Climatic impact of Arctic Ocean methane hydrate dissociation in the 21^st-century

Abstract. Greenhouse gas methane trapped in sub-seafloor gas hydrates may play an important role in a potential climate feedback system. The impact of future Arctic Ocean warming on the hydrate stability and its contribution to atmospheric methane concentrations remains an important and unanswered question. Here, we estimate the climate impact of released methane from oceanic gas hydrates in the Arctic to the atmosphere towards the end of the 21^st century, integrating hydrate stability and atmospheric modeling. Based on future climate models, we estimate that increasing ocean temperatures over the next 100 years could release up to 17 ± 6 Gt C into the Arctic Ocean. However, the released methane has a limited or minor impact on the global mean surface temperature, contributing only 0.1 % of the projected anthropogenic influenced warming over the 21^st century.