The Sun is the main energy source for the Earth's atmosphere. The main manifestations of external forcing from space to the atmosphere are in variations in solar parameters such as the solar irradiance (including solar UV) and solar particle fluxes. These parameters can induce changes in the atmosphere both at local and global scales, and can influence over a large range of altitudes up to the thermosphere. Some of these changes have the potential to affect the troposphere through atmospheric coupling processes, particularly through the stratosphere-troposphere connection, and thus have the potential to influence weather and climate.
The field of space weather, that is the change in the environment between the Sun and the Earth, has seen a rapid increase in research activity in recent years and in associated large scientific advances. The weather and climate community can benefit from this via better representation of space weather effects and their associated impacts on the atmosphere.

The overarching goal of this session is to connect communities within the Sun-to-Earth system and in so doing promote Sun-to-Earth system science, products and services. The aim is to review the state-of-the-art and to identify possible interrelationships between Earth and the Sun and space weather by assessing the level of coupling in the relevant physical systems and processes.

Contributions from the following topics (but not exclusively) are welcome:
• Upper atmospheric dynamical variability and coupling between atmospheric layers e.g. thermosphere-ionosphere coupling
• Solar irradiance and energetic particle impacts on the atmosphere
• Solar variations and stratosphere-troposphere coupling
• Solar influence on climate variability
• Solar irradiance (spectral and total irradiance) variations
• Sun-Earth and Sun-planet interrelationships (of relevance to e.g. spacecraft for planetary exploration which require planet meteorology forecasts)
• Space weather observation, forecasting products and services