Ozone‐related trends in solar UV‐B series

It is now well established that stratospheric ozone has become depleted on a global scale, with downward trends of several percent per decade in populated mid-latitude regions, but evidence of the expected parallel increases in solar UV-B radiation has remained elusive to date; if anything, past studies have actually reported decreases. The broken, ten-year record of Robertson-Berger meter UV-B measurements for a clean-atmosphere, mid-latitude site in the Southern Hemisphere that we analyse here is incapable of independently confirming a long-term upward trend, but it does provide specific evidence in support of the trend hypothesis. In particular, there is a very strong relationship between daily clear-sky UV-B and parallel ozone measurements, with correlation coefficients in the range of 0.84 to 0.95, and the trends and variations in ozone are very well matched by corresponding opposite trends and variations in UV-B.