Shorelines in the arctic are crumbling and eroding with climate change as the permafrost holding them together melts when sea ice disappears, researchers say.

With sea ice diminishing, waves are pounding the shore and causing the permafrost to thaw, releasing the soil it holds, which is then washed into the ocean, NewScientist.com reported Monday.

A study by the Alfred Wegener Institute for Polar and Marine Research in Potsdam, Germany, says erosion along 62,000 miles of Arctic coast -- nearly a quarter of the total coastline -- is occurring at an average rate of about 20 inches per year.

If the warming climate keeps coastal waters ice-free after summer ends, autumn storms can dig deep into the permafrost, a report issued this week by the International Arctic Science Committee said.

The most dramatic effects have been observed in the Beaufort Sea north of Alaska, where ice-rich bluffs have retreated an average 45 feet a year from 2002 to 2007, already forcing some coastal communities to relocate.