Atmospheric Radiation Measurement Climate Research Facility US Department of Energy



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

14 January 2015 - 12 February 2015

Lead Scientist: Paul DeMott

Observatory: AMF, 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.


Sonia Kreidenweis
L. Ruby Leung

Related Publications


DeMott PJ and TC Hill. 2016. ACAPEX – Ship-Based Ice Nuclei Collections Field Campaign Report. Ed. by Robert Stafford, DOE ARM Climate Research Facility. DOE/SC-ARM-16-029.

View All Related Publications

Campaign Data Sets

IOP Participant Data Source Name Final Data
Paul DeMott Ice Nucleation Spectrometer - Ronald H. Brown Order Data

ACX Data Sources

Name Full Name Browse Data
AERI Atmospheric Emitted Radiance Interferometer Browse Data
AOS Aerosol Observing System Browse Data
AOSMET Meteorological Measurements associated with the Aerosol Observing System Browse Data
CCN Cloud Condensation Nuclei Particle Counter Browse Data
CEIL Ceilometer Browse Data
CPC Condensation Particle Counter Browse Data
CSPHOT Cimel Sunphotometer Browse Data
HSRL High Spectral Resolution Lidar Browse Data
HTDMA Humidified Tandem Differential Mobility Analyzer Browse Data
IRT Infrared Thermometer Browse Data
KAZR Ka ARM Zenith Radar Browse Data
LDIS Laser Disdrometer Browse Data
LSSONDE Microwave Radiometer-Scaled Sonde Profiles Browse Data
MPL Micropulse Lidar Browse Data
MPLCMASK Cloud mask from Micropulse Lidar Browse Data
MWACR Marine W-Band (95 GHz) ARM Cloud Radar Browse Data
MWR Microwave Radiometer Browse Data
MWR3C Microwave Radiometer, 3 Channel Browse Data
NAV Navigational Location and Attitude Browse Data
NEPHELOMETER Nephelometer Browse Data
OZONE Ozone Monitor Browse Data
PBLHT Planetary Boundary Layer Height Browse Data
PRP Portable Radiation Package Browse Data
PSAP Particle Soot Absorption Photometer Browse Data
RWP Radar Wind Profiler Browse Data
SONDE Balloon-Borne Sounding System Browse Data
S-TABLE Stabilized Platform Browse Data
TSI Total Sky Imager Browse Data