Radioactive aerosols differ physically from non-radioactive aerosols by the appreciable charge that they may carry. This arises from a competition between the charge generated by the radioactive decays occurring within each aerosol and the subsequent diffusion of the ions formed back onto the particle. At high levels of activity, the particles may self-discharge, at low and intermediate activit...

The role of convection in introducing aerosols and promoting the formation of new particles to the upper troposphere has been examined using a cloud-resolving model coupled with an interactive explicit aerosol module. A baseline simulation suggests good agreement in the upper troposphere between modeled and observed results including concentrations of aerosols in different size ranges, mole fra...

[1] Using a CIMEL Sun photometer, we conducted continuous observations over the urban area of Shanghai (31 14′N, 121 32′E) from 18 April 2007 to 31 January 2009. The aerosol optical depth (AOD), Angstrom wavelength exponent, single scattering albedo (w0), and aerosol particle size distribution were derived from the observational data. The monthly mean AOD reached a maximum value of 1.20 in June...

The fate of aerosols in open flows is relevant in a variety of physical contexts. Previous results are consistent with the assumption that such finite-size particles always escape in open chaotic advection. Here we show that a different behavior is possible. We analyze the dynamics of aerosols both in the absence and presence of gravitational effects, and both when the dynamics of the fluid par...

Tiny airborn particles including those released by human activities and the secondary organic aerosols have potential impacts on the hydrologic cycle. This review briefly introduces the aerosols formation, potential feedback between the aerosols and hydrologic cycle. Recent progress in aerosols, cloud and precipitation is described. The current status using model tools to investigate the intera...

Mechanisms for the formation of Type I (nitric acid-based) polar stratospheric louds (PSCs) are discussed. If the pre-existing sulfate aerosols are liquid prior to PSC formation, then nitric acid particles (Type Ib) form by HNO 3 dissolution in aqueous H2SO,• solution droplets. This process does not require a nucleation step for the formation of HNO3 aerosols, so most pre-existing aerosols grow...

The cycling of atmospheric aerosols through clouds can change their chemical and physical properties and thus modify how aerosols affect cloud microphysics and, subsequently, precipitation and climate. Current knowledge about aerosol processing by clouds is rather limited to chemical reactions within water droplets in warm low-altitude clouds. However, in cold high-altitude cirrus clouds and an...

Previous laboratory studies and in situ measurements have shown that dust particles possess the ability to nucleate ice crystals, and smoke particles to some extent as well. Even with coatings of pollutants such as sulphate and nitrate on the surface of dust particles, it has been shown that polluted dust particles are still able to nucleate ice in the immersion, deposition, condensation, and c...

A total of 834 individual aerosol particles were collected during October and November 2010 in urban Shanghai, China. Particles were sampled under different weather and air quality conditions. Morphologies, compositions and mixing states of carbonaceous aerosols were investigated by transmission electron microscopy (TEM) coupled with energy-dispersive X-ray (EDX). Structures of some particles w...