Wall Street Journal: As glaciers melt the Earth’s crust will suffer a “isostatic rebound.” The rebound may cause the planet’s seismic plates to slip and agitate volcanic magma chambers, increasing the likelihood of earthquakes and volcanic eruptions in some areas of the world. “It’s unavoidable that glacial retreat will induce tectonic activity,” says geoscientist Allen Glazner of the University of North Carolina, Chapel Hill.