Shelf ice glaciation in the Arctic Ocean? New results from northernmost Greenland

Bounding on the last remaining patch of permanent sea ice and capped by an ice sheet with meltwater sufficient to disrupt the thermohaline circulation, North Greenland is strategically located for contributing to the understanding of the climate system. The coastal plain, which faces the Arctic Ocean, more than 100 km long and 15 km wide, is covered by a continuous blanket of Quaternary sediment that spans at least the period since the last deglaciation c. 9000 years ago, and is capped by an array of glacial and marine landforms. This area therefore contains an unsurpassed source for recording marine and glacial activities along the world's northernmost coast - a source which, owing to its inaccessibility, has largely remained untapped. Preliminary results from the 'LongTerm Project', which ended this summer, show that at least two major glacial events hit the coasts by the end of the last ice age. One of them was possibly a large scale expansion of the Inland Ice resulting in formation of a 100,000 km2 ice shelf in the Arctic Ocean - a type of glaciation, which has usually been thought to be an Antarctic speciality. Even more significantly, abundant accumulations of glacio- fluvial and -lacustrine sediments show that heat transfer to these extreme latitudes by the end of the last ice age was sufficient to allow massive melting of land-based ice. Finally, among the summer's surprises was the discovery of thick piles of raised marine sediments along the coast, allowing a detailed record of sea level history and faunal change, which can be correlated with a terrestrial record from cores, obtained from two lakes on the coastal plain.