Ilona Riipinen

Head of unit
Room: X227
Phone: +46 8 674 7284
Mobile: +46 73 585 9251

What I do

The air we breathe does not consist of gas molecules only: each cubic centimetre of atmospheric air typically contains thousands of small aerosol particles. These liquid or solid airborne particles originate from both natural sources (e.g. forests, oceans, deserts) as well as human activities (e.g. combustion processes, traffic), and their diameters span from nanometres to hundreds of micrometres.

Atmospheric aerosol particles play an important role in defining the environments we live in. When inhaled, many particles are harmful to human health. Atmospheric particles also decrease visibility and damage buildings and landmarks when deposited on their surfaces. On global scale, aerosols regulate the Earth’s energy balance and therefore the climate. In current climate models aerosols are still poorly represented: the Intergovernmental Panel on Climate Change recognizes aerosols as the largest individual source of uncertainty in calculations of the Earth’s radiative forcing.

My research focuses on understanding the sources, sinks and evolution of atmospheric aerosol particles and their interactions with clouds, climate and human health. My current focus is largely on the interactions between aerosol particles and the atmospheric gas phase, in particular the formation and effects of atmospheric organic aerosol and thus the feedback between ecosystems, human activities and climate.

Together with my colleagues, I work mainly with atmospheric computational models representing the processes governing the evolution and impacts of atmospheric aerosol populations. We model the evolution of atmospheric aerosol from the molecular to the global scale, with a tight connection to experimental data from both laboratory and field studies. The underlying philosophy is that to correctly upscale the molecular level processes to global scale, the scientists working on the fundamental theory need to be brought together with the scientists working on the highly simplified aerosol descriptions in regional and global atmospheric models.


Alumni (PhD students and post-docs I have adviced)

Dr. Erica Trump (Carnegie Mellon University, now at OSIsoft)
Dr. Taina Yli-Juuti (University of Helsinki, now at University of Eastern Finland)
Dr. Benjamin Murphy (Stockholm University, now at US Environmental Protection Agency)
Dr. Silja Häme (formerly Häkkinen) (University of Helsinki, now at University of Helsinki)
Dr. Juan Camilo Acosta Navarro (Stockholm University, now at Barcelona Supercomputing Center)
Dr. Elham Baranizadeh  (University of Eastern Finland, now at University of California Riverside)
Dr. Jan Julin  (Stockholm University, now at Lund University)
Dr. Lars Ahlm  (Stockholm University, now at the Department of Meteorology at Stockholm University)
Dr. Maryam Dalirian  (Stockholm University)

Major part of my work is funded by the European Research Council starting grant ATMOGAIN (grant No 278277-ATMOGAIN), Vetenskapsrådet, Formas and the Wallenberg Academy Fellowship program.

Latest scientific papers

Effect of bisulfate, ammonia, and ammonium on the clustering of organic acids and sulfuric acid

Myllys, N.; Olenius, T.; Kurtén, T.; Vehkamäki, H.; Riipinen, I.; Elm, J.;
2017 | J Phys Chem A | 121 (4812-4824)

New particle formation from sulfuric acid and amines: Comparison of monomethylamine, dimethylamine, and trimethylamine

Olenius, T.; Halonen, R.; Kurtén, T.; Henschel, H.; Kupiainen-Määttä, O.; Ortega, I. K.; Jen, C. N.; Vehkamäki, H.; Riipinen, I.;
2017 | J. Geophys. Res.-Atmos. | 122 (7103-7118)

Revising the hygroscopicity of inorganic sea salt particles

Zieger, P.; Väisänen, O.; Corbin, J.; Partridge, D. G.; Bastelberger, S.; Mousavi-Fard, M.; Rosati, B.; Gysel, M.; Krieger, U.; Leck, C.; Nenes, A.; Riipinen, I.; Virtanen, A.; Salter, M.
2017 | Nat. Commun. | 8 (15883)

Measured Saturation Vapor Pressures of Phenolic and Nitro-aromatic Compounds

Bannan, TJ; Booth, AM; Jones, BT; O'Meara, S; Barley, MH; Riipinen, I; Percival, CJ; Topping, D
2017 | Environ. Sci. Technol. | 51 (7) (3922-3928)

Estimates of the organic aerosol volatility in a boreal forest using two independent methods

Hong, J; Aijala, M; Hame, SAK; Hao, LQ; Duplissy, J; Heikkinen, LM; Nie, W; Mikkila, J; Kulmala, M; Prisle, NL; Virtanen, A; Ehn, M; Paasonen, P; Worsnop, DR; Riipinen, I; Petaja, T; Kerminen, VM
2017 | Atmos. Chem. Phys. | 17 (6) (4387-4399)

All publications

Atmospheric Science

The life cycle and impact of tiny atmospheric particles known as aerosols – both indoors as well as outdoors.