“…Particle scattering is a third, and largely independent, source of bias. The integrating plate's design minimizes its response to nonabsorbing particles, but collected particles unavoidably cause some increase in the fraction of incident illumination that is lost to backscattering and thereby miscounted as absorption (Clarke 1982: Hanel et al 1982. This scattering interference is commonly treated as an additive bias that scales with the scattering coefficient of the sampled aerosol (Reid et al 1998;Bond et al 1999;Weingartner et al 2003), as discussed in the following paragraph.…”