the past few decades – due to the reduced sea-ice cover on the Arctic Ocean in summer, to higher water and air temperatures, and to rising sea levels. Less sea ice means e.g. that winds produce larger waves [...] in the Arctic is insulated by water and sea ice, one might assume there was no permafrost there. But guess again: at the bottom of certain shallow coastal seas, the ground is permanently frozen. This type [...] there was so much water frozen in the massive inland ice sheets of Scandinavia and North America that in some places, the sea level was 120 metres lower than today. Where now we see ocean waves, there was