caused by the interaction of synoptic-scale atmospheric flow

and Greenland, are an important mechanism for forcing

open ocean convection in the south-east Labrador Sea. Here

float data and meteorological reanalysis fields from the

winter of 1996/1997, in combination with a simple mixedlayer

ocean model, are used to show that, although

relatively deep ocean convection did occur during this

winter, the primary forcing mechanism was cold-air

outbreaks from the Labrador coast rather than the smaller

scale reverse tip-jets. During this winter, the North Atlantic

Oscillation (NAO) was in a weak positive phase. Similar

treatments of the winters of 1994/1995 (strong, positive

NAO) and 1995/1996 (strong, negative NAO) suggest that

the result is robust regardless of the state of the NAO.