The influence of cosmic rays on the size of the Antarctic Ozone Hole

TL;DR

This study investigates the connection between galactic cosmic rays and the Antarctic ozone hole size, revealing time-dependent correlations and anti-correlations that suggest multiple modulation processes affecting ozone depletion.

Contribution

It provides evidence of a link between cosmic ray flux variations and ozone hole size, analyzing their relationship over time using wavelet spectral analysis.

Findings

Identified 3- and 5-year common signals between GCR and ozone hole size.

Found time-dependent anti-correlation between GCR and ozone hole size.

Detected a 1.7-year correlation during specific periods.

Abstract

The Antarctic region in which severe ozone depletion has taken place is known as the ozone hole. This region has two basic indicators: the area, where the ozone abundance is low (size), and the quantity of ozone mass deficit (depth). The energetic particles that penetrate deeply into the atmosphere and galactic cosmic rays (GCR) modify the ozone abundance in the stratosphere. With this research project, we are looking for evidence of a connection between variations in the cosmic ray flux and variations in the size of the ozone hole. In addition, we are looking for signs of the kind of processes that physically connect GCR fluxes with variations in the stratospheric ozone hole size (OHS) in the Antarctic region. With this goal in mind, we also analyze here the atmospheric temperature (AT) anomalies, which have often been linked with such variations. Using Morlet's wavelet spectral analysis to compute the coherence between two time series, we found that during the analyzed period (1982-2005), there existed a common signal of around 3 and 5 years between the OHS and GCR time series, during September and November, respectively. In both cases, the relationship showed a time-dependent anti-correlation between the two series. On the other hand, for October the analysis showed a time-dependent correlation that occurs around 1.7 years. These results seem to indicate that there exist at least two kinds of modulation processes of GCR fluxes on the OHS that work simultaneously but that change their relative relevance along the timeline.