A megatsunami crashed over the shores of Dickinson Fjord on the eastern coast of Greenland, reaching a wave height of over 656 feet.

It started with a melting glacier, which set off a landslide, which triggered a 650-foot high mega-tsunami in Greenland. Then came something inexplicable.

New research explains what exactly happened a year ago, when large seismic waves from Greenland caused the earth to tremble for nine days and the movement was detected at monitoring stations worldwide — including in Yellowknife.