An Observed Signature of Aerosol Effect on Cloud Droplet Radii from a Decade of Observations at a Mid-Continental Site
| Min, Qilong | State University of New York at Albany |
| Duan, Minzheng | State University of New York at Albany |
| Harrison, Lee | State University of New York |
| Joseph, Everette | Howard University |
Category: Aerosols
Continuing observations of aerosol and cloud optical property have been made using MFRSR and MWR at the ARM SGP site since 1993. Diurnal, monthly, seasonal and interannual variability of aerosol (optical depth and Angstrom coefficient) and cloud (optical depth and effective radius) have been analyzed. We have correlated an “aerosol index” computed from clear-sky observations of MFRSR with cloud droplet mean effective radius to study the “Twomey effect”. In these data we see a robust signature for indirect aerosol modulation of cloud droplet radii during summer seasons; no correlation is evident for winter and fall seasons. This correlation is significant for seasonal averages classified by liquid water path and also for the population of same-day observations. The indirect effect decreases with liquid water path at both seasonal scale and daily-pair.
This poster will be displayed at the ARM Science Team Meeting.
