Journal ArticleDOI
The photochemistry of a remote marine stratiform cloud
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TLDR
In this article, coupled gas and aqueous-phase photochemistry of a stratiform cloud in a remote region of the marine atmosphere is investigated with a time-dependent box model.Abstract:
The coupled gas- and aqueous-phase photochemistry of a stratiform cloud in a remote region of the marine atmosphere is investigated with a time-dependent box model. Both scavenging of ambient acidic aerosols and gases as well as aqueous-phase chemical reactions within droplets are found to be important sources of acidity to cloud water and can lead to pH levels in cloud water in the remote marine atmosphere well below 5.6. The major sources of acidity via aqueous-phase chemical reactions are the generation of sulfuric acid from dissolved SO2 and the generation of formic acid from dissolved formaldehyde. In both cases, aqueous-phase free radicals can play a significant role either directly by oxidizing dissolved SO2 and HCHO or indirectly by producing the aqueous-phase oxidant H2O2. The rate of SO2 conversion to sulfuric acid is sensitive to a variety of parameters including the accommodation or sticking coefficient for SO2, H2O2, HO2, and OH, the liquid water content, and the ambient levels of SO2, HNO3, and other acidic or basic gases. Because high levels of SO2 tend to deplete cloud water of H2O3, the possibility exists that the pH of precipitation in polluted regions will respond nonlinearly to reduced SO2 emissions.read more
Citations
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Journal ArticleDOI
Cloud influence on ozone diurnal cycle in the marine boundary layer at Réunion Island
P.J Brémaud,F Taupin +1 more
TL;DR: In this paper, the influence of clouds on the diurnal cycle of ozone concentration in the Reunion Island marine boundary layer is investigated, and it is shown that the relative efficiency of these two ozone sinks depends on the time of day, since the first dominates the second one in early morning and in late afternoon, while the contrary is observed at midday.
Modélisation tri-dimensionnelle globale de la chimie et du transport des gaz en trace dans la troposphère
TL;DR: The IMAGES model as mentioned in this paper, a numerical chemistry/transport model of tropospheric trace gases, is used to study the possible perturbations of the oxidation capacity of the atmosphere, e.g., an increase of trace gas emissions by human activities, a decrease of the stratospheric ozone column, or a climatic perturbation.
Book ChapterDOI
The Role of Water in Organic Aerosol Multiphase Chemistry: Focus on Partitioning and Reactivity
Journal ArticleDOI
Oxidation of cholesterol and O-protected derivatives by the environmental pollutant NO₂.
TL;DR: Exposure of O-protected and free cholesterol to NO2˙ under exclusion of water leads to nitroimine nitrates through a non-radical mechanism, which reveals the high susceptibility of the π system to oxidative damage.
Journal ArticleDOI
An evaluation of the effect of reductions in ambient levels of primary pollutants on sulfate and nitrate wet deposition
TL;DR: In this paper, the effect of reductions in the initial gas phase concentrations of SO 2, NO x and reactive hydrocarbons on sulfate and nitrate production and deposition under precipitating conditions is studied using a one-dimensional time-dependent version of the STEM-II model.
References
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Book
CRC Handbook of Chemistry and Physics
TL;DR: CRC handbook of chemistry and physics, CRC Handbook of Chemistry and Physics, CRC handbook as discussed by the authors, CRC Handbook for Chemistry and Physiology, CRC Handbook for Physics,
Chemical kinetics and photochemical data for use in stratospheric modeling
W. B. Demore,J. J. Margitan,Mario J. Molina,R. T. Watson,D. M. Golden,R. F. Hampson,Michael J. Kurylo,Carleton J. Howard,A. R. Ravishankara +8 more
TL;DR: As part of a series of evaluated sets, rate constants and photochemical cross sections compiled by the NASA Panel for Data Evaluation are provided in this article, with particular emphasis on the ozone layer and its possible perturbation by anthropogenic and natural phenomena.
Journal ArticleDOI
Tropospheric chemistry: A global perspective
TL;DR: A model for the photochemistry of the global troposphere constrained by observed concentrations of H2O, O3, CO, CH4, NO, NO2, and HNO3 is presented in this paper.
Book
Selected values of chemical thermodynamic properties
TL;DR: The Selected Values of Chemical Thermodynamic Properties as mentioned in this paper, published by the National Bureau of Standards (NBS) in 1952, is a seminal work in the field of thermodynamics.