Glaciers in Svalbard, an archipelago between Norway and the Arctic Circle, are warming twice as fast as the Arctic, which is warming four times faster than the planet. A new study has found that this exceptional warming is in a vicious feedback loop where albedo is lost, warming the ice, melting the glaciers of these islands, and generating a new source of carbon emissions.
. As a result, a new methane feedback loop that feeds on and accelerates itself has been revealed.
People don’t like to talk about methane, but there is yet another source seemingly everywhere you look.
The methane-laced meltwater formed during the glaciers' retreat becomes groundwater below the ice stream. The newly formed groundwater springs previously hidden from science are rich in methane capped by the glacier from being released into the atmosphere. The permafrost in the tundra is capped by frozen soil that keeps methane and CO2 underground.
Once the thinning or rapid retreat of the glacier is enough to expose the surface, methane-saturated water gurgles out and enters the atmosphere as a potent greenhouse gas.
Scientists Gabrielle E. Kleber, Andrew J. Hodson, Leonard Magerl, Erik Schytt Mannerfelt, Harold J. Bradbury, Yizhu Zhu, Mark Trimmer & Alexandra V. Turchyn revealed "methane-rich groundwater springs have formed in recently revealed forefields of 78 land-terminating glaciers across central Svalbard, bringing deep-seated methane gas to the surface." The methane in the ice stream forefront studied is 600,000 times the equilibrium of the atmospheric methane.
This feedback is not in any climate models.
Researchers at the University of Cambridge believe the methane is millions of years old, seeping out from a large reserve of underground gas.
This suggests a lot of greenhouse gas could still be released into the atmosphere — something that hasn't been accounted for in existing climate models.
This isn't the first time scientists have found water spewing methane. In fact, there are lakes in Alaska you can set on fire. These are called thermokarsts and they appear when permafrost thaws.
In the case of thermokarsts, however, the methane comes from microbes that grow in the meltwater. Scientists think the methane in the Svalbard springs comes from somewhere else.
Interesting Engineering explains where the methane source originates.
By analyzing the water chemistry from these springs, the team discovered that nearly all studied sites contained significant amounts of dissolved methane. Consequently, excess methane can escape into the atmosphere when the spring water reaches the surface.
The research findings indicate that the methane emissions from glacial groundwater springs in Svalbard could exceed 2,000 tonnes annually. This estimate represents roughly 10 percent of Norway's annual methane emissions from its oil and gas industry.
"The amount of methane leaking from the springs we measured will likely be dwarfed by the total volume of trapped gas lying below these glaciers, waiting to escape," said co-author Professor Andrew Hodson from the University Centre in Svalbard.
Additionally, "hot spots" of concentrated methane emissions were discovered, which correlated with the rock type where the groundwater originates.
Rock formations such as shale and coal contain natural gases, including methane, formed due to the decomposition of organic matter during the rock's creation. Methane can migrate upwards through cracks in the rock and enter the groundwater.
Yale Climate Connections video on the same methane phenomenon in Greenland’s massive ice cap. The source is decomposing permafrost in Greenland rather than shale rocks in Svalbard.