BBrCaC

The contributions of black and brown carbon (BC and BrC) to the radiative forcing of climate will be estimated in Finland and in a wider boreal context. The contributions of BC and BrC to light absorption in the uv-vis wavelength range in urban and background aerosols, aerosol emissions from different fuels, and snow will be measured. Aerosols will be measured in Helsinki and Lapland and in aging-chamber experiments in Kuopio. Long-term (60 years) filter samples, snow collected in Finnish Lapland, Svalbard, Siberia and the Alps and a 300-year time series of ice from Svalbard will be analyzed for BC and BrC concentrations and absorption spectra. Fossil fuel and biomass burning contributions will be estimated by carbon isotope analyses. Emission inventories will be updated to include BrC by using measured BC and BrC emission factors and used for updating emission scenarios and estimating the radiative forcing of BC and BrC in selected scenarios for the period 2020-2100.

2021

2025