A scientific expedition to Antarctica begins to search for methane leaks that enhance global warming

A Spanish scientific team begins a mission in Antarctica to search for and characterize methane gas leaks in the Antarctic Ocean. These leaks are a result of global climate change, which can also influence its acceleration. Such leaks are linked to how solid-state methane gas deposits respond to the retreat of glaciers, a phenomenon that will be investigated in the Antarctic Peninsula during the expedition.

The team is led by the Geological and Mining Institute of Spain (IGME) and the Institute of Marine Sciences (ICM), both entities dependent on the Higher Council for Scientific Research (CSIC) in Spain.

The Iceflame project, which involves the participation of 26 people aboard the Sarmiento de Gamboa oceanographic vessel, will collect data from the ocean floor using seismic probes and sediment samples, at depths ranging from 500 to 4,000 meters. The objective is to locate possible methane leaks. It is a greenhouse gas that generates between 20 and 40 times more global warming than that caused by carbon dioxide (CO2). It last accumulated massively on the Antarctic seabed, in the form of frozen methane (methane hydrates) during the last glacial period, 20,000 years ago.

The existence of these deposits has been known since the 1990s, when international powers explored possible hydrocarbon deposits in Antarctica. However, until now no one has studied in detail how they are reacting to glacial retreat caused by global warming. The loss of ice mass on the continent is known to cause ground uplift. In the marine zone, a decrease in depth, and therefore a reduction in the effective pressure on the bottom, facilitates gas leaks. This could affect the stability of the bottom (geological risks) and have repercussions on the global climate.

Methane hydrates are crystalline solids that look similar to ice (frozen methane). They form at high pressure and low temperatures, common conditions at more than 300 meters below sea level in polar areas. However, Iceflame points out, these conditions make them very vulnerable to changes associated with global warming, which raises the temperature of the ocean and causes the seabed to rise, thus reducing pressure. These hydrates, in addition to influencing global warming, reduce the stability of marine sediments, to the point that instability can cause explosions and large landslides, a geological risk with the potential to generate tsunamis.

The Sarmiento de Gamboa oceanographic vessel. (Photo: CSIC)

Roger Urgeles (ICM) and Ricardo León (IGME), both geologists and principal researchers of the Iceflame project, highlight the importance of their project: “We know of the problems that methane hydrates generate in the Arctic, but no one has investigated them in Antarctica. how we want to do it now. In the Antarctic Peninsula area alone, we estimate that there are about 24 gigatonnes of carbon accumulated in methane hydrates, which is equivalent to the carbon dioxide emissions of human origin for two years on the entire planet. And its state is unknown, we do not know if the frozen, solid methane is transforming into methane gas. “This is what we want to find out in this Antarctic campaign.”

Specifically, for 24 days on board, and 24 hours a day, for which they will be organized in three shifts, they will collect data and samples with probes that will allow us to know the structure of the sediments of the Antarctic Ocean up to a kilometer deep. . How these fluids migrate through the subsoil to the seabed will be investigated and emissions to the water column will be quantified. Another objective will be the analysis of the microorganisms that feed on this gas, thus collaborating positively in the reduction of its emissions, as well as its metabolic products.

The entire team, which also includes Miguel Llorente and Luis Galán from the IGME, in addition to the ICM staff, will remain on board the Sarmiento de Gamboa ship until February 8. “With Iceflame we want to fill that gap in knowledge about the interaction between methane systems and recent environmental changes in Antarctica. We intend that the results of the project contribute not only to climate science, but also to the understanding of the geological and environmental risks associated with deposits that are known to exist but whose stability no one has investigated,” says León. (Source: IGME / CSIC)