They investigate the risk of increasing methane emissions from shallow Arctic waters

Sampling of high methane levels in seawater in the East Siberian Arctic Ocean in October 2020. Photo: Örjan Gustafsson

Forecasting requires knowledge

In order to prevent the Earth's climate change from entering a phase that would cause great difficulties for future generations, it is crucial, according to the research, that the Earth's total greenhouse gas emissions remain within the remaining "emissions budget" set by the UN Climate Panel. However, how large future emissions will be is an area that needs to be studied in more detail if the emissions budget is to be realistic.

”The margin for emissions may in fact be smaller than estimated because of increasing emissions of, among other things, the potent greenhouse gas methane from Arctic systems. These are emissions that were not included in the calculations in the Paris Agreement when estimating how little greenhouse gases we can afford to continue emitting before we need to reach net zero emissions,” says Örjan Gustafsson, professor of biogeochemistry at the Department of environmental sciences and the Bolin centre for climate research at Stockholm University.

Thawing of old coastal permafrost in the northeastern Siberian-Arctic Ocean releasing greenhouse gases. Similar processes occur in seabed permafrost due to thawing from seawater. Photo: Igor Semiletov

Several major expeditions

Major advances in understanding the interconnected cryosphere-climate methane system depend on field-based research, but expeditions are challenging in a geopolitically difficult time with many ongoing conflicts. Therefore, Stockholm University's large data and sample collection is an important source of knowledge for researchers around the world.

”After several large research expeditions to the Arctic, we now have access to probably the largest collection of relevant data and samples from sediments, seawater and air in the Arctic available outside Russia by international comparison,” says Örjan Gustafsson.

In order to increase the level of knowledge and contribute to more accurate predictions about the future of the complex Arctic climate system, the "TippingArcticOceanMethane" project will analyze sample material and data collected during several major expeditions to key Arctic areas, including the Smirnitsky-2008, Oden-2014 and Keldysh-2020 expeditions.

Joined forces

Three internationally leading climate researchers at Stockholm University are joining forces to provide analyses at a particularly high research level: Örjan Gustafsson, professor of biochemistry, and Birgit Wild, associate senior lecturer, both at the Department of environmental sciences, and Weili Hong, associate senior lecturer in geochemistry at the Department of geological sciences. Key research questions, which will be matched with concrete measurements and observations, include where in the seafloor the largest sources of methane emissions are located and why thawing appears to be faster in the seafloor than on land. The results will also be mapped geographically to look for patterns in where the elevated levels are located.

”The permafrost and methane hydrates in the seabed are thought to contain huge amounts of methane that could be released into the shallow Arctic seas and, in the worst case, even into the atmosphere. We hope to gain a better understanding of how these systems work and whether there is a risk of a dramatic increase in methane emissions in the near future,” says Örjan Gustafsson.

Read more about the research of Örjan Gustafsson