Why the Arctic is melting: powerful earthquakes could be the cause of rapid warming

The Arctic is melting due to powerful underground earthquakes

The researchers from the Moscow Institute of Physics and Technology found a new explanation for the rapid warming of the Arctic. They believe that the melting process is influenced by a series of strong earthquakes. Global warming is one of the most important problems of the modern world. It is believed that a people and their activities had a significant impact on it. Various manufacturing processes increase the concentration of greenhouse gases in the atmosphere.

But there are cases of a sharp rise in temperature, and it is difficult to find an explanation for that. In the Arctic, methane emissions are considered to be an important factor in climate change.

It rises to the surface from permafrost in the shelf zone. Since the moment the scientists began to analyze the state of the temperature background in the Arctic, there we’re two sharp periods of warming. The first occurred in the 20s and 30s of the last century. The second one began in the 80s and continues to this day. One of the researchers, Leopold Lobkowski, believes that the hypothesis of the presence of geodynamic factors that create sudden temperature changes should be considered.

For example, a series of strong earthquakes in the Aleutian arc could cause warming. The hypothesis was tested by analyzing three different situations. Did earthquakes coincide with temperature jumps? It turned out that yes.

The scientists also asked about the mechanism that could disturb the lithosphere at a distance of more than two thousand kilometers from the Aleutian Islands to the Arctic shelf. And could these seismic disturbances cause an increase in methane emissions? All questions were answered using historical data. The scientists found that each of the earthquakes recorded in the Aleutian arc in the 20th century was preceded by a sharp rise in temperatures. This was also proved by the created model of the dynamics of excitation of the lithosphere.

With its help, the experts studied the propagation of tectonic waves, while calculating their speed. It was about 100 kilometers a year. This is consistent with the delay between each series of strong earthquakes and the subsequent rise in temperature, as the disturbances took 15 to 20 years to transmit over 2000 kilometers. Further, the scientists found out that deformation waves that are formed in the shelf zone form stresses in the lithosphere.

There are enough of them to destabilize the structures of gas hydrants accumulating methane. As a result, methane enters the water on the shelf and into the atmosphere, which leads to a warming of the climate in the region due to the greenhouse effect.

Reference: “Seismogenic-Triggering Mechanism of Gas Emission Activizations on the Arctic Shelf and Associated Phases of Abrupt Warming” by Leopold Lobkovsky, 29 October 2020, Geosciences. DOI: 10.3390/geosciences10110428