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Module astronomy_mod

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OVERVIEW

astronomy_mod provides astronomical variables for use by other modules within fms. the only currently used interface is for determination of astronomical values needed by the shortwave radiation packages.


OTHER MODULES USED

         fms_mod
time_manager_mod
   constants_mod

PUBLIC INTERFACE

astronomy_init:
astronomy_init is the constructor for astronomy_mod.
get_period_integer:
get_period_integer returns the length of the year as an integer number of seconds.
get_period_time_type:
get_period_time_type returns the length of the year as a time_type variable.
set_period_integer:
set_period_integer saves as the input length of the year (an integer) in a time_type module variable.
set_orbital_parameters:
set_orbital_parameters saves the input values of eccentricity, obliquity and perihelion time as module variables for use by astronomy_mod.
get_orbital_parameters:
get_orbital_parameters retrieves the orbital parameters for use by another module.
set_ref_date_of_ae:
set_ref_date_of_ae provides a means of specifying the reference date of the NH autumnal equinox for a particular year.
get_ref_date_of_ae:
get_ref_date_of_ae retrieves the reference date of the autumnal equinox as integer variables.
diurnal_solar_2d:
diurnal_solar_2d returns 2d fields of cosine of zenith angle, daylight fraction and earth-sun distance at the specified lati- tudes, longitudes and time. these values may be instantaneous or averaged over a specified time interval.
diurnal_solar_1d:
diurnal_solar_1d takes 1-d input fields, adds a second dimension and calls diurnal_solar_2d. on return, the 2d fields are returned to the original 1d fields.
diurnal_solar_0d:
diurnal_solar_0d takes scalar input fields, makes them into 2d arrays dimensioned (1,1), and calls diurnal_solar_2d. on return, the 2d fields are converted back to the desired scalar output.
diurnal_solar_cal_2d:
diurnal_solar_cal_2d receives time_type inputs, converts them to real variables and then calls diurnal_solar_2d to compute desired astronomical variables.
diurnal_solar_cal_1d:
diurnal_solar_cal_1d receives time_type inputs, converts them to real variables and then calls diurnal_solar_2d to compute desired astronomical variables.
diurnal_solar_cal_0d:
diurnal_solar_cal_0d receives time_type inputs, converts them to real variables and then calls diurnal_solar_2d to compute desired astronomical variables.
daily_mean_solar_2d:
daily_mean_solar_2d computes the daily mean astronomical parameters for the input points at latitude lat and time of year time_since_ae.
daily_mean_solar_1d:
daily_mean_solar_1d takes 1-d input fields, adds a second dimension and calls daily_mean_solar_2d. on return, the 2d fields are returned to the original 1d fields.
daily_mean_solar_2level:
daily_mean_solar_2level takes 1-d input fields, adds a second dimension and calls daily_mean_solar_2d. on return, the 2d fields are returned to the original 1d fields.
daily_mean_solar_0d:
daily_mean_solar_1d takes 1-d input fields, adds a second dimension and calls daily_mean_solar_2d. on return, the 2d fields are returned to the original 1d fields.
daily_mean_solar_cal_2d:
daily_mean_solar_cal_2d receives time_type inputs, converts them to real variables and then calls daily_mean_solar_2d to compute desired astronomical variables.
daily_mean_solar_cal_1d:
daily_mean_solar_cal_1d receives time_type inputs, converts them to real, 2d variables and then calls daily_mean_solar_2d to compute desired astronomical variables.
daily_mean_solar_cal_2level:
daily_mean_solar_cal_2level receives 1d arrays and time_type input, converts them to real, 2d variables and then calls daily_mean_solar_2d to compute desired astronomical variables.
daily_mean_solar_cal_0d:
daily_mean_solar_cal_0d converts scalar input fields to real, 2d variables and then calls daily_mean_solar_2d to compute desired astronomical variables.
annual_mean_solar_2d:
annual_mean_solar_2d returns 2d fields of annual mean values of the cosine of zenith angle, daylight fraction and earth-sun distance at the specified latitude.
annual_mean_solar_1d:
annual_mean_solar_1d creates 2-d input fields from 1-d input fields and then calls annual_mean_solar_2d to obtain 2-d output fields which are then stored into 1-d fields for return to the calling subroutine.
annual_mean_solar_2level:
annual_mean_solar_2level creates 2-d input fields from 1-d input fields and then calls annual_mean_solar_2d to obtain 2-d output fields which are then stored into 1-d fields for return to the calling subroutine. this subroutine will be called during model initialization.
astronomy_end:
astronomy_init is the destructor for astronomy_mod.
orbit:
orbit computes and stores a table of value of orbital angles as a function of orbital time (both the angle and time are zero at autumnal equinox in the NH, and range from 0 to 2*pi).
r_inv_squared:
r_inv_squared returns the inverse of the square of the earth-sun distance relative to the mean distance at angle ang in the earth's orbit.
angle:
angle determines the position within the earth's orbit at time t in the year ( t = 0 at NH autumnal equinox.) by interpolating into the orbital position table.
declination:
declination returns the solar declination angle at orbital position ang in earth's orbit.
half_day_2d:
half_day_2d returns a 2-d array of half-day lengths at the latitudes and declination provided.
half_day_0d:
half_day_0d takes scalar input fields, makes them into 2-d fields dimensioned (1,1), and calls half_day_2d. on return, the 2-d fields are converted to the desired scalar output.
orbital_time:
orbital time returns the time (1 year = 2*pi) since autumnal equinox
universal_time:
universal_time returns the time of day at longitude = 0.0 (1 day = 2*pi)

PUBLIC DATA

None.

PUBLIC ROUTINES

  1. astronomy_init

    call astronomy_init (latb, lonb)
    DESCRIPTION
    astronomy_init is the constructor for astronomy_mod.


    INPUT
    latb    array of model latitudes at cell boundaries [radians]
       [real]
    lonb    array of model longitudes at cell boundaries [radians]
       [real]

  2. get_period_integer

    call get_period_integer (period_out)
    DESCRIPTION
    get_period_integer returns the length of the year as an integer number of seconds.


    OUTPUT
    period_out    number of seconds as the length of the year
       [integer]

  3. get_period_time_type

    call get_period_time_type (period_out)
    DESCRIPTION
    get_period_time_type returns the length of the year as a time_type variable.


    OUTPUT
    period_out    the length of the year as a time_type
       [time_type]

  4. set_period_integer

    call set_period_integer (period_in)
    DESCRIPTION
    set_period_integer saves as the input length of the year (an integer) in a time_type module variable.


    INPUT
    period_in    the length of the year as a time_type
       [time_type]

  5. set_orbital_parameters

    call set_orbital_parameters (ecc_in, obliq_in, per_in)
    DESCRIPTION
    set_orbital_parameters saves the input values of eccentricity, obliquity and perihelion time as module variables for use by astronomy_mod.


    INPUT
    ecc_in    eccentricity of orbital ellipse
       [real]
    obliq_in    obliquity fof orbital ellipse
       [real]
    per_in    longitude of perihelion with respect to autumnal equinox in northern hemisphere
       [real]

  6. get_orbital_parameters

    call get_orbital_parameters (ecc_out, obliq_out, per_out)
    DESCRIPTION
    get_orbital_parameters retrieves the orbital parameters for use by another module.


    OUTPUT
    ecc_out    eccentricity of orbital ellipse
       [real]
    obliq_out    obliquity fof orbital ellipse
       [real]
    per_out    longitude of perihelion with respect to autumnal equinox in northern hemisphere
       [real]

  7. set_ref_date_of_ae

    call set_ref_date_of_ae (day_in,month_in,year_in, & second_in,minute_in,hour_in)
    DESCRIPTION
    set_ref_date_of_ae provides a means of specifying the reference date of the NH autumnal equinox for a particular year. it is only used if calls are made to the calandar versions of the routines diurnal_solar and daily_mean_solar. if the NOLEAP calendar is used, then the date of autumnal equinox will be the same every year. if JULIAN is used, then the date of autumnal equinox will return to the same value every 4th year.


    INPUT
    day_in    day of reference autumnal equinox
       [integer]
    month_in    month of reference autumnal equinox
       [integer]
    year_in    year of reference autumnal equinox
       [integer]
    second_in    OPTIONAL: second of reference autumnal equinox
       [real]
    minute_in    OPTIONAL: minute of reference autumnal equinox
       [real]
    hour_in    OPTIONAL: hour of reference autumnal equinox
       [real]

  8. get_ref_date_of_ae

    call get_ref_date_of_ae (day_out,month_out,year_out, & second_out, minute_out,hour_out)
    DESCRIPTION
    get_ref_date_of_ae retrieves the reference date of the autumnal equinox as integer variables.


    OUTPUT
    day_out    day of reference autumnal equinox
       [integer]
    month_out    month of reference autumnal equinox
       [integer]
    year_out    year of reference autumnal equinox
       [integer]
    second_out    second of reference autumnal equinox
       [real]
    minute_out    minute of reference autumnal equinox
       [real]
    hour_out    hour of reference autumnal equinox
       [real]

  9. diurnal_solar_2d

    call diurnal_solar_2d (lat, lon, gmt, time_since_ae, cosz, & fracday, rrsun, dt_time)
    DESCRIPTION
    diurnal_solar_2d returns 2d fields of cosine of zenith angle, daylight fraction and earth-sun distance at the specified lati- tudes, longitudes and time. these values may be instantaneous or averaged over a specified time interval.


    INPUT
    lat    latitudes of model grid points
       [real]
    lon    longitude of model grid points
       [real]
    gmt    time of day at longitude 0.0; midnight = 0.0, one day = 2 * pi
       [real]
    time_since_ae    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [real]
    dt    OPTIONAL: time interval after gmt over which the astronomical variables are to be averaged. this produces averaged output rather than instantaneous.
       [real]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  10. diurnal_solar_1d

    call diurnal_solar_1d (lat, lon, gmt, time_since_ae, cosz, & fracday, rrsun, dt)
    DESCRIPTION
    diurnal_solar_1d takes 1-d input fields, adds a second dimension and calls diurnal_solar_2d. on return, the 2d fields are returned to the original 1d fields.


    INPUT
    lat    latitudes of model grid points
       [real]
    lon    longitude of model grid points
       [real]
    gmt    time of day at longitude 0.0; midnight = 0.0, one day = 2 * pi
       [real]
    time_since_ae    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [real]
    dt    OPTIONAL: time interval after gmt over which the astronomical variables are to be averaged. this produces averaged output rather than instantaneous.
       [real]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  11. diurnal_solar_0d

    call diurnal_solar_0d (lat, lon, gmt, time_since_ae, cosz, & fracday, rrsun, dt)
    DESCRIPTION
    diurnal_solar_0d takes scalar input fields, makes them into 2d arrays dimensioned (1,1), and calls diurnal_solar_2d. on return, the 2d fields are converted back to the desired scalar output.


    INPUT
    lat    latitudes of model grid points
       [real]
    lon    longitude of model grid points
       [real]
    gmt    time of day at longitude 0.0; midnight = 0.0, one day = 2 * pi
       [real]
    time_since_ae    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [real]
    dt    OPTIONAL: time interval after gmt over which the astronomical variables are to be averaged. this produces averaged output rather than instantaneous.
       [real]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  12. diurnal_solar_cal_2d

    call diurnal_solar_cal_2d (lat, lon, gmt, time_since_ae, cosz, & fracday, rrsun, dt)
    DESCRIPTION
    diurnal_solar_cal_2d receives time_type inputs, converts them to real variables and then calls diurnal_solar_2d to compute desired astronomical variables.


    INPUT
    lat    latitudes of model grid points
       [real]
    lon    longitude of model grid points
       [real]
    gmt    time of day at longitude 0.0; midnight = 0.0, one day = 2 * pi
       [real]
    time_since_ae    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [real]
    dt_time    OPTIONAL: time interval after gmt over which the astronomical variables are to be averaged. this produces averaged output rather than instantaneous.
       [time_type]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  13. diurnal_solar_cal_1d

    call diurnal_solar_cal_1d (lat, lon, gmt, time_since_ae, cosz, & fracday, rrsun, dt)
    DESCRIPTION
    diurnal_solar_cal_1d receives time_type inputs, converts them to real variables and then calls diurnal_solar_2d to compute desired astronomical variables.


    INPUT
    lat    latitudes of model grid points
       [real]
    lon    longitude of model grid points
       [real]
    gmt    time of day at longitude 0.0; midnight = 0.0, one day = 2 * pi
       [real]
    time_since_ae    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [real]
    dt_time    OPTIONAL: time interval after gmt over which the astronomical variables are to be averaged. this produces averaged output rather than instantaneous.
       [time_type]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  14. diurnal_solar_cal_0d

    call diurnal_solar_cal_0d (lat, lon, gmt, time_since_ae, cosz, & fracday, rrsun, dt_time)
    DESCRIPTION
    diurnal_solar_cal_0d receives time_type inputs, converts them to real variables and then calls diurnal_solar_2d to compute desired astronomical variables.


    INPUT
    lat    latitudes of model grid points
       [real]
    lon    longitude of model grid points
       [real]
    gmt    time of day at longitude 0.0; midnight = 0.0, one day = 2 * pi
       [real]
    time_since_ae    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [real]
    dt_time    OPTIONAL: time interval after gmt over which the astronomical variables are to be averaged. this produces averaged output rather than instantaneous.
       [time_type]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  15. daily_mean_solar_2d

    call daily_mean_solar_2d (lat, time_since_ae, cosz, h_out, rr_out)
    DESCRIPTION
    daily_mean_solar_2d computes the daily mean astronomical parameters for the input points at latitude lat and time of year time_since_ae.


    INPUT
    lat    latitudes of model grid points
       [real]
    time_since_ae    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [real]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    h_out    2-d array of half-day lengths at the latitudes
       [real]
    rr_out    the inverse of the square of the earth-sun distance relative to the mean distance at angle ang in the earth's orbit.
       [real]

  16. daily_mean_solar_1d

    call daily_mean_solar_1d (lat, time_since_ae, cosz, h_out, rr_out)
    DESCRIPTION
    daily_mean_solar_1d takes 1-d input fields, adds a second dimension and calls daily_mean_solar_2d. on return, the 2d fields are returned to the original 1d fields.


    INPUT
    lat    latitudes of model grid points
       [real]
    time_since_ae    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [real]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    h_out    2-d array of half-day lengths at the latitudes
       [real]
    rr_out    the inverse of the square of the earth-sun distance relative to the mean distance at angle ang in the earth's orbit.
       [real]

  17. daily_mean_solar_2level

    call daily_mean_solar_2level (lat, time_since_ae, cosz, solar)
    DESCRIPTION
    daily_mean_solar_2level takes 1-d input fields, adds a second dimension and calls daily_mean_solar_2d. on return, the 2d fields are returned to the original 1d fields.


    INPUT
    lat    latitudes of model grid points
       [real]
    time_since_ae    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [real]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    solar    shortwave flux factor: cosine of zenith angle * daylight fraction / (earth-sun distance squared)
       [real]

  18. daily_mean_solar_0d

    call daily_mean_solar_0d (lat, time_since_ae, cosz, h_out, rr_out)
    DESCRIPTION
    daily_mean_solar_1d takes 1-d input fields, adds a second dimension and calls daily_mean_solar_2d. on return, the 2d fields are returned to the original 1d fields.


    INPUT
    lat    latitudes of model grid points
       [real]
    time_since_ae    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [real]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    h_out    2-d array of half-day lengths at the latitudes
       [real]
    rr_out    the inverse of the square of the earth-sun distance relative to the mean distance at angle ang in the earth's orbit.
       [real]

  19. daily_mean_solar_cal_2d

    call daily_mean_solar_cal_2d (lat, time, cosz, fracday, rrsun)
    DESCRIPTION
    daily_mean_solar_cal_2d receives time_type inputs, converts them to real variables and then calls daily_mean_solar_2d to compute desired astronomical variables.


    INPUT
    lat    latitudes of model grid points
       [real]
    time    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [time_type]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  20. daily_mean_solar_cal_1d

    call daily_mean_solar_cal_1d (lat, time, cosz, fracday, rrsun)
    DESCRIPTION
    daily_mean_solar_cal_1d receives time_type inputs, converts them to real, 2d variables and then calls daily_mean_solar_2d to compute desired astronomical variables.


    INPUT
    lat    latitudes of model grid points
       [real]
    time    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [time_type]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  21. daily_mean_solar_cal_2level

    call daily_mean_solar_cal_2level (lat, time, cosz, solar)
    DESCRIPTION
    daily_mean_solar_cal_2level receives 1d arrays and time_type input, converts them to real, 2d variables and then calls daily_mean_solar_2d to compute desired astronomical variables.


    INPUT
    lat    latitudes of model grid points
       [real]
    time    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [time_type]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    solar    shortwave flux factor: cosine of zenith angle * daylight fraction / (earth-sun distance squared)
       [real]

  22. daily_mean_solar_cal_0d

    call daily_mean_solar_cal_0d (lat, time, cosz, fracday, rrsun)
    DESCRIPTION
    daily_mean_solar_cal_0d converts scalar input fields to real, 2d variables and then calls daily_mean_solar_2d to compute desired astronomical variables.


    INPUT
    lat    latitudes of model grid points
       [real]
    time    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [time_type]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  23. annual_mean_solar_2d

    call annual_mean_solar_2d (js, je, lat, cosz, solar, fracday, & rrsun)
    DESCRIPTION
    annual_mean_solar_2d returns 2d fields of annual mean values of the cosine of zenith angle, daylight fraction and earth-sun distance at the specified latitude.


    INPUT
    js, je    Starting/ending index of latitude window
       [real]
    lat    latitudes of model grid points
       [real]
    time    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [time_type]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    solar    shortwave flux factor: cosine of zenith angle * daylight fraction / (earth-sun distance squared)
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  24. annual_mean_solar_1d

    call annual_mean_solar_1d (jst, jnd, lat, cosz, solar, & fracday, rrsun_out)
    DESCRIPTION
    annual_mean_solar_1d creates 2-d input fields from 1-d input fields and then calls annual_mean_solar_2d to obtain 2-d output fields which are then stored into 1-d fields for return to the calling subroutine.


    INPUT
    jst, jnd    Starting/ending index of latitude window
       [real]
    lat    latitudes of model grid points
       [real]
    time    time of year; autumnal equinox = 0.0, one year = 2 * pi
       [time_type]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    solar    shortwave flux factor: cosine of zenith angle * daylight fraction / (earth-sun distance squared)
       [real]
    fracday    daylight fraction of time interval
       [real]
    rrsun_out    earth-sun distance (r) relative to semi-major axis of orbital ellipse (a) : (a/r)**2
       [real]

  25. annual_mean_solar_2level

    call annual_mean_solar_2level (lat, cosz, solar)
    DESCRIPTION
    annual_mean_solar_2level creates 2-d input fields from 1-d input fields and then calls annual_mean_solar_2d to obtain 2-d output fields which are then stored into 1-d fields for return to the calling subroutine. this subroutine will be called during model initialization.


    INPUT
    lat    latitudes of model grid points
       [real]

    OUTPUT
    cosz    cosine of solar zenith angle
       [real]
    solar    shortwave flux factor: cosine of zenith angle * daylight fraction / (earth-sun distance squared)
       [real]

  26. astronomy_end

    call astronomy_end
    DESCRIPTION
    astronomy_init is the destructor for astronomy_mod.


  27. orbit

    call orbit
    DESCRIPTION
    orbit computes and stores a table of value of orbital angles as a function of orbital time (both the angle and time are zero at autumnal equinox in the NH, and range from 0 to 2*pi).


  28. r_inv_squared

    r = r_inv_squared (ang)
    DESCRIPTION
    r_inv_squared returns the inverse of the square of the earth-sun distance relative to the mean distance at angle ang in the earth's orbit.


    INPUT
    ang    angular position of earth in its orbit, relative to a value of 0.0 at the NH autumnal equinox, value between 0.0 and 2 * pi
       [real]

  29. angle

    r = angle (t)
    DESCRIPTION
    angle determines the position within the earth's orbit at time t in the year ( t = 0 at NH autumnal equinox.) by interpolating into the orbital position table.


    INPUT
    t    time of year (between 0 and 2*pi; t=0 at NH autumnal equinox
       [real]

  30. declination

    r = declination (ang)
    DESCRIPTION
    declination returns the solar declination angle at orbital position ang in earth's orbit.


    INPUT
    ang    solar orbital position ang in earth's orbit
       [real]

  31. half_day_2d

    h = half_day_2d (latitude, dec)
    DESCRIPTION
    half_day_2d returns a 2-d array of half-day lengths at the latitudes and declination provided.


    INPUT
    latitude    latitutde of view point
       [real]
    dec    solar declination angle at view point
       [real]

  32. half_day_0d

     
half_day_0d
    DESCRIPTION
    half_day_0d takes scalar input fields, makes them into 2-d fields dimensioned (1,1), and calls half_day_2d. on return, the 2-d fields are converted to the desired scalar output.


    INPUT
    latitude    latitutde of view point
       [real]
    dec    solar declination angle at view point
       [real]

  33. orbital_time

    t = orbital_time (time)
    DESCRIPTION
    orbital time returns the time (1 year = 2*pi) since autumnal equinox; autumnal_eq_ref is a module variable of time_type and will have been defined by default or by a call to set_ref_date_of_ae; length_of_year is available through the time manager and is set at the value approriate for the calandar being used


    INPUT
    time    time (1 year = 2*pi) since autumnal equinox
       [time_type]

  34. universal_time

    t = universal_time (time)
    DESCRIPTION
    universal_time returns the time of day at longitude = 0.0 (1 day = 2*pi)


    INPUT
    time    time (1 year = 2*pi) since autumnal equinox
       [time_type]

DATA SETS

None.

ERROR MESSAGES

None.

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