Intercomparison of ATMOS, SAGE II, and ER-2 observations in Arctic vortex and extra-vortex air masses during spring 1993

We have compared measured abundances of NOy,03, H20 , CH4, HC1, and N20 from ATMOS and aerosol fromSAGE II from inside and outside the Arctic vortex with in situobservations from the SPADE aircraft campaign in April/May1993. When the distinction between vortex and extra-vortexair is taken into account, SPADE measurements ofNOy, 0 3,H20 ,CH4, HC1, and aerosol abundances, correlated with [N 20],demonstrate excellent agreement with ATMOS and SAGE IIdata. Observations of low [HC1] and high [C1NO 3] inside thevortex by ATMOS and low [HC1] in vortex fragments byALIAS suggest that vortex-influenced air masses maintainedunusually high levels of [C1NO 3] throughout spring 1993.