Review of Evaluation of equivalent black carbon (EBC) source appointment using observations from Switzerland between 2008 and 2018 by S. Grange et al.

Abstract

Grange et al. present an evaluation of source apportionment via the aethalometer model from six Swiss sites. They compare their obtained fossil and wood burning fractions from the model to expected diurnal patterns and ambient temperature. They also compare the aerosol Ångstroem exponents (AAE) they use in the model to the binned AAEs of the full (non-apportioned) time series. Finally, they also show and discuss the trends in fossil/ wood burning fractions. This article is informative the figures are well designed and illustrative. However, there are some important issues regarding the data processing, at least as it is outlined in the text. I also note that the technical aspects of the paper are not as in depth as work by e.g. (Fuller et al., 2014) or (Zotter et al., 2017) who compare their data to external tracers, such that an experienced user