Stratosphere hydrogen

Jaramillo, M, DeZafra RL, Barrett J, et al. 1989. Measurements of stratospheric hydrogen cyanide and McMurdo Station, Antarctica Further evidence of winter stratospheric subsidence J Geophys Res 94 16,773-16,777. 

Wallace, L W. Livingston, and D. N. B. Hall, A Twenty-Five Year Record of Stratospheric Hydrogen Chloride, Geophys. Res. Lett., 24, 2363-2366 (1997). 

Chance K.V. and Traub W.A., An upper limit for stratospheric hydrogen peroxide. Starnberger See, West Germany, 11-16 January 1984. 

Chance, K.V., D.G. Johnson, W.A. Traub, and K.W. Jucks, Measurement of the stratospheric hydrogen peroxide concentration profile using far infrared thermal emission spectroscopy. Geophys Res Lett 18, 1003, 1991. 

Coffey, M.T., W.G. Mankin, and R.J. Cicerone, Spectrascopic detection of stratospheric hydrogen cyanide. Science 214, 333, 1981a. 

Some hydrogen cyanide is formed whenever hydrocarbons (qv) are burned in an environment that is deficient in air. Small concentrations are also found in the stratosphere and atmosphere. It is not clear whether most of this hydrogen cyanide comes from biological sources or from high temperature, low oxygen processes such as coke production, but no accumulation has been shown (3). 

Recently, there have also been some concerns over possible problems related to hydrogen gas leakage as the molecular hydrogen leaks from most containment vessels. It has been hypothesized that if significant amounts of H2 escape to stratosphere, FT free radicals can be formed due to ultraviolet radiation, which in turn can enhance the ozone depletion. However, the effect of these leakage problems may not be significant as the amount of hydrogen that leaks presently is much lower (by a factor of 10-100) than the hypothesized 10-20%. 

Thiemens MH, Heidenreich JE (1983) The mass independent fractionation of oxygen a novel isotope effect and its possible cosmochemical implications. Science 219 1073-1075 Thiemens MH, Jackson TL, Brenninkmeijer CAM (1995) Observation of a mass-independent oxygen isotopic composition in terrestrial stratospheric COj, the link to ozone chemisdy, and the possible occurrence in the Martian atmosphere. Geophys Res Lett 22 255-257 Timmes FX, Woosley SE, Weaver TA(1995) Galactic chemical evolution hydrogen through zinc. Astrophys J Suppl 98 617-658... 

Tromp TK, Sbia RL, Allen M, Filer JM, Yung YL (2003) Potential environmental impact of a hydrogen economy on the stratosphere. Science 300 1740-1742... 

Abstract Heterogeneous chemical reactions at the surface of ice and other stratospheric aerosols are now appreciated to play a critical role in atmospheric ozone depletion. A brief summary of our theoretical work on the reaction of chlorine nitrate and hydrogen chloride on ice is given to highlight the characteristics of such heterogeneous mechanisms and to emphasize the special challenges involved in the realistic theoretical treatment of such reactions. 

During the dark, polar winter the temperature drops to extremely low values, on the order of-80°C. At these temperatures, water and nitric acid form polar stratospheric clouds. Polar stratospheric clouds are important because chemical reactions in the stratosphere are catalyzed on the surface of the crystals forming these clouds. The chemical primarily responsible for ozone depletion is chlorine. Most of the chlorine in the stratosphere is contained in the compounds hydrogen chloride, HCl, or chlorine nitrate, CIONO. Hydrogen chloride and chlorine nitrate undergo a number of reactions on the surface of the crystals of polar stratospheric clouds. Two important reactions are ... 

Figure 4.33 shows the absorption cross sections of HC1 and HBr at room temperature (DeMore et al., 1997 Huebert and Martin, 1968). Neither absorb above 290 nm, so their major tropospheric fates are deposition or reaction with OH. Even in the stratosphere, photolysis is sufficiently slow that these hydrogen halides act as temporary halogen reservoirs (see Chapter 12). 

Schneider, J., V. Burger, and F. Arnold, Methyl Cyanide and Hydrogen Cyanide Measurements in the Lower Stratosphere Implications for Methyl Cyanide Sources and Sinks, . /. Geophys. Res., 102, 25501-25506 (1997). 

Zander, R., C. P. Rinsland, C. B. Farmer, J. Namkung, R. H. Norton, and J. M. Russell III, Concentrations of Carbonyl Sulfide and Hydrogen Cyanide in the Free Upper Troposphere and Lower Stratosphere Deduced from ATMOS/Spacelab 3 Infrared Solar Occultation Spectra, . /. Geophys. Res., 93, 1669-1678(1988). 

While there are a variety of other chlorinated organics such as methylchloroform (CH3CC13) that are emitted, these have relatively short tropospheric lifetimes because they have an abstractable hydrogen atom (e.g., see WMO, 1995). For example, while the stratospheric lifetime of methylchloroform is estimated to be 34 7 years (Volk et al., 1997), its overall atmospheric lifetime is only 5-6 years, primarily due to the removal by OH in the troposphere (toii 6.6 years), with a much smaller contribution from uptake by the ocean (roi i an 85 years) (WMO, 1995). 

Tolbert, M. A., M. J. Rossi, R. Malhotra, and D. M. Golden, Reaction of Chlorine Nitrate with Hydrogen Chloride and Water at Antarctic Stratospheric Temperatures, Science, 238, 1258-1260 (1987). 

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