Air Pollution, Aerosols and Clouds in the Climate System

Source identification for atmospheric aerosol is important for developing effective strategy to reduce their emissions. One of the methods for source identification is principal components analysis (PCA). My attention was drawn to this method recently first through a review article about methods and results for aerosol source apportionment over European region and then through the article “ Identification of PM sources by principal component analysis (PCA) coupled with wind direction ”. Dr. Viana Rodríguez, Mª del Mar is the lead author on both the articles . She is a researcher at the Institute of Earth Sciences Jaume Almera , Spain. Application of the principal components analysis method for aerosol is based on the foundation that each source has unique blending of various aerosol components. Variability of the components is strongly correlated among themselves when they are coming from same source when compared to a case where they are coming from heterogeneous sources. Mathemat...

In recent years, the role of atmospheric aerosols is being increasingly recognized both in climate system of Earth and in global biogeochemical cycle. Aerosols affect the radiative balance of the Earth directly by scattering or absorbing incoming shortwave radiation and indirectly by acting as cloud condensation nuclei, altering a temperature effect at the surface because of changes in cloud cover. In addition, aerosol particles are closely coupled to atmospheric chemistry as chemical reactions in the atmosphere are often accelerated on aerosol surfaces. Also, the chemistry of aerosols may alter their physical and optical properties such as size distribution (fine to coarse) due to interaction between acidic (sulpahte, nitrate) and alkaline (mineral dust) aerosols; single scattering albedo (because of coating of one type of aerosols over other); and surface properties (hydrophilic/hydrophobic), and thus, their direct and indirect effects on climate change. Long range transport and depo...