Black carbon, which is formed in various combustion processes, is an important climatic factor. It absorbs sunlight and thus warms the surrounding atmosphere. However, not all optical properties of black carbon are fully known. In this project, a new method and a measurement instrument is developed to study the light absorption enhancement of black carbon as a function of particle size. The method is based on cantilever-enhanced photo-acoustic spectroscopy, which has been and will be developed in this project in the Laser Spectroscopy Research Group of the University of Helsinki. Measurements are performed both in the laboratory and in field measurement campaigns. The results obtained can be used to better understand how black carbon contributes to global warming.

2022

2025