Barbara Bertozzi

1. Introduction Click to copy section linkSection link copied! Black carbon (BC) is a side product of incomplete combustion. Here we use the simplified term BC for referring to soot BC, as defined in Corbin et al. (2019), that consists primarily of graphitic sp2-bonded carbon with soot BC particles being aggregates of primary spherules. (1) BC is the primary contributor to light absorption by aerosols in the visible spectrum, (2) and it is associated with adverse health effects.

Abstract New particle formation in the upper free troposphere is a major global source of cloud condensation nuclei (CCN)1,2,3,4. However, the precursor vapours that drive the process are not well understood. With experiments performed under upper tropospheric conditions in the CERN CLOUD chamber, we show that nitric acid, sulfuric acid and ammonia form particles synergistically, at rates that are orders of magnitude faster than those from any two of the three components.