Modelling the formation of atmospheric aerosol particles

Ville Loukonen & computational aerosol physics group University of Helsinki/Department of Physics/Division of Atmospheric Sciences

It is commonly known that aerosol particles affect visibility and can potentially cause adverse health effects. Recently, there has been a lot of discussion about the role of aerosol particles in the climate change: how these small particles directly interact with electromagnetic radiation and indirectly affect the Earth's albedo by taking part in cloud formation processes. Furthermore, not only are the particles emitted into the atmosphere in particulate phase important: according to some studies 20-80% of all atmospheric aerosol particles form in the atmosphere from gaseous precursors.

However, aerosol particle formation mechanisms are not yet properly understood. This is due to the challenges in both experimental and theoretical research.

In this talk I will discuss theoretical challenges related to mesoscopic modelling of the phenomenon and especially concentrate on the importance of accurate molecular-level modelling of the initial steps of aerosol particle formation.