1Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China
2State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
3Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
4Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
5Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
1Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China
2State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
3Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
4Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
5Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
Received: 25 Apr 2022 – Discussion started: 20 May 2022
Abstract. Black carbon (BC) is an important atmospheric component with strong light absorption. Many attempts have been made to measure BC mass size distribution (BCMSD) for its significant impact on climate and public health. Larger-coverage BCMSD, ranging from upper submicron to larger than 1 μm, contributes to substantial proportion of BC absorption. However, current time resolution of larger-coverage BCMSD measurement was limited to 1 day, which was insufficient to characterize variation of larger-coverage BCMSD. In this study, a new method to determine BCMSD was proposed from size-resolved absorption coefficient measured by an aerodynamic aerosol classifier in tandem with an aethalometer. The proposed method could measure larger-coverage BCMSD with time resolution as high as 1 hour and was validated by comparing the measurement results with that measured by a differential mobility analyzer in tandem with a single particle soot photometer (DMA – SP2) for particle size larger than 300 nm during a field measurement in Yangtze River Delta. Bulk BC mass concentration (mBC,bulk) by DMA – SP2 was underestimated by 33 % compared to that by this method because of the limited size range of measurement for DMA – SP2. Uncertainty analysis of this method was performed with respect to mass absorption cross-section (MAC), transfer function inversion, number fraction of BC-containing particle and instrumental noise. The results indicated that MAC was the main uncertainty source, leading to mBC,bulk varied from – 20 % to 28 %. With the advanatage of wide size coverage up to 1.5 μm, high time resolution, easy operation and low cost, this method is expected to have wide applications in field measurement for better estimating radiative properties and climate effects of BC.
A new method to determine black carbon mass size distribution (BCMSD) was proposed using size-resolved absorption coefficient measured by an aerodynamic aerosol classifer in tandem with an aethaelometer. This new method fills the gap in the high-time-resolution measurement of BCMSD ranging from upper submicron to larger than 1 micron. This method can be applied to field measurement of BCMSD extensively for better understanding the BC aging and better estimating BC climate effect.
A new method to determine black carbon mass size distribution (BCMSD) was proposed using...