The warning came as a vast ice shelf, about 260 square kilometres in size, continued to fall away from Greenland's Petermann glacier, the largest iceberg shed by the island in half a century.
The geoscientists told Congress Greenland might cease to exist, with the island rapidly approaching a tipping point that would see much larger masses of ice melting, pushing up the average level of oceans around the world. Temperature rises of between two and seven degrees Celsius - which are considered likely by the end of the century due to human-induced carbon emissions - would force the change, they said. More >>>
