We study the physical properties of aerosol particles in different environments, such as their concentration, size, charge, size distribution and optical properties.

Our goal is to understand processes that modify the atmospheric aerosol population and what affects their ability to act as cloud condensation nuclei or ice nuclei. Our group is also involved in deveopment of instruments and methods to measure especially the smallest aerosol particles.

Atmospheric aerosol particles are tiny solid or liquid particles floating in the air. Their size range from about one nanometer (1·10-9m) to hundreds of micrometers (1·10-4m). Aerosol particles affect the climate by scattering light and forming clouds. They also affect air quality and therefore human health.

Aerosol particles originate from many different sources. They can be emitted from natural sources like desert dust, volcanoes or oceans, or from anthropogenic activities, for example traffic, industry or domestic burning. They can also form in the atmosphere from condensable vapors, like sulphuric acid and organic vapors from the vegetation.


We participate in conducting long-term aerosol measurements at SMEAR-stations and other research infrastructures and take part in data evaluation and analysis. We are running measurements for example in Värriö in eastern Lapland (SMEAR I), Hyytiälä in southern Finland (SMEAR II), Helsinki (SMEAR III), Qvidja farm (south-west Finland) and Cyprus.

We also organize and take part in measurement campaigns all over the world, lasting from weeks up to a year. The campaign measurements are conducted together with other research teams at INAR as well as other collaborators. Additionally, we conduct laboratory experiments and calibrations to characterize our instruments and participate in the devepoment of the instruments and analysis methods, as well as standard-operation-procedures and software.

Ongoing or recent projects