Experimental studies investigating the properties and processes occurring in aerosol may be broadly split into two categories — ensemble measurements and single particle measurements. Ensemble measurements are made on the whole aerosol dispersion and measure the averaged properties of the system. Single particle measurements reduce the complexity of an ensemble aerosol and measure the properties of individual droplets. Experimental studies of atmospheric aerosol may be further categorized into field measurements and laboratory studies. Field measurements observe aerosol in the natural environment and are typically focused on providing estimates of droplet number concentrations and chemical compositions. Laboratory measurements generally probe more idealized systems in order to elucidate the influence of specific factors on the response of aerosol. Atmospheric aerosol are also the subject of modelling studies which aim to quantify their influence in the atmosphere and predict both the local and global effects of aerosol.
Laboratory measurements allow the mechanisms included in atmospheric models to be refined and provide an essential link between field measurements and model predictions. This approach bridging model simulations, laboratory measurements, and observation is a highly effective strategy for understanding complex systems where numerous coupled processes are at work.