7.1.3 Models of the Earth’s atmosphere

7.1.3.1 NRLMSISE-00 model

The NRL Mass Spectrometer, Incoherent Scatter Radar Extended Model (NRLMSISE-00) model [RN.4] describes the neutral temperature and species densities in Earth's atmosphere.

It is based on a very large underlying set of supporting data from satellites, rockets and radars, with extensive temporal and spatial distribution. It has been extensively tested by the global scientific community against experimental data. The model has a flexible mathematical formulation.

It is valid for use from ground level to the exosphere.

Two indices are used in this model:

• F10.7 (both the daily value of the previous day and the 81-day average centred on the input day),

• A_p (daily value).

7.1.3.2 JB-2006 model

The Jacchia-Bowman 2006 (JB-2006) model [RN.5] also describes the neutral temperature and the total density in Earth’s thermosphere and exosphere. Its new features, described in Annex G, lead to a better and more accurate model representation of the mean total density, compared with previous models, including the NRLMSISE-00.

It is valid for use from an altitude of 120 km to the exosphere.

Four indices are used in this model:

• F10.7 (both tabular value one day earlier and the 81-day average centred on the input time),

• S10.7 (both tabular value one day earlier and the 81-day average centred on the input time),

• M10.7 (both tabular value five days earlier and the 81-day average centred on the input time),

• A_p (tabular value 6,7 hours earlier).