AIRBORNE SURVEYS OF THE ATMOSPHERIC BOUNDARY-LAYER ABOVE THE MARGINALICE-ZONE ON THE NEWFOUNDLAND SHELF

Airborne measurements in the atmospheric boundary layer (ABL) above th e marginal ice zone (MIZ) on the Newfoundland Shelf reveal strong late ral variations in mean wind, temperature and the vertical fluxes of he at and momentum under conditions of cold, off-ice wind. Flux measureme nts in (and near) the surface layer indicate that the neutral 10-m dra g coefficient depends on ice concentration, ranging from 2 x 10(-3) at 10% coverage to 5 x 10(-3) at 90%. Furthermore, cross-ice-edge transe cts consistently show increasing wind speed, temperature and heat flux in the off-ice direction, but the momentum flux may either increase o r decrease, depending on the relative importance of surface buoyancy f lux and roughness. For the conditions encountered in this experiment, it appears surface wave maturity does not have a significant influence on the drag coefficient in fetch-limited regimes near the ice edge.