Cloud Aerosol Research in the Marine Atmosphere (CARMA)

• A multi-year project to look primarily at the interaction of aerosols and clouds in the marine atmosphere.

• A concurrent, ancillary task has been to characterize, both chemically and physically, the aerosols in the MBL

Proposed CARMA-IV Goals

• Hygroscopicity climatology for litoral region

• Assess the relative importance of super-inversion mixing and below cloud aerosol on cloud optical depth

• Assess the impact of precipitation scavenging on MBL aerosol concentration

Potential New Goals

• Assess the importance of EC particles as CCN

• Evaluate the impact of chemistry on aerosol hygroscopicity during vertical transport in the MBL

• Explore relationship between individual particle hygroscopicity and bulk scattering hygroscopicity

Instruments for Proposed Goals

Instruments for Potential Goals

Hygroscopicity Parameters

• For light scattering dependence:

• For particle size dependence:

DHGF’s (wet to dry diameter ratio)

Hygroscopicity data for Climatology