EVIDENCE FOR WARMING OF ATLANTIC WATER IN THE SOUTHERN CANADIAN BASIN OF THE ARCTIC-OCEAN - RESULTS FROM THE LARSEN-93 EXPEDITION

Potential temperature (theta) and salinity (S) data obtained along the perimeter of the southern Canadian Basin north of the East Siberian Sea in 1993 aboard the CCGS Henry Larsen show higher temperatures in waters of Atlantic origin than in available climatological data for the Canadian Basin. In particular, a front is observed neat the Mendeleyev Ridge which separates the cooler Atlantic waters of the Canada Basin from the warmer Atlantic waters observed in the Makarov Basin. The front is further characterized by a change in the theta/S slope of Arctic thermocline water, and by thermohaline intrusions (theta and S reversals) within the Atlantic layer. The idea that this warm variety of Atlantic water has come recently from the Eurasian Basin is supported by its higher level of the tracer CFC-11.