Towards Long-Term Solar Irradiance Modelling:Network Contrasts from Magneto-ConvectionSimulations

摘要

Solar irradiance changes on a wide range of time scales and is a key driver of the Earth'sclimate where secular variability in particular is relevant. This is, however, not well understood andour knowledge relies on reconstructions based on sunspot numbers and similar proxies. The prime candidate to produce secular variability is a change in the surface coverage of small-scale magnetic elements. Direct observational determination of the flux emitted by these magneticelements is difficult, especially as information covering a large spectral range is needed. Here wepresent a theoretical approach to this problem using intensity calculations from 3-D simulations ofsolar magneto-convection and compare these with the intensity calculations used in the successfulsemi-empirical SATIRE models at disk centre. Eventually, such a comparison should lead to theremoval of the last free parameter from SATIRE-based irradiance reconstruction.