Solar Impact on Climate: Modeling the Coupling Between the Middle and the Lower Atmosphere

Solar variability influences the earth's atmosphere on different time scales. In particular, the impact of the 11-year solar cycle is of interest as it provides the major contribution to natural climate variability. Observations show clear 11-year variations in meteorological variables such as temperature or geopotential height from the upper atmosphere down to the troposphere and the earth's surface. In this paper the mechanisms will be discussed which are assumed to be responsible for the downward transfer of the solar signal within the atmosphere. These involve radiative, dynamical and chemical processes which have been studied in detail in model simulations and will be presented here