Clouds consist of tiny droplets. These droplets form when water condenses around so-called aerosols – small particles in the atmosphere. To understand how in turn aerosols come into existence scientists have now created a comprehensive computer model simulation based on profound experimental data. This simulation revealed that in addition to sulphuric acid, two other substances are crucially involved in the formation of aerosols: organic compounds and ammonia. These results have now been published in the renowned journal Science.
Researchers have shown how fine particles are formed from natural substances in the atmosphere. These findings will improve our knowledge about clouds in the pre-industrial era and thus will contribute to a more accurate understanding of both the past and future evolution of our climate.
29. June 2015Media Releases Environment Energy and Environment
For years, studies have proved that fine dust from petrol engines can damage our health. Modern engine technology does not help, either, as researchers from the University of Bern and the Paul Scherrer Institute (PSI) reveal.
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17. September 2014Media Releases Environment Energy and Environment
The causes of China's record level fine particulate pollution in winter 2013
At the beginning of 2013 a greyish-brown blanket of smog lay over large areas of China for several months. The fine particle pollution was higher by 1 to 2 orders of magnitude than the levels normally measured in Western Europe and the United States. An international team of researchers under the lead of the Paul Scherrer Institute PSI and the Institute of Earth Environment, Chinese Academy of the Sciences revealed the causes of the
airpocalypse. The study published in the journal Nature also describes what steps are to be taken to prevent an environmental crisis of this kind in the future. See also the news report of the Chinese TV (in Chinese) on 2014-09-18:
13. May 2014Media Releases Energy and Environment Environment
In some towns small mopeds cause more air pollution than cars
Not cars or trucks, but mopeds with their two-stroke engines are the main source of fine particles and other air contaminants in many towns in Asia, Africa and southern Europe. This is revealed by the study of an international research team headed up by researchers at the Paul Scherrer Institute PSI. The reasons for the high emissions are the combustion properties in two-stroke engines and the overly lenient emission requirements for small two-wheelers. The study findings are to be published on 13 May 2014 in the journal Nature Communications. News report on Swiss TV (in German)
17. December 2013Media Releases Energy and Environment Environment
PSI-researcher Martin Gysel receives prestigious European funding (ERC Consolidator Grant) for his studies on the role of soot in cloud formation and global warming.
6. October 2013Media Releases Energy and Environment Environment
Clouds consist of cloud droplets that are formed from tiny particles floating in the atmosphere. How these particles develop, however, largely remains a mystery. The formation of particles from amines and sulphuric acid has now been described for the first time – a milestone in atmospheric research.
19. April 2010Media Releases Energy and Environment Environment
Data of the Paul Scherrer Institute from the High-Alpine Research Station Jungfraujoch yield important information.
The eruption of the volcano Eyjafjallajokull in Iceland has stalled flight traffic in large parts of Europe. Decision makers had to base their decisions mainly on model calculations for the volcanic plume dispersion. How dangerous is this volcanic ash layer for planes?
18. January 2010Media Releases Environment Energy and Environment
Up to the present time, the nucleation or new formation of particles in the atmosphere has been a great enigma. Until recently, research was based on the assumption that sulphuric acid played the central role in particle formation. However, laboratory experiments and field tests have consistently provided conflicting results. In the lab, considerably higher concentrations of sulphuric acid are required for nucleation to take place than in the atmosphere itself. Now scientists from the Paul Scherrer Institute (PSI) have found out the cause for these conflicting results from their smog chamber. These findings will advance climate research to a significant degree.
10. December 2009Media Releases Environment Energy and Environment
Researchers from the Paul Scherrer Institute, the University of Colorado and 29 other research institutions in various countries have investigated the composition of the organic constituents of the fine particulates found in various regions of the world, and have identified the original substances from which they are formed in each case. For the first time ever, this has enabled them to explain the role played by the individual components of emissions in the development of fine particulates.
25 Aug 2011
CCN formation mechanism in lower troposphere needs revision
Role of sulphuric acid, ammonia and galactic cosmic rays in atmospheric aerosol nucleation
Kirkby et al.,
Contact: Prof. Dr. Urs Baltensperger, Telephone: +41 56 310 24 08, Email: email@example.com,
Media Release: Klimaforschung am Teilchenbeschleuniger: Beschreibung der Aerosolneubildung muss revidiert werden (in German only)