Professor Bäck’s research centres on the exchange of energy, water, and trace gases between boreal forests and the atmosphere, with particular emphasis on biogenic volatile organic compound (BVOC) emissions, aerosol formation, and the links between ecosystem physiology, climate, and air quality. Through sustained leadership of the SMEAR II measurement network in Hyytiälä and participation in European research infrastructures including eLTER and AnaEE, she has advanced understanding of climate-driven changes in organic aerosol and cloud condensation nuclei, identified previously unaccounted volatile emissions from boreal evergreen foliage, and demonstrated that Pinus sylvestris can serve as a source of methane and nitrous oxide in boreal upland forests. Her work has also contributed to the design of global-change observation networks and to direct observations of atmospheric aerosol nucleation. She has authored 108 peer-reviewed publications, with an h-index of 27 and approximately 3,000 citations. Her scientific contributions have extended into environmental policy and assessment through service on the Finnish Nature Panel (2019–2023), leadership of the European Academies’ Science Advisory Council (EASAC) assessment of the multifunctionality and sustainability of European Union forests, and leadership roles in the Gordon Research Conference on Biogenic Volatiles and Atmosphere and the IPBES–IPCC nexus on biodiversity and climate change. Her representative publications in Science, Scientific Reports, Atmospheric Chemistry and Physics, and Biogeosciences reflect a sustained contribution to understanding forest–atmosphere processes and their implications for climate change, air quality, and sustainable ecosystem management.