Characterisation of Black Carbon (BC) mixing state and flux in Beijing using single particle measurements.
Year: 2017
Type: article
Abstract: BC is generated by the incomplete combustion of carbonaceous fuels and it is an important component of fine \nPM2:5. In the atmosphere BC particles have a complex structure and its mixing state has crucial impact on optical \nproperties. Quantifying the sources and emissions of black carbon in urban environments is important and presently \nuncertain, particularly in megacities undergoing rapid growth and change in emissions. During the winter of 2016 \n(10th Nov-10th Dec) the BC was characterised as part of a large joint UK-China field experiment in Beijing. \nThis paper focuses on understanding the mixing state of BC as well as identification and quantification of BC \nsources. We used a combination of a Centrifugal Particle Mass Analyser (CPMA) and a Single Particle Soot \nPhotometer (SP2) to uniquely quantify the morphology independent mass of single refractory BC particles and their \ncoating content. The CPMA allows us to select pre-charged aerosol particles according to their mass to charge ratio \nand the SP2 provides information on the mass of refractory BC through a laser-induced incandescence method. \nFurthermore, another SP2 was used to measure the BC flux at 100m height using the Eddy Covariance method. \nWe have successfully gathered 4 weeks of continuous measurements which include several severe pollution events \nin Beijing. Here we present preliminary results, characterising the distribution of coating mass on BC particles in \nBeijing and linking this to the main sources of BC in the city. We will provide initial estimates of the BC flux \nover a several kilometre footprint. Such analysis will provide important information for the further investigation of \nsource distribution, emission, lifetime and optical properties of BC under complex environments in Beijing.
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Climate action
Open Access status: green
OpenAlex ID: W3089314504