On the surface, the idea of climate change and earthquakes being connected feels like a bit of a stretch. After all, the temperature below the surface of the Earth is rather stable and doesn’t seem to be affected by the annual four seasons.
When I first read about the frozen tundra thawing, my mind immediately turned to a potential increase in earthquakes. My mind pictured an inflated balloon that a child is sitting on. The balloon’s shape is distorted from its “relaxed” state when no outside pressures are applied to it. Now consider if the child sat on the balloon long enough for a thin coat of Elmer’s glue to be applied over its surface. Once the glue dries, it is a bit like the Earth’s crust.
Then, after the glue has dried, the child grows tired of playing with the balloon and gets up. The balance of the glue and the pressure of the balloon are no longer in harmony. As the balloon relaxes back to its original shape, the glue will be stressed. So stressed, it will most likely break and crack, forming chasms along the surface.
How does this coincide with climate change and earthquakes? The frozen tundra around the Arctic is over a mile deep in places. That much ice is a lot of pressure on the surface of the Earth, kind of like a child sitting on a balloon. Once the tundra starts to thaw, the pressure is distributed to other parts of the Earth. In the same way, the balloon snaps back to its original shape after the child gets up, and so does the Earth snap back to its original shape before the frozen tundra is formed.
As the Earth snaps back to its original shape, the Earth’s surface will develop stress and distortion in places that have been undisturbed for millions of years. This will, in my mind cause a considerable number of earthquakes as the Earth works to rebalance itself to its original shape.
Granted, the balloon comparison is drastic compared to the deformation of the Earth due to the frozen tundra, but the effect is measurable. There are studies related to an increase in earthquakes when the sun and moon are on the same side of the Earth. Thus, just the small amount of extra gravitational pull by having the sun and moon aligned can alter the delicate balance of a moving tectonic plate. If such a small event can cause an increase in earthquakes, how much more likely is the thawing of hundreds of feet of ice?
One of my favorite documentaries on climate change and the frozen tundra is Artic Sinkholes by NOVA.