Time-asymmetric fluctuations in the atmosphere: daily mean temperatures and total-column ozone

Fluctuations breaking time-reversal symmetry are common attributes of dissipative systems operating far from equilibrium. Recent developments in non-equilibrium statistical physics represent a significant step towards an understanding of how time-reversible microscopic laws can yield to inherent irreversibility on meso-or macroscopic scales. Most of the theoretical conclusions consider quantities (e. g. entropy production) that are difficult to obtain with an appropriate accuracy in real systems. Probably less-complicated measures, such as the simple step-number ratio used in this work, can also help to characterize time-asymmetric fluctuations. In the first part, we give a short summary of recent results on asymmetric daily mean temperature changes. The second part discusses total-column ozone fluctuations, where statistically significant asymmetries are also detected. A detailed correlation analysis of ozone signals and high-altitude temperature records supports the strong coupling between tropospheric dynamics and stratospheric processes on synoptic time scales.