Possible Seismogenic-Trigger Mechanism of Methane Emission, Glacier Destruction and Climate Warming in the Arctic and Antarctic.

Abstract–A seismogenic-trigger mechanism is proposed for the activation of methane emission on the Arctic shelf in the late 1970s, which caused the onset of abrupt climate warming in the Arctic and a rapid disintegration of West Antarctica's ice sheet and ice shelves in the late 20th and early 21st centuries. This process is accompanied by the release of methane from the underlying hydrate-bearing sedimentary rocks and accelerated climate warming in Antarctica. The proposed mechanism is associated with the action of deformation tectonic waves in the lithosphere–asthenosphere system, caused by strong earthquakes occurring in the subduction zones closest to the polar regions: the Aleutian, located in the northern part of the Pacific Ocean, the Chilean and Kermadec-Macquarie, located in the southeastern and southwestern parts of the Pacific lithosphere. Disturbances of the lithosphere are transmitted at an average velocity of about 100 km/yr over distances as long as 2000–4000 km, and the associated additional stresses that come to the Arctic and Antarctica several decades after earthquakes lead to the destruction of metastable gas hydrates located in the frozen rocks of the Arctic shelf or in the subglacial sedimentary rocks of Antarctica, causing the greenhouse effect and climate warming. Moreover, transmission of additional stresses causes a decrease in the adhesion of the ice sheet to the underlying rocks, its accelerated sliding and the destruction of the ice shelves in Antarctica. The considered hypothesis leads to the conclusion that in the coming decades, the processes of glacier destruction and climate warming in Antarctica will increase due to an unprecedented increase in the number of strong earthquakes in the subduction zones of the South Pacific Ocean in the late 20th and early 21st centuries. [ABSTRACT FROM AUTHOR]