/INPE-atmosphere-models

Fortran code for various atmosphere modes from http://www.dem.inpe.br/~val/atmod/default.html

Primary LanguageFortranOtherNOASSERTION

A (huge) collection of interchangeable empirical models to compute the thermosphere density, temperature and composition

Description

Thermosphere models are usually employed in space activities such as mission planning and analysis, orbit determination, attitude control design, maneuvering planning, fuel estimation and orbit decay studies, among others.

The Orbital Dynamics group of INPE coded during the 80’s several thermospheric computer programs in FORTRAN. Those models were based on Jacchia works (70 and 77) and their analytical versions, since Jacchia assumed numeric integration of the diffusion equation in order to compute density and composition as function of height. Numeric integration normally demands computing time, and therefore analytical means “fast” in this sense.

Presently there is a set of 5 thermospheric models:

  • Jacchia 70 (in fact it is almost the same as the 64 model)
  • Jacchia-Roberts
  • Jacchia 77
  • LaFontaine-Hughes
  • Jacchia-Lineberry (77 model)

All these programs are interchangeable, which means that any model, can be easily changed to any other. Of course there are several models not included in this list, but, with few exceptions, they do not satisfy the requirement of "interchangeability" since they need different input data, like, for instance, the Jacchia-Bowman JB2006 and JB2008 models (Bowman et al. 2008a, 2008b), which considers the effect of solar UV radiation.

The interchangeable models present 3 entry points:

  • Static profile (function of the exospheric temperature and height)
  • Static density (same as static profile, but function of solar flux F10.7 and geomagnetic activity besides height).
  • Dynamic model.

In order to make it easy to remember and to exchange between models, they were respectively named as:

  • xmowei
  • xsmade
  • xsdamo

where x can be “j” for Jacchia 70, “r” for Robert’s analytical version of Jacchia 70, “i” for Jacchia 77 model (numerical integration), “a” for the analytical version from LaFontaine and Hughes of Jacchia’s 77, and “p” for the Lineberry polynomial analytical version of Jacchia’s 77. “mowei” stands for MOecular WEIght, since the static profile produces mainly the molecular weight as function of height. “smade” means Static Model for Atmospheric DEnsity, and finally “sdamo” is an acronym for Static and Dynamic Atmospheric MOdel, as seem in Table 1.

Table 1 - Profile, Static and Dynamic functions


 Static profile Static density Dynamic model
Jacchia 70 jmowei jsmade jsdamo
Jacchia-Roberts rmowei rsmade rsdamo
Jacchia 77 imowei ismade isdamo
LaFontaine-Hughes amowei asmade asdamo
Jacchia-Lineberry (77 model) pmowei psmade psdamo

References