Johan Ström Professor
Contact
Name and title: Johan StrömProfessor
Workplace: Department of Environmental Science Länk till annan webbplats.
Visiting address Room X 215Svante Arrheniusväg 8 C, Geohuset
Postal address Institutionen för miljövetenskap106 91 Stockholm
About me
I earned my PhD in Meteorology from Stockholm University in 1993 and became a professor in 2005. My research explores the fascinating life cycle of atmospheric aerosols — tiny airborne particles that affect everything from cloud formation to air quality. These particles play a key role in the Earth’s climate system and, in urban environments, have important implications for human health and environmental sustainability.
From top left corner clockwise:
1) Monitoring pristine air in the Arctic (https://acp.copernicus.org/articles/22/3321/2022/)
2) Monitoring urban air using taxis (https://www.tandfonline.com/doi/full/10.3402/tellusb.v66.23533)
3) Natural and anthropogenic high altitude clouds (https://journals.ametsoc.org/view/journals/atsc/57/4/1520-0469_2000_057_0464_ottoci_2.0.co_2.xml)
4) Near field observations of aircraft exhaust (https://agupubs.onlinelibrary.wiley.com/doi/10.1029/95JD03405)
5) Historic records in snow and ice (https://acp.copernicus.org/articles/14/11447/2014/acp-14-11447-2014.pdf)
Over time, I have supervised students at the secondary school, bachelor’s, master’s, and PhD levels. Currently, my involvement in education focuses primarily on managing the Bachelor’s program in Environmental Science, including the 15-credit thesis course. I am also responsible for coordinating the departments´s two mandatory PhD courses—Research Ethics and Environmental Science—and serve as a member of the Research Education Council.
Clouds and haze interact with the Earth's radiation energy balance and are therefore key components of the climate system. Light-absorbing particles such as black carbon (soot) and desert dust deposited on ice and snow can accelerate glacier melt, intensifying climate change and altering freshwater availability — particularly across regions such as the Himalayan Plateau. Human emissions of gases and particles influence the natural system on a global scale, while emissions near populated areas are also harmful to human health and contribute to many premature deaths.
The aerosol life cycle is a broad and complex scientific topic that encompasses numerous processes across wide spatial and temporal scales. This has taken me to fieldwork in diverse environments — from urban areas to remote regions, from the stratosphere to ice cores, and from the poles to the equator. My strongest scientific motivation lies in curiosity and a persistent ambition to uncover the mechanisms that control key processes in our environment. (Images from a selection of research environments studying the aerosol life cycle).