




                                                         Roy Barnes
                                                         Barbara Emery
                                                         Art Richmond
                                                         June 1989


  Section M

  UPPER ATMOSPHERE (mostly 80    1000 km)


  A detailed catalogue of these upper atmosphere data is available, which
  provides greater detail than this summary.

   A.  Ionospheric Incoherent-Scatter Radar Data

       The radars can measure electron and ion densities, tem-
       peratures, and velocities between about 90 km and 1000
       km altitude.  From these measurements, neutral atmos-
       pheric temperatures and winds can be deduced. The
       datasets do not always include all altitudes or all
       parameters. Data are typically available for a one- to
       three-day period each month.

       Current holdings:

       Jicamarca, Peru                (12    S, 76    W) 1966 - 1969, 1971 - 72, 1984 - 1988
       Arecibo, Puerto Rico           (18    N, 67    W) 1974 - 1977, 1981 - 1988
       Millstone Hill, MA             (43    N, 71    W) 1978 - 1979, 1983 - 1987
       Chatanika, Alaska              (65    N, 147    W) 1977 - 1982*
       Sondre Stromfjord, Greenland   (67    N, 51    W) 1983 - 1988
       St. Santin, France             (45    N, 2    E) 1966 - 1982, 1984 - 1987**
       EISCAT (Tromso, Norway)        (70    N, 19    E) 1984 - 1988

       *During 1982 the Chatanika radar was moved to establish Sondre Stromfjord.
       **After 1987 St. Santin terminated incoherent scatter measurements.

   B.  Fabry-Perot Interferometer

       Measures neutral gas temperature and velocity.  The altitude of measurement
       may not be known precisely (but can be inferred with additional data), and
       can range from 90 to 500 km.
       Current holding:
       Sondre Stromfjord (67    N, 51    W) 1988 nominally 250 km.

   C.  MST Radar

       Mesosphere - Stratosphere Doppler radars measure neutral wind velocity
       (and turbulence) over altitudes from 0 to 100 km.
       Current holding:
       Poker Flat, Alaska (65    N, 147    W) hourly averages, more or less
       continuous from 1979 - 1985.











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   D.  Empirical Descriptions of Standard Conditions, 60 km      1000 km

        1.  The Chiu Model will produce height profiles of
            electron density for specified location, time and
            sunspot number.

        2.  The International Reference Ionosphere, IRI, model
            produces electron density, neutral temperature,
            electron temperature, ion temperature and ion con-
            centrations for five species (O+, H+, He+, O2
                                                         +,
            NO+) given location, time and sunspot number.

        3.  The Mass Spectrometer Incoherent Scatter, MSIS,
            model produces neutral atmosphere parameters (tem-
            perature, exopheric temperature and Ar, O2, N2, O,
            N, He, H concentrations) given a number of geophy-
            sical indices.  The 1983 and 1986 versions are
            available.

   E.  Model Data Assimilation Analyses of the Ionosphere

       Assimilative mapping of ionospheric electrodynamics:
       Provides electric potential patterns, electric fields,
       and height-integrated conductivities over the northern
       hemisphere above 50    magnetic latitude.  Patterns are
       derived from a variety of data sources (magnetometers,
       IS radars, coherent radars, satellite measurements of
       electron precipitation) starting with statistical pat-
       terns applicable to the geophysical conditions.

   F.  General Circulation Model Results

        1.  The Thermosphere (/Ionosphere) General Circulation
            Model

            Provides global coverage on a 5x5    grid between
            97 km and 500-700 km of neutral and ionized ther-
            mospheric parameters, including neutral winds,
            neutral temperatures, neutral compositions (N2,
            O2, O), electron density, electron temperature,
            ion temperature and ion composition (O+, O2
                                                       +).
            Model inputs of ion velocity and auroral deposi-
            tion parameters are also provided.

        2.  Semi-diurnal tidal model:  Provides amplitudes and
            phases of the semi-diurnal tide in the horizontal
            neutral wind, neutral temperature and geopotential
            between 0 and 100 km as a function of latitude and
            season.












