Abstract:
Over the past five decades, measurements of solar irradiance and magnetic fields have become vital for understanding solar activity and variability and its effects on Earth’s system and in particular its climate. Recent reconstruction of historical solar data (such as sunspot counts and Ca II K observations) as well as advances with measurements and analyses of cosmogenic isotopes (¹⁴C, ¹⁰Be), have greatly improved long-term reconstructions of solar variability. New insights from state-of-the-art missions alongside advanced MHD simulations, are deepening our knowledge of solar magnetic mechanisms. At the same time, a wealth of recent stellar observations allows comparative studies of solar analogs, which place the Sun’s variability in a broader stellar context and help to better understand Sun-like Stars. This IAU Focus Meeting in Rome aims to unite experts across disciplines, solar and stellar physics, climate science, space weather, and data preservation, to connect historical foundations with future directions.
Key Topics:
- Proxies of long-term solar magnetic activity, in particular advances with sunspot records, Ca II K observations, as well as ¹⁴C and ¹⁰Be records
- Modern observations as a key to understanding solar/stellar magnetism and variability (irradiance, magnetic field emergence and evolution, solar imagery)
- Solar and stellar dynamos
- Recent advances in solar irradiance modeling
- Stellar comparisons: using solar models to explain variability of Sun-like stars
- The impacts of solar and stellar variability on planetary environments, especially Earth's climate, as well as the implications of extreme eruptive events