Correlation between Cosmic Rays and Ozone Depletion

This Letter reports reliable satellite data in the period of 1980–2007 covering two full 11-yr cosmic ray (CR) cycles, clearly showing the correlation between CRs and ozone depletion, especially the polar ozone loss (hole) over Antarctica. The results provide strong evidence of the physical mechanism that the CR-driven electron-induced reaction of halogenated molecules plays the dominant role in causing the ozone hole. Moreover, this mechanism predicts one of the severest ozone losses in 2008–2009 and probably another large hole around 2019–2020, according to the 11-yr CR cycle.

Figure 1

Percentage variations of CR intensity and annual mean total ozone with latitudes 0–60° S during the period of 1980–2007. The CR data (solid line) were averaged from 3 station measurements (McMurdo, Thule, and Newark) of the Bartol Research Institute [27], while ozone data (solid circles + line) were obtained from NASA TOMS/OMI satellite datasets [28]. The ozone data were relative to the value at 1992.

Figure 2

Percentage variations of CR intensity and monthly mean total ozone in October Antarctic with latitudes of 60–90° S during the period of 1990–2007. The CR data are the same as in Fig. 1, while ${\mathrm{O}}_3$ data (solid circles + line) were obtained from NASA TOMS/OMI satellite datasets with a nominal uncertainty of 1% [28], relative to the value at 1992. The 2002 ${\mathrm{O}}_3$ data point is multiplied by a factor of 0.75 to fit in the plot; the solid line passing through the data points is a smoothed curve to aid the eyes. The total ${\mathrm{O}}_3$ data for October 2008 (upper triangle) is a predicted value (see text).

Figure 3

Percentage variations of CR flux (solid line) and annual mean total ${\mathrm{O}}_3$ (data points + lines) measured at two Antarctic stations, Faraday/Vernadsky (65°15′S, 64°16′W) and Halley (75°35′S, 26°36′W), during the period of 1990–2007. The CR data are the same as Fig. 1, while ${\mathrm{O}}_3$ data (solid circles from Faraday station; solid squares from Halley) were obtained from the British Antarctic Survey [29], relative to the value at 1992. The data point at Halley in 2002 is multiplied by a factor of 0.7 to fit in the plot.

Figure 4

Percentage variation of mean total ozone vs CR intensity with all the data from Figs. 1, 2, 3: solid circles for annual ${\mathrm{O}}_3$ data with latitudes 0–60° S, upper triangles for October ${\mathrm{O}}_3$ with latitudes 60–90° S, down triangles and diamonds for annual ${\mathrm{O}}_3$ at Halley and Faraday/Vernadsky, respectively. To plot all these data together, the October and annual ${\mathrm{O}}_3$ data for the polar region were reduced by factors of 5 and 2.5, respectively. The solid line is the best fit to the data, giving a linear equation (see text).