Fluorescence characteristics of water-soluble organic carbon in atmospheric aerosol

Fluorescence spectroscopy is a commonly used technique to analyze dissolved organic matter in aquatic environments. Given the high sensitivity and non-destructive analysis, fluorescence has recently been used to study water-soluble organic carbon (WSOC) in atmospheric aerosols, which have substantial abundance, various sources and play an important role in climate change. Yet, current research on WSOC characterization is rather sparse and limited to a few isolated sites, making it challenging to draw fundamental and mechanistic conclusions. Here we presented a review of the fluorescence properties of atmospheric WSOC reported in various field and laboratory studies, to discuss the current advances and limitations of fluorescence applications. We highlighted that photochemical reactions and relevant aging processes have profound impacts on fluorescence properties of atmospheric WSOC, which were previously unnoticed for organic matter in aquatic environments. Furthermore, we discussed the differences in sources and chemical compositions of fluorescent components between the atmosphere and hydrosphere. We concluded that the commonly used fluorescence characteristics derived from aquatic environments may not be applicable as references for atmospheric WSOC. We emphasized that there is a need for more systematic studies on the fluorescence properties of atmospheric WSOC and to establish a more robust reference and dataset for fluorescence studies in atmosphere based on extensive source specific experiments. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

Fluorescence spectroscopy is commonly used to analyze dissolved organic matter in aquatic environments, and its application in atmospheric aerosols has been increasing. However, current research on WSOC characterization in the atmosphere is still limited and presents challenges. Studies focus on the impact of photochemical reactions and aging processes on fluorescence properties of atmospheric WSOC, as well as the differences in fluorescent components between the atmosphere and hydrosphere.