What are your research topics?
I study chemical reactions occurring in the atmosphere. Such reactions determine, for example, how various emissions generated by humans or forests ultimately affect air composition and, among other things, the amount of aerosols in the air.
Where and how does the topic of your research have an impact?
Aerosols, or fine particles floating in the air, affect human health, the formation of clouds, and as a consequence, the climate. Mitigating climate change and preventing air pollution both require reductions in emissions, but a much greater benefit can be gained by aiming these reductions precisely at the right targets and compounds. At their worst, certain emission reductions can even worsen urban air quality.
What is particularly inspiring in your field right now?
In recent years, instrument development has progressed rapidly, and we are now finally able to carry out sufficiently accurate measurements of several trace gases. This way, we have also learned a lot in recent years, being able to verify or overturn several old assumptions pertaining to atmospheric chemistry. This trend is rapid and will continue.
Mikael Ehn is the Professor of Atmospheric Physical Chemistry at the Faculty of Science.