10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Metrology for Light Absorption by Atmospheric Aerosols: The EMPIR Black Carbon Project
Eija Asmi, Joel Corbin, Volker Ebert, Konstantinos Eleftheriadis, François Gaie-Levrel, Martin Gysel, Thomas Müller, Andreas Nowak, Konstantina Vasilatou, Ernest Weingartner, PAUL QUINCEY, NPL
Abstract Number: 793 Working Group: Carbonaceous Aerosol
Abstract Black carbon (BC) is widely recognized as the foremost particulate absorber of solar radiation in the atmosphere and has been associated with the detrimental health effects of air pollution. To monitor BC concentrations, the atmospheric-science community has developed an array of technologies based on light absorption measurements. These absorption measurements are typically reported as mass concentrations of Equivalent Black Carbon (EBC) by using a standard mass absorption cross-section at a given wavelength. However, there is currently a lack of SI traceability for such absorption measurements. In addition, the most common field instruments measure EBC after depositing aerosol particles onto a filter, which introduces complex uncertainties and a need for standardized calibration methods.
The EMPIR Black Carbon project, Metrology for light absorption by atmospheric aerosols (2017 – 2020), aims to establish SI traceability for atmospheric aerosol light absorption measurements, based on filter-free methods such as extinction-minus-scattering, photoacoustic spectroscopy, or photothermal interferometry, as well as standardised calibration routines for filter-based instruments. To this end, its specific objectives are to (1) develop a traceable and primary method for measuring aerosol absorption at specific wavelengths, with defined uncertainties and (2) recommend well-characterized reference aerosols suitable for challenging filter-based instruments. Further co-benefits of this work are (3) the establishment of a set of well-defined physical parameters for the traceable quantification of EBC concentrations and (4) the development of a validated method for the in-situ calibration of filter-based field instruments.
This presentation aims to motivate and summarize the goals of the EMPIR project, which is currently in its early stages, in order to encourage and invite contributions from the community.