Wintertime Aerosol Measurements during the Chilean Coastal Orographic Precipitation Experiment

Abstract. The Chilean Coastal Orographic Precipitation Experiment (CCOPE) was a three-month field campaign (June, July and August 2015) that investigated wintertime coastal rain events. Reported here are analyses of aerosol measurements made at a coastal site during CCOPE. The aerosol monitoring site was located near Arauco, Chile. Aerosol number concentrations and aerosol size distributions were acquired with a Condensation Particle Counter (CPC) and an Ultra High Sensitivity Aerosol Spectrometer (UHSAS). Arauco CPC concentrations were compared to those measured at the NOAA observatory Trinidad Head (THD) on the North Pacific Coast of California. The winter averaged CPC concentration at Arauco is 2971 cm −3  ± 1802 cm −3 ; at THD the average is 1059 cm −3  ± 855 cm −3 . Despite the typically more pristine Southern Pacific region, the Arauco average is larger than at THD ( p