ACPD Atmospheric Chemistry and Physics Discussions ACPD 1680-7375 Copernicus GmbH Göttingen, Germany 10.5194/acpd-11-19213-2011 Technical Note: Simple analytical relationships between Ångström coefficients of aerosol extinction, scattering, absorption, and single scattering albedo Moosmüller H. 1 Chakrabarty R. K. 1 Laboratory for Aerosol Science, Spectroscopy, and Optics, Division of Atmospheric Sciences, Desert Research Institute, Nevada System of Higher Education, Reno, NV 89512, USA 05 07 2011 11 7 19213 19222 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys-discuss.net/11/19213/2011/acpd-11-19213-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/11/19213/2011/acpd-11-19213-2011.pdf

Ångström coefficients are commonly used to parameterize the slow wavelength dependence of aerosol scattering, absorption, and extinction coefficients and single scattering albedo. Here we introduce simple analytical relationships between these coefficients that establish a framework for intercomparison between theory and experimental results from different instruments and platforms and allow for closure studies and improved physical understanding.

 References Ångström, A.: On the Atmospheric Transmission of Sun Radiation and on Dust in the Air, Geogr. Ann., 11, 156–166, 1929. Dubovik, O., Holben, B. N., Kaufman, Y. J., Yamasoe, M., Smirnov, A., Tanré, D., and Slutsker, I.: Single-Scattering Albedo of Smoke Retrieved from the Sky Radiance and Solar Transmittance Measured from Ground, J. Geophys. Res., 103, 31903–31923, 1998. Dubovik, O. and King, M. D.: A Flexible Inversion Algorithm for Retrieval of Aerosol Optical Properties from Sun and Sky Radiance Measurements, J. Geophys. Res., 105, 20673–20696, 2000. Eversole, J. D., Lin, H.-B., Huston, A. L., Campillo, A. J., Leung, P. T., Liu, S. Y., and Young, K.: High-Precision Identification of Morphology-Dependent Resonances in Optical Processes in Microdroplets, J. Opt. Soc. Am. B, 10, 1955–1968, 1993. Fischer, E. V., Jaffe, D. A., Marley, N. A., Gaffney, J. S., and Marchany-Rivera, A.: Optical Properties of Aged Asian Aerosols Observed over the US Pacific Northwest, J. Geophys. Res., 115, D20209, http://dx.doi.org/10.1029/2010JD013943doi:10.1029/2010JD013943, 2010. Flowers, B. A., Dubey, M. K., Mazzoleni, C., Stone, E. A., Schauer, J. J., Kim, S.-W., and Yoon, S. C.: Optical-chemical-microphysical relationships and closure studies for mixed carbonaceous aerosols observed at Jeju Island; 3-laser photoacoustic spectrometer, particle sizing, and filter analysis, Atmos. Chem. Phys., 10, 10387–10398, http://dx.doi.org/10.5194/acp-10-10387-2010doi:10.5194/acp-10-10387-2010, 2010. Lewis, K., Arnott, W. P., Moosmüller, H., and Wold, C. E.: Strong Spectral Variation of Biomass Smoke Light Absorption and Single Scattering Albedo Observed with a Novel Dual-Wavelength Photoacoustic Instrument, J. Geophys. Res., 113, D16203, http://dx.doi.org/10.1029/2007JD009699doi:10.1029/2007JD009699, 2008. Mishchenko, M. I., Cairns, B., Kopp, G., Schueler, C. F., Fafaul, B. A., Hansen, J. E., Hooker, R. J., Itchkawich, T., Maring, H. B., and Travis, L. D.: Accurate Monitoring of Terrestrial Aerosols and Total Solar Irradiance – Introducing the Glory Mission, Bull. Amer. Meteor. Soc., 88, 677–691, 2007. Moosmüller, H., Chakrabarty, R. K., and Arnott, W. P.: Aerosol Light Absorption and its Measurement: A Review, J. Quant. Spectrosc. Radiat. Transfer, 110, 844–878, 2009. Moosmüller, H., Chakrabarty, R. K., Ehlers, K. M., and Arnott, W. P.: Absorption Ångström coefficient, brown carbon, and aerosols: basic concepts, bulk matter, and spherical particles, Atmos. Chem. Phys., 11, 1217–1225, http://dx.doi.org/10.5194/acp-11-1217-2011doi:10.5194/acp-11-1217-2011, 2011. Russell, P. B., Bergstrom, R. W., Shinozuka, Y., Clarke, A. D., DeCarlo, P. F., Jimenez, J. L., Livingston, J. M., Redemann, J., Dubovik, O., and Strawa, A.: Absorption Ångström Exponent in AERONET and related data as an indicator of aerosol composition, Atmos. Chem. Phys., 10, 1155–1169, http://dx.doi.org/10.5194/acp-10-1155-2010doi:10.5194/acp-10-1155-2010, 2010. Virkkula, A., Ahlquist, N. C., Covert, D. S., Arnott, W. P., Sheridan, P. J., Quinn, P. K., and Coffman, D. J.: Modification, Calibration and a Field Test of an Instrument for Measuring Light Absorption by Particles, Aerosol Sci. Tech., 39, 68–83, 2005. Zhu, L., Martins, J. V., and Remer, L. A.: Biomass Burning Aerosol Absorption Measurements with MODIS Using the Critical Reflectance Method, J. Geophys. Res., 116, D07202, http://dx.doi.org/10.1029/2010JD015187doi:10.1029/2010JD015187, 2011.