RECONSTRUCTING THE ORIGIN AND TRAJECTORY OF DRIFTING ARCTIC SEA-ICE

Recent studies have indicated that drifting Arctic sea ice plays an im portant role in the redistribution of sediments and contaminants. Here we present a method to reconstruct the backward trajectory of sea ice from its sampling location in the Eurasian Arctic to its possible sit e of origin on the shelf, based on historical drift data from the Inte rnational Arctic Buoy Program. This method is verified by showing that origins derived from the backward trajectories are generally consiste nt with other indicators, such as comparison of the predicted backward trajectories with known buoy drifts and matching the clay mineralogy of sediments sampled from the sea ice with that of the seafloor in the predicted shelf source regions. The trajectories are then used to ide ntify regions where sediment-laden ice is exported to the Transpolar D rift Stream: from the New Siberian Islands and the Central Kara Platea u. Calculation of forward trajectories shows that the Kara Sea is a ma jor contributor of ice to the Barents Sea and the southern limb of the Transpolar Drift Stream.