Presentation given by G. Tsiropoula and I. Kontogiannis at the Splinter Meeting on Synoptic Observations in Göttingen on October 16, 2017.

The meridional flow inside the Sun is a large-scale flow observed on both hemispheres of the Sun. Its structure and variation inside the Sun is of major interest as it transports mass, angular momentum and magnetic flux. Therefore a detailed knowledge is required to understand the magneto-hydrodynamics of the Sun's convection zone and consequently the Sun's magnetic variability. In the past local helioseismology has drawn a detailed picture on this flow in the near-surface layers 15 Mm beneath the solar surface, i.e. in the outer 2% of the Sun. Recently, the helioseismic measurement of this flow throughout the whole convection zone of the Sun has made significant progress by the development of improved helioseismic methods. These reveal that the meridional flow has a possible multi-cellular structure in latitude and depth. Furthermore there are indications that this flow varies during the solar activity cycle. However a final consensus on the structure and temporal evolution of the flow has not been achieved, especially as the signal is weak and affected by noise and systematic effects. In this talk I will review the current status and efforts of helioseismology of the Sun’s meridional flow.

Slides of talk given at L5 consortium meeting in Göttingen on October 17, 2017.

These are the slides of my presentation held at the Solarnet (H2020) Kick-Off Meeting in Brussels, giving an overview on the work package WP8: SPRING.