Review of Chang et al.

Abstract

This study utilizes the isotopic composition of nitrate and ammonium captured in cloudwater during a major biomass burning event to delineate the sources and chemistry that contribute to the inorganic N concentrations. Overall, the methods are sound and the study yields interesting results. The interpretation is well constructed, but there are a number of aspects that need to be better justified and better referenced to make the study's findings stronger. Please see below.As motivation for the work, the authors invoke the difficulty of addressing tropospheric cloud formation and its importance for radiative forcing of climate. Further, they state C1