In late January and early February 1983, observations made by the Stratospheric Aerosol Measurement (SAM II) satellite system showed that aerosol extinction profiles measured within the northern polar vortex differed significantly above 18 km from those measured outside the vortex. Values of the calculated optical depths above 18 km for February 1, 1983, are lower by approximately one order of magnitude within the polar vortex than those outside. Similar differences were found in the aerosol backscattering profiles obtained using an airborne lidar system when crossing the polar vortex. Since potential vorticity at a constant altitude is not conserved across the polar vortex, horizontal adiabatic transport does not occur.