Journal ArticleDOI
Chemical mechanisms of acid generation in the troposphere
Jack G. Calvert,Allan L. Lazrus,Gregory L. Kok,Brian G. Heikes,James Walega,John A. Lind,Christopher A. Cantrell +6 more
TLDR
In this article, it was shown that gaseous hydrogen peroxide is a major oxidant leading to sulphuric acid generation in cloud water, and computer simulations can now rationalize the observed seasonal trends.Abstract:
Diverse chemical pathways in the troposphere convert sulphur and nitrogen oxides and organic compounds into acids, involving the gas phase, the liquid phase (cloud, fog and rain water) and, possibly, certain suspended aerosols. The rates of acid generation are critically affected by the extent of generation of the oxidizing species and the kinetics of the reactions. Precipitation in the eastern United States shows a strong seasonal variation in deposition of sulphates in contrast to nitrates. Computer simulations can now rationalize the observed seasonal trends. Recent tropospheric measurements of gaseous hydrogen peroxide show that this gas is a major oxidant leading to sulphuric acid generation in cloud water.read more
Citations
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Parameterization of surface resistances to gaseous dry deposition in regional-scale numerical models
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The second generation regional acid deposition model chemical mechanism for regional air quality modeling
TL;DR: The Regional Acid Deposition Model (RADM2) as discussed by the authors is a state-of-the-art gas phase chemical mechanism for modeling atmospheric chemistry on a regional scale.
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Nucleation and Growth of Nanoparticles in the Atmosphere
TL;DR: Nucleation and Growth of Nanoparticles in the Atmosphere Renyi Zhang,* Alexei Khalizov, Lin Wang, Min Hu, and Wen Xu.
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Isotopic studies of nitrogen pollution in the hydrosphere and atmosphere: A review
TL;DR: A review of the use of 15N/14N ratios in investigating sources and mechanisms of pollution in the hydrosphere is given in this paper, where it is shown that these differences are largely the result of kinetic isotope fractionation associated with bacterially-mediated reactions.
References
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Journal ArticleDOI
Factors controlling the acidity of natural rainwater
TL;DR: In this article, the authors suggest that there are integral constraints imposed by (1) the requirement for mass continuity in each elemental cycle and (2) the relative concentrations of soluble species and liquid water in cloudy air; these factors must be mutually consistent.
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The free radical chemistry of cloud droplets and its impact upon the composition of rain
TL;DR: In this article, the authors simulate the free radical chemistries of the gas phase and aqueous phase within a warm cloud during midday solar fluxes and demonstrate that the scavenging of OH and HO2 from cloud droplets can represent a major source of free radicals to cloud water provided the accommodation or sticking coefficient for these species impinging upon water droplets is not less than 0.0001.
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The mechanism of the HO-SO2 reaction
TL;DR: In this paper, the authors used long-path Fourier transform infrared spectroscopy to follow the chemical changes in irradiated HONO, CO, SO2, NOx, O2N2 gaseous mixtures.
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The importance of atmospheric ozone and hydrogen peroxide in oxidising sulphur dioxide in cloud and rainwater
TL;DR: In this paper, the authors used the experimental data to calculate the rate of sulphate formation in water droplets under atmospheric conditions for each of the three oxidants, i.e., ozone, ozone and hydrogen peroxide.
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Acid deposition and forest decline.
TL;DR: The authors find several possible pathways for acid deposition to contribute to spruce mortality, but none are supported by convincing evidence and there is evidence for the triggering effect of drought in a situation of multiple stresses.