nrlmsise00._nrlmsise00

Interface to the NRLMSISE-00 C library.

gtd7(year, doy, sec, alt, g_lat, g_long, ...)	MSIS Neutral Atmosphere Empircial Model from the surface to lower exosphere.
gtd7d(*args, **kwargs)	MSIS Neutral Atmosphere Empircial Model from the surface to lower exosphere.

NRLMSISE-00 wrapper module

nrlmsise00._nrlmsise00.gtd7(year, doy, sec, alt, g_lat, g_long, lst, f107A, f107, ap, ap_a=None, flags=None)

MSIS Neutral Atmosphere Empircial Model from the surface to lower exosphere.

Parameters:

• year (int) – Year, but has no real effect, more important is doy.

• doy (int) – Day of the year.

• sec (float) – Seconds into the day (UT).

• alt (float) – Altitude in [km].

• g_lat (float) – Geodetic latitude in [degrees N].

• g_long (float) – Geodetic longitude in [degrees E].

• lst (float) – Apparent local solar timei [h].

• f107A (float) – 81 day average of 10.7 cm radio flux (centered on doy) at the actual distance of the Earth from the Sun rather than the radio flux at 1 AU.

• f107 (float) – Daily F10.7 flux for previous day at position of Earth. Like f107A at the actual distance of the Earth from the Sun rather than the radio flux at 1 AU.

• ap (float) – Daily geomagnetic ap index.

• ap_a (list of 7 floats, optional) –

  Array containing the following magnetic values:

  0. daily AP

  1. 3 hr AP index for current time

  2. 3 hr AP index for 3 hrs before current time

  3. 3 hr AP index for 6 hrs before current time

  4. 3 hr AP index for 9 hrs before current time

  5. Average of eight 3 hr AP indicies from 12 to 33 hrs

     prior to current time

  6. Average of eight 3 hr AP indicies from 36 to 57 hrs

     prior to current time

• flags (list of 24 int, optional) –

  Sets the model’s internal switches array. Quote from the NRLMSISE-00 source code: Switches: to turn on and off particular variations use these switches. 0 is off, 1 is on, and 2 is main effects off but cross terms on.

  Standard values are 0 for switch 0 and 1 for switches 1 to 23. The array ‘switches’ needs to be set accordingly by the calling program. The arrays sw and swc are set internally.

  switches[i]:

  0. output in meters and kilograms instead of centimetres and grams

  1. F10.7 effect on mean

  2. time independent

  3. symmetrical annual

  4. symmetrical semiannual

  5. asymmetrical annual

  6. asymmetrical semiannual

  7. diurnal

  8. semidiurnal

  9. daily ap

     [when this is set to -1 (!) the pointer ap_a in struct nrlmsise_input must point to a struct ap_array]

  10. all UT/long effects

  11. longitudinal

  12. UT and mixed UT/long

  13. mixed AP/UT/LONG

  14. terdiurnal

  15. departures from diffusive equilibrium

  16. all TINF var

  17. all TLB var

  18. all TN1 var

  19. all S var

  20. all TN2 var

  21. all NLB var

  22. all TN3 var

  23. turbo scale height var

Returns:

• densities (list) – the NRLMSISE-00 densities:

  • d[0] - HE NUMBER DENSITY(CM-3)

  • d[1] - O NUMBER DENSITY(CM-3)

  • d[2] - N2 NUMBER DENSITY(CM-3)

  • d[3] - O2 NUMBER DENSITY(CM-3)

  • d[4] - AR NUMBER DENSITY(CM-3)

  • d[5] - TOTAL MASS DENSITY(GM/CM3) [includes d[8] in td7d]

  • d[6] - H NUMBER DENSITY(CM-3)

  • d[7] - N NUMBER DENSITY(CM-3)

  • d[8] - Anomalous oxygen NUMBER DENSITY(CM-3)

  O, H, and N are set to zero below 72.5 km

  d[5], TOTAL MASS DENSITY, is NOT the same for subroutines GTD7 and GTD7D SUBROUTINE GTD7 – d[5] is the sum of the mass densities of the species labeled by indices 0-4 and 6-7 in output variable d. This includes He, O, N2, O2, Ar, H, and N but does NOT include anomalous oxygen (species index 8).

• temperatures (list) – the NRLMSISE-00 temperatures:

  • t[0] - EXOSPHERIC TEMPERATURE

  • t[1] - TEMPERATURE AT ALT

  t[0], Exospheric temperature, is set to global average for altitudes below 120 km. The 120 km gradient is left at global average value for altitudes below 72 km.

nrlmsise00._nrlmsise00.gtd7d(*args, **kwargs)

MSIS Neutral Atmosphere Empircial Model from the surface to lower exosphere.

This subroutine provides Effective Total Mass Density for output d[5] which includes contributions from ‘anomalous oxygen’ which can affect satellite drag above 500 km. See ‘returns’ for additional details.

Parameters:

• *args – Same as for gtd7().

• **kwargs – Same as for gtd7().

Returns:

densities, temperatures – See documentation for gtd7(), except for d[5]:

SUBROUTINE GTD7D – d[5] is the ‘effective total mass density for drag’ and is the sum of the mass densities of all species in this model, INCLUDING anomalous oxygen.

Return type:

(list, list)