ISDACHTDMA

ISDAC / RISCAM - Humidified Tandem Differential Mobility Analyzer (HTDMA)

1 April 2008 - 30 June 2008

Lead Scientist: Don Collins

Observatory: NSA

In conjunction with the ISDAC project, a Humidified Tandem Differential Mobility Analyzer (HDTMA) was used to characterize the size-resolved hygroscopicity of an aerosol. When coupled with a concurrently measured aerosol size distribution, these data can be employed: i) to predict the humidity dependent optical properties and CCN spectra of the aerosol population; ii) to constrain the atmospheric processes responsible for changes in particle size and properties; and iii) to isolate the properties and impact of a single particle type that is present in an external mixture. These measurements were particularly valuable for quantifying the contribution of specific classes of particles to the total CCN concentration.