In the middle and high latitude atmosphere below 100 km altitude the principal sources of ionization are l) solar radiation in the x–ray and extreme ultraviolet wavelengths, 2) galactic cosmic rays and other galactic radiations, and 3) precipitating energetic particles of solar origin and from the earth’s radiation belts. In this paper the relative contribution of each of these source terms to the maintenance of the dynamic ionosphere is reviewed. The significant role of electron precipitation and the associated bremsstrahlung to the ionization and modification of the neutral atmosphere is presented. The important role of solar particle events in both ionizing the atmosphere and in producing and modifying key minor neutral constituents such as ozone, atomic oxygen, and the nitric oxides is illustrated.


Magnetic Storm Stratospheric Ozone Solar Proton Event Electron Precipitation Magnetic Latitude 
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  1. Aiken, A.C., 1971, Review presented at COSPAR Symposium on D and E Region Ion Chemistry, Urbana, Illinois, 6–9 July 1971.Google Scholar
  2. Bailey, D.K., R.R. Brown, M. H. Rees, 1970, J. Geophys. Res, 75, 7l6l.CrossRefGoogle Scholar
  3. Banks, P.M., G. Kockarts, 1973, Aeronomy, Academic Press, New York.Google Scholar
  4. Bauer, S.J., 1973, Physics of Planetary Ionospheres, Springer-Verlag Publ. Co., New York.Google Scholar
  5. Belrose, J.S., L. Thomas, 1968, J. Atmos. Terr. Phys, 30, 1397.CrossRefGoogle Scholar
  6. Coffey, H., 1973, Collected Data Reports on August 1972 Solar–Terrestrial Event, Parts I, II, and I II, U.S. Dept. of Commerce, Environmental Data Service, Ashville, N. Car.Google Scholar
  7. Crutzen, P.J., I.S.A. Isaksen, G. C. Reid, 1975, Science, 189, 457.CrossRefGoogle Scholar
  8. Gunton, R.C., R.E. Meyerott, J.B. Reagan, 1977, Lockheed Report D556351, Ion and Neutral Chemistry of the D-Region during the Intense Solar Particle Event of August 1972.Google Scholar
  9. Heath, D. F., A. J. Krueger, P.J. Crutzen, 1976, NASA-GSFC Report X-912-76-172, Influence of a Solar Proton Event on Stratospheric Ozone.Google Scholar
  10. Heaps, M.G., 1976, USA Ballistic Research Laboratories Report 2641, The Ion Pair Production Rate Due to Cosmic Rays.Google Scholar
  11. Imhof, W.L., G. H. Nakano, E. E. Gaines, J. B. Reagan, 1975, J. Geophys. Res, 80, 3622.CrossRefGoogle Scholar
  12. Imhof, W.L., T. R. Larsen, J. B. Reagan, and E. E. Gaines, 1976, Lockheed Report D502063, Analysis of Satellite Data on Precipitating Particles in Coordination with ELF Propagation Anomalies.Google Scholar
  13. Imhof, W.L., J. B. Reagan, E.E. Gaines, 1977, EOS, 58, 464.Google Scholar
  14. Isaksen, I.S.A., 1974, ELF–VLF Radio Wave Propagation, ed. J. Holtet, D. Reidel Publ. Co., Dordrecht-Holland.Google Scholar
  15. Johnson, R.G., W.L. Imhof, 1973, NASA Report SP-366, Possible Relationship Between Solar Activity and Meteorological Phenomena, 89.Google Scholar
  16. Larsen, T.R., J.B. Reagan, W.L. Imhof, L.E. Montbriand, J. S. Belrose, 1976a, J. Geophys. Res, 81, 2200.CrossRefGoogle Scholar
  17. Larsen, T.R., W.L. Imhof, J.B. Reagan, 1976b, J. Geophys. Res, 81, 3444.CrossRefGoogle Scholar
  18. Lauter, E.A., R. Knuth, 1967, J. Atmos. Terr. Phys, 29, 411.CrossRefGoogle Scholar
  19. Lyons, L.R., D. J. Williams, 1975, J. Geophys. Res, 80, 3985.CrossRefGoogle Scholar
  20. Maehlum, B., 1967, J. Geophys. Res, 72, 2287.CrossRefGoogle Scholar
  21. Manson, A.H., M.J.W. Merry, 1971, J. Atmos. Terr. Phys, 33, 413.CrossRefGoogle Scholar
  22. Manson, A.H., 1972, Radio Science, 7, 57.CrossRefGoogle Scholar
  23. Newkirk, L.L., W.E. Francis, M. Walt, 1974, Lockheed Report D407007, BREMGAT, A Code for the Generation and Transport of Bremsstrahlung through the Atmosphere.Google Scholar
  24. Paulikas, G.A., 1975, Reviews of Geophysics and Space Physics, 13, 709.CrossRefGoogle Scholar
  25. Potemra, T.A., A.J. Zmuda, 1970, J. Geophys. Res, 75, 7161.CrossRefGoogle Scholar
  26. Potemra, T.A., 1973, Physics and Chemistry of the Upper Atmospheres, ed. B. M. McCormac, D. Reidel Publ. Co., Dordrecht-Holland.Google Scholar
  27. Potemra, T.A., T.J. Rosenberg, 1973, J. Geophys. Res, 78, 1572.CrossRefGoogle Scholar
  28. Potemra, T.A., 1974, ELF-VLF Radio Wave Propagation, ed. J. Holtet, D. Reidel Publ. Co., Dordrecht-Holland.Google Scholar
  29. Reagan, J.B., T. M. Watt, 1976, J. Geophys. Res, 81, 4579.CrossRefGoogle Scholar
  30. Reagan, J.B., W.L. Imhof, 1976, EOS, 57, 972.Google Scholar
  31. Rees, M.H., 1969, Space Science Reviews, 10, 413.CrossRefGoogle Scholar
  32. Spjeldvik, W.N., R.M. Thorne, 1975, J. Atmos. Terr. Phys, 37, 777.CrossRefGoogle Scholar
  33. Swider, W., T.J. Keneshea, 1973, Planet. Space Sci, 21, 1969–1973.CrossRefGoogle Scholar
  34. Thomas, L., 1971, J. Atmos. Terr. Phys, 33, 157.CrossRefGoogle Scholar
  35. Thorne, R.M., E.J. Smith, R.K. Burton, R.E. Holzer, 1973, J. Geophys. Res, 78, 1581.CrossRefGoogle Scholar
  36. Thorne, R.M., 1977, Science, 195, 287–289.CrossRefGoogle Scholar
  37. Ulwick, J., 1972, ed., AFCRL Report 72-O474, Proceedings of COSPAR Symposium on Solar Particle Event of November 1969.Google Scholar
  38. Walt, M., W.M. McDonald, W.E. Francis, 1968, Physics of the Magnetosphere, ed. R. Carovillano, J.F. McClay, Reinhold Publ. Co., New York, New York.Google Scholar
  39. Weeks, L.H., R.S. Cuikay, J.R. Corbin, 1972, J. Atmos. Sci, 29, 1138.CrossRefGoogle Scholar
  40. Zmuda, A.J., 1966, J. Geophys. Res, 71, 1911.Google Scholar

Copyright information

© D. Reidel Publishing Company, Dordrecht, Holland 1977

Authors and Affiliations

  • J. B. Reagan
    • 1
  1. 1.Lockheed Palo Alto Research LaboratoryPalo AltoUSA

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