Bibliotek i Västmanland

The report use ozone measurement data retrieved in the Arctic with balloon borne ozone sondes for the last 20-30 years. Four stations with the best data series have been selected. Using a Monte Carlo method the yearly period is subtracted from the data and the remains, the anomalies, are correlated towards the area of the Polar Front, the temperature rise of the Nortern Hemisphere and the North Atlantic Oscillation (NAO) and towards one another. It was found that the NAO correlates negatively with ozone anomalies for all four stations albeit the correlations are weak. Besides, the polar front area correlates weakly positive with the ozone anomalies for three out of the four stations. These results, together with the observation that the ozone-anomalies have a brief decorrelation time, indicate that most of the variability in the anomalies should be found in local conditions.