Strong Aerosol Effects on Cloud Amount Based on Long?Term Satellite Observations Over the East Coast of the United States

Here, we use 16-year satellite and reanalysis data in combination with a multivariate regression model to investigate how aerosols affect cloud fraction (CF) over the East Coast of United States. Cloud droplet number concentrations (Nd), geometrical thickness, lower tropospheric stability, relative humidity at 950 hPa (RH950) are identified as major controlling parameters that explain 97% variability CF. Nd is shown play an important role regulating dependence CF on RH950. The observed annual-mean shows no significant trend due cancellation from opposite trends revealed decline alone would lead about 20% Our results indicate aerosol effects suggest need account for pollution-induced changes quantifying feedback based long-term observations.