Scientists have discovered large amounts of powerful GHG methane from an Icelandic glacier.
A study by the Solheim magnum glacier, which flows from the active volcano Katla, covered with ice, shows that up to 41 tonnes of methane is released through dairy waters every day during the summer months. This is roughly the equivalent of methane that produces more than 136,000 cows.
The study led by the University of Lancaster, which is involved in Scientific reports, is the first published field study showing methane release from glaciers on this scale.
"This is a huge amount of methane that is lost from the glacial melter current in the atmosphere," said Dr. Peter Winne, a studious biogeochemist at the Lancaster Center for Environment and a corresponding author of the study. "It greatly exceeds the average loss of methane from non-lethal rivers to the atmosphere reported in scientific literature. It faces some of the world's methane-producing wetlands and represents more than twenty times more known methane emissions to all other volcanoes in Europe that get together. "
Dr Winne added: "Methane has a global warming potential 28 times greater than that of carbon dioxide (CO2). It is therefore important to know about various methane sources released into the atmosphere and how they can change in the future.
"There is a lot of speculation about whether glaciers can release methane. The glacier's leaf contains perfect cocktail conditions for the production of methane-microbes, low oxygen, organic matter and water-along with an impermeable ice cap surface that keeps methane beneath it.
"However, no one has explored this on the ground so far and this is the strongest proof that glaciers release methane."
The study comes from a PhD. a research conducted by Dr. Rebecca Burns, when she was a graduate researcher at Lancaster University through the Center for Global Eco-Innovation, partly funded by the European Regional Development Fund.
Dr Barnes took samples of water from the edge of a melted water lake in front of the Solihaymokul glacier and measured the methane concentrations, comparing them with methane levels in nearby sediments and other rivers to ensure that methane is not released from the surrounding landscape.
"The highest concentrations were found at the site where the river emerges from below the glacier and enters the lake, indicating that methane must be spawned from the glacier," explains Dr. Winne.
Using a mass spectrometer, which identifies the unique methane imprint, the researchers found that methane comes from a microbiological activity on the glacier's bed. But there is still a connection to the volcano.
"We believe that while the volcano does not produce methane, it provides conditions that allow the microbes to progress and release methane in surrounding milk waters," said Dr Winn.
Normally when methane comes in contact with oxygen, it combines to form CO2, so methane disappears. On the glacier, dissolved oxygen-rich smelters access the bed of the oily mass and convert every methane present in carbon dioxide.
"Understanding the seasonal evolution of the Sollerhicle's subglacial drainage system and its connection to the geothermal area of Cat is part of this work," said Professor Fiona Tweed, an expert in glacier hydrology at Staffordshire University and co-author of the study.
The Sólheimajökull when the blend reaches the glacier, comes in contact with gases produced by the Katla volcano. These gases reduce the content of oxygen in the water, which means that some of the microbial methane can be dissolved in water and transported from the glacier without being converted to CO2.
Dr Hugh Tufen, a volcanologist at Lancaster University and co-author of the study, says: "The Cat's volcano can greatly accelerate the generation of microbial methane, so in fact Katla could be seen as a giant microbiological incubator.
Scientists have also recently discovered that Kat is emitting huge amounts of CO2 – that's the top five globally in terms of CO2 emissions from volcanoes – so Kat is certainly a very interesting, volatile volcano. "
"And Iceland and the Antarctic have many icy, active volcanoes and geothermal systems," says Dr. Barnes. "The recent report by the International Climate Change Panel (IPCC) notes that current trajectories show that global warming is likely to reach 1.5oC between 2030 and 2052, with the highest perceived climate sensitivity at higher latitude." If methane produced under these ice caps there is a means of escaping like ice, there is an opportunity to see short-term increases in the release of methane from the ice masses in the future. "
Andri Stefansson, a professor of hydrothermal geochemistry at the University of Iceland, who was not involved in the study, said: "These findings provide important and new information on the origin and methane flows on the Earth's surface and the significance of this greenhouse effect on the atmosphere from such systems.
However, researchers warn that it is not yet clear how these effects will occur. They believe that although there may be a short-term leap of methane released while the glacier melts and rattles, in the long run the process can be self-limiting, because, together with other reasons, without frost, the methane production conditions have been eliminated.
Observing the development of the deep sea greenhouse gas filter
R. Barnes et al., Direct isotopic evidence for the production of biogenic methane and a moderate glacier efflux, Scientific reports (2018). DOI: 10.1038 / s41598-018-35253-2