Deutsches Zentrum für Luft- und Raumfahrt e.V. German Aerospace Center Institut für Physik der Atmosphäre Atmosphärische Aerosole The Multi-Angle Absorption Photometer for the Determination of Black Carbon in Ambient Aerosol CARUSSO A. Petzold 1, M. Schönlinner 2, H.Kramer 2 and H. Schloesser 2 1 Institut für Physik der Atmosphäre, Deutsches Zentrum für Luft- und Raumfahrt Oberpfaffenhofen, Wessling, Germany 2 ESM Andersen Instruments, Frauenauracher Str. 96, Erlangen, Germany

Deutsches Zentrum für Luft- und Raumfahrt e.V. German Aerospace Center Institut für Physik der Atmosphäre Atmosphärische Aerosole Determination of the black carbon (BC) content in ambient aerosol by means of an extinction measurement on filter- deposited aerosol samples. Measurement of transmitted and reflected radiation in angular-resolved mode. Reduction of measurement uncertainties, which are related to multiple scattering of radiation by aerosol particles and between the aerosol layer and the filter substrate, by applying a radiative transfer scheme to the data analysis. The Multi-Angle Absorption Photometer for the Determination of Black Carbon in Ambient Aerosol Optical sensor head

Deutsches Zentrum für Luft- und Raumfahrt e.V. German Aerospace Center Institut für Physik der Atmosphäre Atmosphärische Aerosole The aerosol is deposited in the top layer of a fiber filter matrix, which is termed as aerosol-filter layer. A two-stream approximation is applied to calculate the radiative properties of the aerosol-filter layer from the radiative transfer equation. Required input values are the measured filter transmittance trans and reflectance ref. The algorithm determines optical thickness of the aerosol-filter layer L single-scattering albedo of the aerosol-filter layer 0 Derived properties are aerosol-filter layer absorbance ABS = 100 L ( ) BC mass loading of the filter ABS = ABS S BC Data Analysis Algorithm

Deutsches Zentrum für Luft- und Raumfahrt e.V. German Aerospace Center Institut für Physik der Atmosphäre Atmosphärische Aerosole The instrument is set up as a filter tape device. time resolution 2 min sampling volume m 3 h -1 detection limit (1 m 3 h -1, 2 min)10 -6 m ng m -3 Instrument Capabilities

Deutsches Zentrum für Luft- und Raumfahrt e.V. German Aerospace Center Institut für Physik der Atmosphäre Atmosphärische Aerosole Design of the Multi Angle Absorption Photometer - CARUSSO