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Conclusion and comments

This study provides evidence that the seasonal decreases in the total ozone column over the West coast of South America originate in the circulation of winds at various elevations in the affected region. This circulation generates one vorticity which pushes air upwards from below the ozone layer, and another vorticity which pushes air down from above, thus compressing the layer and producing a redistribution in its density, which results in the observed ozone decrease over the region in question. The reason this occurs mainly in summer has to do with the wind patters that create the vorticities which in turn account for the ozone decreases. It has been noted that the minimum ozone densities occur over the Andes mountain peaks, leading some authors to claim them as the cause of a thinner ozone layer [4]. It is possible that they contribute to the depletion, but this does not explain the fact that the phenomenon occurs mainly in the southern hemisphere summer.