In the framework of the ChArMEx (the Chemistry-Aerosol Mediterranean Experiment; http://charmex.lsce.ipsl.fr/) program, the seasonal variability of the aerosol optical, microphysical and radiative properties derived from AERONET (Aerosol Robotic Network; http://aeronet.gsfc.nasa.gov/) is examined in two regional background insular sites in the western Mediterranean Basin: Ersa (Corsica Island, ...

Organic chemistry in aerosol water has recently been recognized as a potentially important source of secondary organic aerosol (SOA) material. This SOA material may be surface-active, therefore potentially affecting aerosol heterogeneous activity, ice nucleation, and CCN activity. Aqueous aerosol chemistry has also been shown to be a potential source of light-absorbing products ("brown carbon")...

Our long-term goal is to establish an improved understanding of the factors that control the marine aerosol properties and concentrations as they relate to generation processes, mixing processes, their dependence on oceanic and environmental conditions and physicochemical evolution in the marine boundary layer. We expect these efforts to lead to improved modeling and predictability of marine ae...

Various types of aerosols affect cloud microphysical properties and cloud lifetime through the so-called “indirect effect”. The decrease of particles size when the cloud is polluted by small aerosol particles serving as additional cloud condensation nuclei and the reduction of the efficiency of the precipitation forming processes are phenomena described in numerous recent studies (Bréon et al. ...

Central China is important for aerosols and climate because it is among the worst regions for air pollution in China. However, it is understudied due to a lag in establishing an atmospheric monitoring network. So we did a comprehensive analysis using multiple techniques to improve the understanding of aerosol optical properties and their radiative effect in this region. The results showed that ...

Using the GlobAEROSOL-AATSR dataset, estimates of the instantaneous, clear-sky, direct aerosol radiative effect and radiative forcing have been produced for the year 2006. Aerosol Robotic Network sun-photometer measurements have been used to characterise the random and systematic error in the GlobAEROSOL product for 22 regions covering the globe. Representative aerosol properties for each regio...

Accurate visibility forecasts, being necessary for military operations and field applications of opticallysensitive equipment such as advanced electro-optical (EO) systems, remain as a challenging scientific problem. One reason is because large spatial and temporal variations exist, not only with aerosol physical and optical properties, but with emission sources. Clearly, to further advance aer...

[1] A cloud masking algorithm based on the spatial variability of reflectances at the top of the atmosphere in visible wavelengths was developed for the retrieval of aerosol properties by MODIS. It is shown that the spatial pattern of cloud reflectance as observed from space, is very different from that of aerosols. Clouds show a very high spatial variability in the scale of hundred meters to f...

Over the past decade, the number of studies that investigate aerosol–cloud interactions has increased considerably. Although tremendous progress has been made to improve the understanding of basic physical mechanisms of aerosol–cloud interactions and reduce their uncertainties in climate forcing, there is still poor understanding of 1) some of the mechanisms that interact with each other over m...

[1] We present direct radiometric observations of aerosol radiative forcing during the ACE-Asia experiment (March and April of 2001). The observational analysis is based on radiometer data obtained from the NOAA ship Ronald H. Brown, and shipboard measurements of the aerosol chemical and scattering properties are used to construct a model of the aerosol optical properties for use in radiative t...