On the origin of magnetic fields in the quiet photosphere

We consider the possibility that a substantial fraction of the magnetic field in the quiet photosphere is generated locally by dynamo action associated with the granular and supergranular flows. The argument is based on recent advances in the theory of fast dynamos and is supported by large-scale numerical simulations that show that thermally driven turbulent convection can indeed be an efficient source of small-scale, highly intermittent magnetic fields. Some aspects of the resulting magnetic field, such as its strength and degree of intermittency, are discussed.