NAO-induced spatial variations of total ozone column over Europe at near-synoptic time scale

The variations of total ozone column over Europe at the multiyear time scale have earlier been characterised by the changes in the phase of North Atlantic Oscillation. Spatial patterns over Europe in total ozone column response to weather pattern changes associated with the North Atlantic Oscillation are investigated here using the cross-wavelet transform. The average cross-wavelet powers and local relative phases are calculated. It is shown that near a centre of action associated with the NAO the changes of total ozone column are maximal and become apparent immediately after the changes in the weather pattern.

► It can be registered positive correlations between daily NAO index and Arosa TOC.
► The cross-wavelet transform is useful to conclude a coherency between time series.
► Local time lags of TOC variability depend on the distance to NAO’s centre of action.
► Signs of pressure anomaly in the centre of action determine cross-wavelet power.