The effect of atmospheric nitric acid vapor on cloud condensation nucleus activation

Abstract

Activation and growth of cloud condensation nuclei are investigated. A one‐dimensional cloud model including detailed microphysics is developed. The system studied consists of NaNO3 particles and condensing water and HNO3 vapors. According to numerical simulations, enhanced concentrations of atmospheric nitric acid vapor affect cloud formation by increasing the number of cloud droplets and decreasing their mean size compared to circumstances where no condensable vapors other than water are present. It is argued that the cloud albedo increases because of these effects.

The Environmental Control of Individual Aqueous Particles in a Cubic Electrodynamic Levitation System

“…Such nitric acid saturation ratios are just barely attained in moderately polluted urban environments (Spicer, 1982), but at lower temperatures, such as those found in the Arctic troposphere or in the stratosphere, the ambient values of S, are likely to increase by one to two orders of magnitude. The implications of such behavior on cloud formation have been explored theoretically (Lamb, 1992;Kulmala et al, 1993;Carslaw et al, 1994), but to our knowledge the direct measurement of the enhanced mass growth of aqueous particles due to the presence of nitric acid vapor has not been made before. In general, we expect that haze and cloud formation is stimulated in the atmosphere whenever suitably large saturation ratios of a soluble trace gas are present.…”

Impact of gas‐phase HNO3 and NH3 on microphysical processes in atmospheric clouds

“…Nevertheless, it has only been relatively recently that the impact of a trace gas on aerosol modulation of cloud microphysics has been assessed, specifically, the impact of HNO 3 vapor on the activation of cloud condensation nuclei (CCN) and thus the cloud drop number concentration (CDNC). Kulmala et al [1993] first suggested that atmospheric HNO 3 could alter the activation and growth of CCN significantly, offering a theoretical analysis utilizing a relatively simple system consisting of NaNO 3 particles and HNO 3 vapor. A more complete evaluation of this issue was subsequently carried out by Laaksonen et al [1998], using an aerosol consisting of slightly soluble CaSO 4 cores coated with (NH4)2SO 4, and gas phase HNO 3.…”

Preliminary Study on the Visualization and Quantification of Elemental Compositions in Individual Microdroplets using Solidification and Synchrotron Radiation Techniques

“…Sulfates, sodium chloride, other water-soluble salts, and inorganic acids are common components of atmospheric aerosol and often act as CCN (Hudson and Da, 1996). Although the CCN activities of inorganic aerosol substances are well known, highly soluble gases, such as HNO 3 and HCl, can also be dissolved into growing solution droplets prior to activation (Laaksonen et al, 1998;Kulmula et al, 1993).…”