LAC - Laboratory of Atmospheric Chemistry
The Laboratory of Atmospheric Chemistry (LAC), established 1 January 2000, is a laboratory of the Energy and Environment Research Division (ENE) at the Paul Scherrer Institute.
Our laboratory comprises three interacting groups that operate a large variety of facilities and instruments in the lab and in the field.
In contrast to nitrogen oxides, modern gasoline cars emit much more cancerogenic primary soot (black carbon + primary organic aerosol) and lead to more toxic secondary organic aerosol than modern diesel vehicles.
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.
Aerosols, suspended fine liquid or solid particles in the air we breathe, play a central role in many environmental processes through their influence on climate, the hydrological cycle, and their adverse effects on human health. While the mechanisms by which aerosol particles affect our health remain uncertain, the atmospheric oxidation of organic vapors has been shown to be related to the formation of oxygenated organic matter with high oxidative potential, the so-called reactive oxygen species (ROS).
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.