This paper by Drews et al. reports model simulations of the effect of the 11-year solar cycle on the atmospheric circulation and hence on year-to-year variations in weather patterns, . The physics of the effect of the solar cycle is complex, but one important mechanism is believed to be via the variation in short-wave radiation, which perturbs the ozone distribution in the upper stratosphere. The key development in this study is a good model representation of chemistry, radiation and dynamics and their interactions to enable the dynamical feedback processes, which potentially communicate the direct physical effects of the solar cycle to the lower part of the atmosphere, to be adequately simulated. An important aspect of the paper is that the authors exploit an ensemble of simulations that make it possible to distinguish a signal due to solar-cycle effects from natural weather variability. The results convincingly show a solar cycle effect, over the North Atlantic in particular, where variations in the circulation have important implications for the weather experienced in Europe. This is particularly the case in the current period (since 1950 or so) when the 11-year solar variation is strong relative to the entire historical record (starting in about 1850). The results of this paper suggest that including solar cycle effects in models used for decadal climate predictions can provide worthwhile improvements in the skill of such predictions.
This paper by Drews et al. reports model simulations of the effect of the 11-year solar cycle on...
Solar irradiance varies with a period of approximately 11 years. Using a unique large chemistry–climate model dataset, we investigate the solar surface signal in the North Atlantic and European region and find that it changes over time, depending on the strength of the solar cycle. For the first time, we estimate the potential predictability associated with including realistic solar forcing in a model. These results may improve seasonal to decadal predictions of European climate.
Solar irradiance varies with a period of approximately 11 years. Using a unique large...