permafrost has doubled reaching 18 centimeters per year. Methane-laden permafrost is found under most of the Arctic Ocean and two-third of Russian territory and it has been thawing at an alarming rate because the Arctic is warming at double the rate of the rest of the world. This warming has led to issues such as cracking buildings, broken pipelines, adversely affected agriculture, reintroducing ancient diseases, and releasing methane according to a Telegraph report.
One danger around melting permafrost that concerns climate scientists is likelihood of a positive feedback loop where increasing temperatures in Arctic cause permafrost to melt at increasing rates releasing ever higher levels of methane which directly creates even more warming. The cycle is vicious and feeds itself by ramping up the greenhouse gas concentration in the atmosphere.
Scientists believe a separate feedback is also contributing to the rate the Arctic is warming where higher temperatures are melting more of the ice cover each year exposing more open ocean. The reflective surface of ice helps keep atmospheric temperature’s down, but the darker open ocean water uncovered by melting sea ice absorbs more sunlight warming the entire ecosystem. The combined feedback loops of melting sea ice and melting permafrost are contributing to the rapid warming of the Arctic.
These Arctic effects aren’t limited to Russia, this year scientists said the Canadian Arctic is melting 70 years ahead of schedule per EcoWatch.
In the greenhouse gas conversation carbon dioxide gets almost all the attention, and it definitely has the dubious distinction as the top greenhouse gas. Methane in its own way is more of a silent killer. It not only flies under the greenhouse gas radar for the most part, it’s also more potent and more difficult to eradicate. Unlike CO2 which people create in volume lending it to reduction policies, methane is largely trapped in the planet like in permafrost and is released when there’s a disruption such as the rapidly melting Arctic permafrost.
Written by David Kirkpatrick