Climate sensitivity to the lower stratospheric ozone variations

The strong sensitivity of the Earth's radiation balance to variations in the lower stratospheric ozone—reported previously—is analysed here by the use of non-linear statistical methods. Our non-linear model of the land air temperature (T)—driven by the measured Arosa total ozone (TOZ)—explains 75% of total variability of Earth's T variations during the period 1926–2011. We have analysed also the factors which could influence the TOZ variability and found that the strongest impact belongs to the multi-decadal variations of galactic cosmic rays. Constructing a statistical model of the ozone variability, we have been able to predict the tendency in the land air T evolution till the end of the current decade. Results show that Earth is facing a weak cooling of the surface T by 0.05–0.25 K (depending on the ozone model) until the end of the current solar cycle. A new mechanism for O3 influence on climate is proposed.

► An increased climate sensitivity to ozone variations is analysed. ► O3 driven model of surface T explains the greatest part of its variability. ► Impact of different factors on lower stratospheric O3 variability is estimated. ► Galactic cosmic rays have a greatest influence on O3. ► Mechanism for ozone influence on climate is described.