ACAPEXICENUCLEI

ARM Cloud Aerosol Precipitation Experiment (ACAPEX): Ship-Based Ice Nuclei Collections

14 January 2015 - 12 February 2015

Lead Scientist: Paul DeMott

Observatory: AMF (ARM Mobile Facility 2) - ACX

Measurements are sought to evaluate a hypotheses that sea spray-sourced ice nucleating particles (INP) are of biological origin and represent a distinctly different INP population in comparison to long range transported desert or urban and regional land-sourced INP, and that the layering of marine within other aerosol layers feeding orographic storms over the mountains of California and the Western U.S. thereby leads to common and quantifiable scenarios that influence precipitation over the region. Aerosol collections on the NOAA Ron Brown for subsequent processing of INP activation temperature spectra and composition analyses, add a valuable measurement to the ACAPEX and related CalWater2 (NOAA) studies for use in parameterizing and modeling the impacts of marine boundary layer and other aerosols on climate and radiation via aerosol-indirect effects on mixed phase clouds. These INP measurements supplemented multiple airborne INP measurements on the AAF, and others on the ground during ACAPEX to provide extensive spatial and temporal analyses of INP immersion freezing spectra during winter storm periods.