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Description of aethalometer

The aethalometer is a filter-based method for evaluating light absorbing aerosol.

General Information

The aethalometer is used to measure light absorbing aerosol in near real time. The instrument reports equivalent black carbon concentration as a function of wavelength, but also reports changes in optical transmission caused by particle deposition on the filter. The change in transmission is related to the light absorption coefficient via Beers law (see discussion here). Older aethalometers used white light or operated at 1 wavelength (nominally 880 nm) while newer models (e.g., AE31, AE33) measure at 7 wavelengths (370, 470, 520, 590, 660, 880 and 950 nm).

More details about aethalometer operations are provided in the selecton of references below.

  • AE33 - Drinovec et al., "The “dual-spot” Aethalometer: an improved measurement of aerosol black carbon with real-time loading compensation," Atmos. Meas. Tech., 8, 1965–1979, 2015.
  • AE31 corrections - Collaud Coen et al., "Minimizing light absorption measurement artifacts of the Aethalometer: evaluation of five correction algorithms," Atmos. Meas. Tech., 3, 457–474, https://doi.org/10.5194/amt-3-457-2010, 2010.
  • Intercomparisons - Muller et al. "Characterization and intercomparison of aerosol absorption photometers: result of two intercomparison workshops," Atmos. Meas. Tech., 4, 245–268, https://doi.org/10.5194/amt-4-245-2011, 2011.
  • Original - Hansen et al., "The aethalometer — An instrument for the real-time measurement of optical absorption by aerosol particles," Sci. Tot. Environ., 1984.