Abstract
Tropospheric photodissociation rate coefficients (J values) were calculated for NO2, O3, HNO2, CH2O, and CH3CHO using high spectral resolution (0.1 mm wavelength increments), and compared to the J values obtained with numerically degraded resolution (Δλ=1, 2, 4, 6, 8, and 10 nm, and several commonly used nonuniform grids). Depending on the molecule, substantial errors can be introduced by the larger increments. Thus for Δλ=10 nm, errors are less than 1% for NO2, less than 2% for HNO2, +6.5% to -16% for CH2O, -6.9% to +24% for CH3CHO, and -24% to +110% for O3. The errors for CH2O arise from the fine structure of its absorption spectrum, and are prevalently negative (underestimate of J). The errors for O3, and to a lesser extent for CH3CHO, arise mainly from under-resolving the overlap of the molecular action spectrum and the tropospheric actinic flux in the wavelength region of stratospheric ozone attenuation. The sign of those errors depends on whether the actinic flux is averaged onto the grid before or after the radiative transfer calculation. In all cases studied, grids with Δλ≤2 nm produced errors no larger than 5%.
Similar content being viewed by others
References
Bass, A. M., Glasgow, L. C. Miller, C., Jesson, J. P., and Filkin, D. L., 1980, Temperature dependent absorption cross sections for formaldehyde (CH2O): the effect of formaldehyde on stratospheric chlorine chemistry, Planet. Space Sci., 28, 675–679.
Bass, A. M., Ledford, A. E. Jr., and Laufer, A. H., 1976, Extinction coefficients of NO2 and N2O4. J. Res. Nat. Bureau of Standards, 80A, 143–166.
Calvert, J. G. and Pitts, J. N. Jr., 1966, Photochemistry, John Wiley, New York.
Davenport, J. E., 1978, Determination of NO2 photolysis parameters for stratospheric modeling, Final Report, FAA-EQ-78–14, High Altitude Program, Federal Aviation Administration, Office of Environmental Quality, Washington D.C.
Demerjian, K. L., Schere, K. L., and Peterson, J. T., 1980, Theoretical estimates of actinic (spherically integrated) flux and photolytic rate constants of atmospheric species in the lower troposphere, Adv. Envir. Sci. Tech., 10, 369–459.
DeMore, W. B., Margitan, J. J., Molina, M. J., Watson, R. T., Golden, D. M., Hampson, R. F., Kurylo, M. J., Howard, C. J. and Ravishankara, A. R., 1985, Chemical kinetics and photochemical data for use in stratospheric modeling. Evaluation No. 7, JPL Publ. 85–62, National Aeronautics and Space Administration, Jet Propulsion Laboratory, Pasadena.
Elterman, L., 1968, UV, visible, and IR attenuation for altitudes to 50 km, AFCRL-68–0153, No. 285, Air Force Cambridge Research Laboratories, Bedford, MA.
Gardner, E. P., Sperry, P. D., and Calvert, J. G., 1987, Primary quantum yields of NO2 photodissociation, J. Geophys. Res. 92, 6642–6652.
Logan, J. A., Prather, M. J., Wofsy, S. C., and McElroy, M. B., 1981, Tropospheric chemistry: a global perspective, J. Geophys. Res., 86, 7210–7254.
Joseph, J. H., Wiscombe, W. J., and Weinman, J. A., 1976, The delta-Eddington approximation for radiative flux transfer, J. Atmos. Sci., 33, 2452–2459.
Madronich, S., 1987, Photodissociation in the atmosphere I. Actinic flux and the effects of ground reflections and clouds, J. Geophys. Res., 92, 9740–9752.
Mentall, J. E., Frederick, J. E., and Herman, J. R., 1981, The solar irradiance from 200 to 330 nm, J. Geophys. Res. 86, 9881–9884.
Meyrahn H., 1984, Bildungswege und analytik des peroxy acetyl nitrate (PAN) in der atmosphäre, Ph.D. thesis, Fachbereich Chemie der Johannes Gutenberg-Universität, Mainz Germany.
Meyrahn, H., Moortgat, G. K., and Warneck, P., 1981, The photolysis of acetaldehyde under atmospheric conditions, Fifth Two-Annual Colloquium of the Sonderforschungsbereich 73 of the Universities Frankfurt and Mainz and the Max-Plank-Institut Mainz, Mainz Germany, 1 July.
Moortgat, G. K., Klippel, W., Mobus, K. H., Seiler, W., and Warneck, P., 1980, Laboratory measurement of photolytic parameters for formaldehyde, Final Report, FAA-EE-80–47, Federal Aviation Administration, Office of Environment and Energy, Washington, D.C.
Neckel, H. and Labs, D., 1984, The solar radiation between 3300 and 12500 A, Solar Physics 90, 205–258.
Nicolet, M., Meier, R. R., and Anderson, D. E. Jr., 1982, Radiation field in the troposphere and stratosphere-II, numerical analysis, Planet. Space Sci. 30, 935–983.
WMO, 1986, Atmospheric ozone 1985. Assessment of our understanding of the processes controlling its present distribution and change, Report No. 16, World Meteorological Organization, Global Ozone Research and Monitoring Project, Geneva.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Madronich, S., Weller, G. Numerical integration errors in calculated tropospheric photodissociation rate coefficients. J Atmos Chem 10, 289–300 (1990). https://doi.org/10.1007/BF00053864
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00053864