Observations of Photospheric Dynamics and Magnetic Fields: From Large-Scale to Small-Scale Flows

International audienceThis paper reviews solar flows and magnetic fields observed at the photospheric level. We first present the context in which these observations are performed. We describe the various temporal and spatial scales involved, and the coupling between them. Then we present small-scale flows, mainly supergranulation and flows around active regions. Flows at the global scale are then reviewed, again with emphasis on the flows, i.e. differential rotation, torsional oscillation and meridional circulation. In both small- and global-scale we discuss the coupling between flow fields and magnetic field and give an overview of observational techniques. Finally, the possible connection between studies of solar activity and stellar activity is briefly discussed

Observing Dynamos in Cool Stars

The main aim of this paper is to introduce the most important observables that help us to investigate stellar dynamos and compare those to the modeling results. We give an overview of the available observational methods and data processing techniques that are suitable for such purposes, with touching upon examples of inadequate interpretations as well. Stellar observations are compared to the solar data in such a way, which ensures that the measurements are comparable in dimension, wavelength, and timescale. A brief outlook is given to the future plans and possibilities. A thorough review of this topic was published nearly a decade ago (Berdyugina 2005), now we focus on the experience that have been gathered since that time.Comment: 47 pages, accepted for publication in Space Science Review