The SOLEDAD campaign consisted of ground-based measurements located near the peak of Mt. Soledad, 251 m above sea level at 1 km from the Pacific coast. Measurements collected for 49 days (1 May to 18 June, 2012) include: particle-cloud partitioning of elemental carbon [Schroder et al., 2014], and salt particle contributions to cloud droplets [Modini et al., 2015]. Measurements on 1 June and 13 June, 2012, of two cloud events contained sufficient observations for characterizing droplet size and composition of the stratocumulus clouds. Chemical composition and aerosol size distribution used to initialize the models were collected inside the instrument container; instruments for cloud measurements were mounted on top. We assumed particle composition was internally mixed and independent of size because size-dependent AMS measurements were below detection limit for the relevant sampling periods and no measurements of bulk mixing state were carried out. Two inlets were used to sample ambient aerosols: the high-flow rate isokinetic inlet continuously collected air containing both interstitial aerosols and cloud droplets and a counterflow virtual impactor (CVI) was used to sample only cloud droplet residuals [Noone et al., 1988; Schroder et al., 2014]. The CVI inlet for droplet residuals was mounted atop the container and was only used during cloud events. During periods with no clouds, all instruments sampled through the isokinetic inlet. Two single-particle soot photometers (SP2, DMT, Boulder, CO) were used to measure refractory elemental carbon: one continuously measured from the isokinetic inlet and the other measured from the residual inlet during cloud events.
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