Solar Variability of Possible Relevance for Planetary Climates

The global variability of the Sun of relevance for planetary climates has been directly measured for the past few decades. For longer stretches of time models are required. Semi-empirical models can now accurately reproduce the measured records of solar total and spectral irradiance, as well as of the magnetic flux. They can also provide reconstructions of these quantities on longer time scales. Here a summary is given of some of the modelling efforts and of the results achieved so far.