Changes in Column Ozone Correlated with the Stratospheric EP Flux

抄録

Variability in planetary wave forcing from the troposphere to the stratosphere is reflected in changes in ozone transport, due to fluctuations in the stratospheric Brewer-Dobson circulation and eddy mixing. This work examines the space-time patterns of correlations between column ozone tendency and planetary wave Eliassen-Palm (EP) flux into the lower stratosphere, using monthly mean data for 1979-2000. Strong correlations are found during winter-spring in both hemispheres, with out-of-phase ozone changes between the tropics and middle-high latitudes. Springtime polar ozone is strongly influenced by wave forcing in both the Arctic and Antarctic. The ozone tendency-wave forcing correlations are combined with observed variations in EP flux to estimate the dynamic contribution to decadal-scale NH ozone trends. These calculations suggest that interannual changes in EP flux contribute∼20-30% of the observed trends in column ozone over 35-60°N during the past two decades.