In a new Journal of Climate study, D.J. Ivy and co-authors examine changes in Arctic climate since 1979, focusing on the decadal scale. They show that dynamically quiescent years, with no major sudden stratospheric warmings, are marked by a strengthening of the Arctic polar vortex over the past 30 years. Associated changes, such as decreases in temperatures and ozone, propagate downwards into the lowermost Arctic stratosphere during late winter and early spring. This strengthening of the Arctic vortex appears to occur at higher altitudes than in the Antarctic and does not propagate as low into the troposphere, rather the signal remains confined to the uppermost troposphere. The full abstract can be found here.