As every year, members of the ICOS-CH consortium are contributing to this year's Swiss Geoscience Meeting. The session "Atmospheric Composition and Biosphere-Atmosphere Interactions" (Session 17) is closely linked to ICOS and co-chaired by Martin Steinbacher (Empa) and Mana Gharun (ETH Zurich). Several ICOS-CH member are involved in posters and talks. Although originally planned to be held in Geneva, this year's Swiss Geoscience Meeting is again online due to the pandemic situation.