“…The CCN activity of aerosols, namely the fraction of particles activated into cloud droplets, can be directly measured by the continuous‐flow streamwise thermal‐gradient CCN counter (CCNC). The most commonly used CCNC was developed and commercialized by Droplet Measurement Technologies (DMT) (Lance et al., 2006; Roberts & Nenes, 2005), which has been widely applied in both field observation and laboratory experiment of aerosol CCN activity (Gohil & Asa‐Awuku, 2022; Kerminen et al., 2012; Kuang, Xu, et al., 2020; Paramonov et al., 2015; Tomi Raatikainen et al., 2013). This instrument consists of a continuous flow tube in which the walls are kept saturated with water and a positive wall temperature gradient is maintained.…”