Researchers reviewed black carbon emission factors from different anthropogenic sources

The review emphasizes the importance of society level emission regulation in black carbon emission mitigation as a clear black carbon emission reduction was observed for road traffic as well as in direct emission measurements of diesel-powered individual vehicles.

The black carbon emissions of gasoline vehicles were observed to be higher for vehicles with direct fuel injection techniques (gasoline direct injection) than for vehicles with port-fueled injection signaling potentially negative trend in gasoline vehicle fleet black carbon emission factors.

For shipping, a clear correlation was seen between the engine size and black carbon emission factors: black carbon emission factors for the largest engines were the lowest. Black carbon emission factors from residential combustion showed large variation indicating that fuel type and quality as well as combustion appliances influenced black carbon emission factors.

Researchers found data gaps in emission factors of large-scale energy production

The largest data gaps were found to be in emission factors of large-scale energy production. Additionally, much more research is required to improve the global coverage of black carbon emission factors.

Moreover, the use of existing data was complicated by different calculation methods for emission factors, different units used in reporting them and by variation of results due to different experimental setups and black carbon measurement techniques.

Black carbon is a significant air pollutant and substantial efforts need to be done in near future to increase the understanding of the sources of black carbon, most efficient mitigation methods as well as its influence on climate, air quality and health. By including accurate black carbon emission factors in emission inventories, climate models and health models, it will be easier to effectively diminish the adverse impacts and subsequent societal costs caused by black carbon emissions.

The study was financially supported by Business Finland BC Footprint project and Academy of Finland Flagship funding Atmosphere and Climate Competence Center (ACCC), Project EFFi and Project BBrCaC. The leading partner was Tampere University supported by the researchers from Finnish Meteorological Institute and Technical Research Center of Finland VTT.

Further information:

Group leader Hilkka Timonen, Finnish Meteorological Institute, Hilkka.Timonen@fmi.fi

Senior Researcher Sanna Saarikoski, Finnish Meteorological Institute, Sanna.Saarikoski@fmi.fi

Professor Topi Rönkkö, Tampere University, Topi.Ronkko@tuni.fi

Scientific article is available on Environmental Research Letters.

Reference: Rönkkö, T., Saarikoski, S., Kuittinen, N., Karjalainen, P., Keskinen, H., Järvinen, A., Mylläri, F., Aakko-Saksa, P. and Timonen, H. (2023). Review of black carbon emission factors from different anthropogenic sources.Environ. Res. Lett. 18 033004.