ISO 14222:2013

Space environment (natural and artificial) — Earth upper atmosphere

ISO 14222:2013 specifies the structure of Earth's atmosphere above 120 km, provides accepted empirical models that can specify the details of the atmosphere, and uses annexes to describe the details of those models. Its purpose is to create a standard method for specifying Earth atmosphere properties (densities, etc.) in the low Earth orbit regime for space systems and materials users.

Environnement spatial (naturel et artificiel) — Haute atmosphère terrestre

General Information

• Status: Withdrawn
• Publication Date: 15-Sep-2013
• ICS: 49.140 - Space systems and operations
• Technical Committee: ISO/TC 20/SC 14 - Space systems and operations
• Drafting Committee: ISO/TC 20/SC 14/WG 4 - Space environment (natural and artificial)
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 23-Mar-2022

Relations

• Revised: ISO 14222:2022 - Space environment (natural and artificial) — Earth's atmosphere from ground level upward
• Effective Date: 23-Apr-2020

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 14222
First edition
2013-09-15
Space environment (natural and
artificial) — Earth upper atmosphere
Environnement spatial (naturel et artificiel) — Haute atmosphère
terrestre
Reference number
ISO 14222:2013(E)
ISO 2013
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ISO 14222:2013(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2013

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ISO 14222:2013(E)
Contents  Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2  Terms and definitions ..................................................................................................................................................................................... 1

3  Symbols and abbreviated terms ........................................................................................................................................................... 3

4  General concept and assumptions ..................................................................................................................................................... 3

4.1 Earth atmosphere model use...................................................................................................................................................... 3

4.2 Earth wind model use ....................................................................................................................................................................... 4

4.3 Robustness of standard ................................................................................................................................................................... 4

Annex A (informative) Neutral atmospheres ............................................................................................................................................... 5

Annex B (informative) Natural electromagnetic radiation and indices ........................................................................25

Bibliography .............................................................................................................................................................................................................................38

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ISO 14222:2013(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directives

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any

patent rights identified during the development of the document will be in the Introduction and/or on

the ISO list of patent declarations received. www.iso.org/patents

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

The committee responsible for this document is ISO/TC 20, Aircraft and space vehicles, Subcommittee

SC 14, Space systems and operations.
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ISO 14222:2013(E)
Introduction

This International Standard provides guidelines for determining the Earth’s upper atmosphere

properties (above 120 km). A good knowledge of temperature, total density, concentrations of gas

constituents, and pressure is important for many space missions exploiting the low-earth orbit (LEO)

regime below approximately 2 500 km altitude. Aerodynamic forces on the spacecraft, due to the

orbital motion of a satellite through a rarefied gas, which itself can have variable high velocity winds,

are important for planning satellite lifetime, maintenance of orbits, collision avoidance maneuvering

and debris monitoring, sizing the necessary propulsion system, design of attitude control system, and

estimating the peak accelerations and torques imposed on sensitive payloads. Surface corrosion effects

due to the impact of large fluxes of atomic oxygen are assessed to predict the degradation of a wide

range of sensitive coatings of spacecraft and instruments. The reactions of atomic oxygen around a

spacecraft can also lead to intense “vehicle glow”.

The structure of Earth’s upper atmosphere, accepted empirical models that can specify the details of

the atmosphere, and the details of those models (Annex A) are included in this International Standard.

Annex B provides a detailed description of the Neutral Electromagnetic Radiation and Indices.

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INTERNATIONAL STANDARD  ISO 14222:2013(E)
Space environment (natural and artificial) — Earth
upper atmosphere
1 Scope

This International Standard specifies the structure of Earth’s atmosphere above 120 km, provides

accepted empirical models that can specify the details of the atmosphere, and uses annexes to describe

the details of those models. Its purpose is to create a standard method for specifying Earth atmosphere

properties (densities, etc.) in the low Earth orbit regime for space systems and materials users.

2  Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1
homosphere

region of the atmosphere that is well mixed, i.e. the major species concentrations are independent of

height and location

Note 1 to entry: This region extends from 0 to ~100 km, and includes the temperature-defined regions of

the troposphere (surface up to ~8 - 15 km altitude), the stratosphere (~10 - 12 km up to 50 km altitude ), the

mesosphere (~50 km up to about 90 km altitude), and the lowest part of the thermosphere.

2.2
heterosphere

portion of the atmosphere, above ~125 km, where diffusive separation of species dominates and

atmospheric composition depends on height
2.3
thermosphere

region of the atmosphere between the temperature minimum at the mesopause (~90 km) and the

altitude where the vertical scale height is approximately equal to the mean free path (400 - 600 km)

altitude, depending on solar and geomagnetic activity levels
2.4
exosphere
region of the atmosphere that extends from the top of the thermosphere outward
2.5
NRLMSISE-00

Naval Research Labatory Mass Spectrometer, Incoherent Scatter Radar Extended Model

model that describes the neutral temperature and species densities in Earth’s atmosphere

Note 1 to entry: 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 against experimental data by the

international scientific community. The model has a flexible mathematical formulation.

Note 2 to entry: It is valid for use from ground level to the exosphere. Two indices are used in this model: F

10.7

(both the daily solar flux value of the previous day and the 81-day average centred on the input day) and A

(geomagnetic daily value).
[1]
Note 3 to entry: See Reference
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ISO 14222:2013(E)
2.6
JB2008
Jacchia-Bowman 2008 Model

model that describes the neutral temperature and the total density in Earth’s thermosphere and exosphere

Note 1 to entry: Its new features lead to a better and more accurate model representation of the mean total

density compared with previous models, including the NRLMSISE-00.

Note 2 to entry: It is valid for use from an altitude of 120 km to 2 500 km in the exosphere. Four solar indices and

two geomagnetic activity indices are used in this model: F (both tabular value one day earlier and the 81-day

10.7

average centred on the input time); S (both tabular value one day earlier and the 81-day average centred on

10.7

the input time); M (both tabular value five days earlier and the 81-day average centred on the input time); Y

10.7 10.7

(both tabular value five days earlier and the 81-day average centred on the input time); a (3 hour tabular value);

and Dst (converted and input as a dTc temperature change tabular value on the input time).

[2]
Note 3 to entry: See Reference
2.7
HWM07
Horizontal Wind Model

Comprehensive empirical global model of horizontal winds in the mesosphere and thermosphere

(middle and upper atmosphere).

Note 1 to entry: Reference values for the a index needed as input for the wind model are given in Annex A.

Note 2 to entry: HWM07 does not include a dependence on solar EUV irradiance. Solar cycle effects on thermospheric

winds are generally small during the daytime, but can exceed 20 m/s at night.

Note 3 to entry: HWM07 thermospheric winds at high geomagnetic latitudes during geomagnetically quiet

periods should be treated cautiously.
[3]
Note 4 to entry: See Reference
2.8
Earth GRAM 2010

Earth Global Reference Atmosphere Models (latest version is GRAM 2010) produced on behalf of NASA,

that describe the terrestrial atmosphere from ground level upward for operational purposes

Note 1 to entry: GRAM 2010 provides a global reference terrestrial atmosphere model based on a combination of

empirically based models that represent different altitude ranges up to ~120 km. The upper atmosphere section

above ~120 km has the option of three different atmosphere models, the Marshall Thermosphere (MET-07),

the Naval Research Laboratory Mass Spectrometer, Incoherent Scatter Radar Extended (NRLMISE-00) and the

Jacchia-Bowman (JB-2008) model. In addition the NRL1993 Harmonic Wind Model (HWM-93) is included for use

in conjunction with the NRLMISE-00.

Note 2 to entry: These models are available via license from NASA to qualified users and provide usability and

information quality similar to that of the NRLMSISE-00 Model. Earth GRAM 2007 includes options for NRLMSIS-00,

HMW-93, and JB2006 models.
[4]
Note 3 to entry: See Reference .
2.9
DTM-2009
Drag Temperature Model 2009

model that describes the neutral temperature and major and some minor species densities in Earth’s

atmosphere between an altitude of 120 km to approximately 1 500 km

Note 1 to entry: DTM-2009 is based on a large database going back to the early ‘70s, essentially the same that was

used for NRLMSISE-00 except for the radar data. In addition, high-resolution CHAMP and GRACE accelerometer-

inferred densities are assimilated in DTM-2009.

Note 2 to entry: DTM-2009 is valid from an altitude of 120 km to approximately 1 500 km in the exosphere. Two

indices are used in this model: F solar flux (both daily solar flux of the previous day and the 81-day average

10.7

centred on the input day) and Kp (3-hour value delayed by three hours, and the average of the last 24 hours).

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Note 3 to entry: The DTM model codes (DTM-94, DTM-2000, DTM-2009) are available for download on the ATMOP

project website .
[5]
Note 4 to entry: See Reference
3  Symbols and abbreviated terms
a the 3-hour planetary geomagnetic index, in units nT
A the daily planetary geomagnetic index, in units nT
CIRA COSPAR International Reference Atmosphere
COSPAR Committee on Space Research
Dst the hourly disturbance storm time ring current index, in units nT
-22 -2
F the F solar proxy, in units of solar flux, × 10 W m
10 10.7
-22 -2
M the M solar proxy, in units of solar flux, × 10 W m
10 10.7
-22 -2
S the S solar index, in units of solar flux, × 10 W m
10 10.7
URSI International Union of Radio Science
-22 -2
Y the Y solar index, in units of solar flux, ×10 W m
10 10.7
4  General concept and assumptions
4.1  Earth atmosphere model use
[1]

The NRLMSISE-00 model should be used for calculating both the neutral temperature and the detailed

composition of the atmosphere.
[2]

The JB2008 model should be used for calculating the total atmospheric density above an altitude of

120 km, for example as used in determining satellite drag in LEO.
[4]

The Earth-GRAM model 2010 may be used for calculating the total atmospheric density above an

altitude of 120 km, for example as used in determining satellite drag in LEO.
[5]

The DTM-2009 may be used for calculating the total atmospheric density above an altitude of 120 km,

for example as used in determining satellite drag in LEO.

For altitudes below 120 km, NRLMSISE-00 or Earth GRAM 2010 should be used for calculating the

total air density.

NOTE This usage follows the advice of the CIRA Working Group, sponsored by COSPAR and URSI, and

following the resolution of the Assembly of COSPAR in Montreal in July 2008.
4.1.1  Application guidelines

a) The NRLMSISE-00 model for species densities should not be mixed with the JB2008, Earth GRAM

2010 or DTM-2009 model for total density.

b) For worst-case high solar activity results and analysis periods not exceeding 1 week, high daily

short-term values given in Annex A should be used as input for daily activity together with the high

long-term values for the 81-day average activity.
1) http://www.atmop.eu/downloads.php
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ISO 14222:2013(E)

c) For analysis periods longer than 1 week the long-term solar activities given in Annex A should be

used as input for both the daily and the 81-day averaged values.

d) For analysis periods longer than 1 week and conditions specified in Annex A, the daily and 81-day

averaged solar activities given in Annex A should be used.

e) Short-term daily high solar activity values should not be used together with low or moderate long-

term solar activity values.

NOTE 1 The JB2008, NRLMSISE-00, and Earth GRAM 2010 models can only predict large scale and slow

variations in the order of 1 000 km (given by the highest harmonic component) and 3 hours. Spacecrafts can

encounter density variations with smaller temporal and spatial scales partly since they are in motion (for

example, +100% or -50% in 30 s), and partly because smaller-scale disturbances certainly occur during periods

of disturbed geomagnetic activity.

NOTE 2 Reference values for the key indices needed as inputs for the atmosphere models are given in Annex A.

NOTE 3 The F 81-day average solar activity can also be estimated by averaging three successive monthly

10.7
predicted values.
[1] [2]

NOTE 4 Information on density model uncertainties can be found in Annex A and in References and.

NOTE 5 For high solar activities, the atmosphere models only give realistic results if high short-term values are

combined with high 81-day averaged values.

NOTE 6 High Dst values can be used corresponding to low, moderate or high solar activities.

4.2  Earth wind model use
[3]
The HWM07 wind model should be used.

High daily short-term solar activity values should be used as worst-case for the daily activity but the 81-

day average activity should not exceed the high long-term value.

NOTE 1 Reference values for the key indices needed as inputs for the wind model are given in Annex A.

NOTE 2 The F 81-day average solar activity can also be estimated by averaging three successive monthly

10.7
predicted values as given in Annex A.

NOTE 3 The use of the HWM07 model at high geomagnetic latitudes and for disturbed geomagnetic periods

necessitates caution in the interpretation of model results.
4.3  Robustness of standard

The Earth’s upper atmosphere models described in this International Standard are intended to be

adapted and improved over time as the international scientific community obtains and assesses high

quality data on the upper atmosphere. Therefore, the users of the models described should ensure they

are utilizing the latest version of the respective models.
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ISO 14222:2013(E)
Annex A
(informative)
Neutral atmospheres
A.1 Structure of the Earth’s atmosphere

The Earth’s atmosphere can be classified into different regions based on temperature, composition, or

collision rates among atoms and molecules. For the purposes of the document, the atmosphere is broadly

divided into three regimes based on all three properties, as shown in Figure A.1:

i) The homosphere is the portion of the atmosphere that is well mixed, i.e. the major species

concentrations are independent of height and location. This region extends from 0 to ~100 km, and

includes the temperature-defined regions of the troposphere (surface up to ~8 - 15 km altitude), the

stratosphere (~10 - 12 km up to 50 km altitude ), the mesosphere (~50 km up to about 90 km altitude),

and part of the thermosphere.

ii) The thermosphere is the region between the temperature minimum at the mesopause (~90 km) and

the altitude where the vertical scale height is approximately equal to the mean free path (400 - 600 km

altitude, depending on solar and geomagnetic activity levels).
iii) The exosphere extends from the top of the thermosphere into space.

In practice, the boundaries between these regions, whether determined in altitude or in a pressure co-

ordinate system, vary with solar, seasonal, latitudinal, and other conditions.

Due to winds and turbulent mixing the homosphere has a nearly uniform composition of about 78,1%

N , 20,9% O , and 0,9% Ar. The temperature profile of the thermosphere increases rapidly above a

2 2

minimum of ~180 K at the mesopause, then gradually relaxes above ~200 km to an asymptotic value

known as the exospheric temperature.
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ISO 14222:2013(E)
Figure A.1 — Representative temperature profile of the Earth’s atmosphere
A.2 Development of models of the Earth’s atmosphere

A “Standard Atmosphere” is defined as a vertical distribution of atmospheric temperature, pressure,

and density, which by international agreement is taken to be representative of the Earth’s atmosphere.

The first “Standard Atmospheres” established by international agreement were developed in the 1920s

primarily for purposes of pressure altimeter calibrations, aircraft performance calculations, aircraft

and rocket design, ballistic tables, etc. Later, some countries, notably the United States, also developed

and published “Standard Atmospheres”. The term “Reference Atmosphere” is used to identify vertical

descriptions of the atmosphere for specific geographical locations or globally. These were developed

by organizations for specific applications, especially as the aerospace industry began to mature after

World War II. The term “Standard Atmosphere” has in recent years also been used by national and

international organizations to describe vertical descriptions of atmospheric trace constituents, the

ionosphere, atomic oxygen, aerosols, ozone, winds, water vapour, planetary atmospheres, etc.

[6]

Currently some of the most commonly used Standard and Reference Atmospheres include: the ISO

Standard Atmosphere 1975, 1982; the U. S. Standard Atmosphere Supplements, 1962, 1966, 1976; the

COSPAR International Reference Atmosphere (CIRA), 1986 (previously issued as CIRA 1961, CIRA 1965

and CIRA 1972); the NASA/MSFC Global Reference Atmosphere Model, Earth GRAM 2010 (previously

issued as GRAM-86, GRAM-88, GRAM-90, GRAM-95, GRAM-99 and GRAM-07); the NRLMSISE-00

Thermospheric Model, 2000 (previously issued as MSIS-77, -83, -86 and MSISE-90); and most recently

the JB2006 and JB2008 density models.
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ISO 14222:2013(E)
A.3 NRLMSISE-00 and JB2008 — Additional information

A.3.1 The Mass Spectrometer and Incoherent Scatter (MSIS) series of models developed be-

tween 1977 and 1990 are used extensively by the scientific community for their superior de-

scription of neutral composition. The models utilized atmospheric composition and temperature

data from instrumented satellites and ground-based radars. The initial MSIS 1977 model utilized

a Bates-Walker temperature profile (which is analytically integrable to obtain density), and al-

lowed the density at 120 km to vary with local time and other geophysical parameters to fit the

measurements. The temperature and density parameters describing the vertical profile were ex-

panded in terms of spherical harmonics to represent geographic variations. Subsequent versions

of the model include the longitude variations, a refined geomagnetic storm effect, improved high

latitude, high solar flux data, and an extension of the lower boundary down to sea level.

The NRLMSISE-00 model represents atmospheric composition, temperature, and total mass density from

the ground to the exosphere. Its formulation imposes a physical constraint of hydrostatic equilibrium

to produce self-consistent estimates of temperature and density. NRLMSISE-00 includes the following

enhancements compared to MSISE-90:
i) drag data based on orbit determination,
ii) more recent accelerometer data sets,

iii) new temperature data derived from Millstone Hill and Arecibo incoherent scatter radar observations,

iv) observations of O by the Solar Maximum Mission (SMM), based on solar ultraviolet occultation,

v) a new species, “anomalous oxygen,” primarily for drag estimation, allows for appreciable O+ and hot

atomic oxygen contributions to the total mass density at high altitudes.

A.3.2 The Jacchia-Bowman density (JB2008) model is based on the Jacchia model heritage.

It includes two key novel features. Firstly, there is a new formulation concerning the semi-

annual density variation observed in the thermosphere, but not previously included in any of

the semi-empirical atmospheric models. Secondly, there is a new formulation of solar indices,

relating more realistically the dependence of heat and energy inputs from the solar radiation

to specific altitude regions and heating processes within the upper atmosphere. The Dst index

(equatorial magnetic perturbation) is used in JB2008 as the index representing the geomagnet-

ic activity response. JB2008 inserts the improved J70 temperature formulations into the CIRA

1972 model to permit integrating the diffusion equation at every point rather than relying on

look-up tables (the integration must be done numerically, in contrast to the analytically integra-

ble Bates-Walker temperature formulation used in MSIS). In order to optimally represent the

orbit-derived mass density data on which JB2008 is based, the model formulation sacrifices the

physical constraint of hydrostatic equilibrium since it does not include all physical processes

that may actually be present in thermosphere affecting temperatures and densities.

A.4 The series of GRAM atmospheric models

The National Aeronautics and Space Administration’s NASA/MSFC Global Reference Atmospheric Model

version 2007 (Earth GRAM 2010) is a product of the Natural Environments Branch, NASA Marshal

Space Flight Center. These models are available via license to qualified users and provide usability and

information quality similar to that of the NRLMSISE-00 Model. Like the previous versions of GRAM, the

model provides estimates of means and standard deviations for atmospheric parameters such as density,

temperature, and winds, for any month, at any altitude and location within the Earth’s atmosphere. GRAM

can also provide profiles of statistically-realistic variations (i.e., with Dryden energy spectral density)

for any of these parameters along computed or specified trajectory. This perturbation feature makes

GRAM especially useful for Monte-Carlo dispersion analyses of guidance and control systems, thermal

protection systems, and similar applications. GRAM has found many uses, both inside and outside

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ISO 14222:2013(E)

the NASA community. Most of these applications rely on GRAM’s perturbation modeling capability

for Monte-Carlo dispersion analyses. Some of these applications have included operational support

for Shuttle entry, flight simulation software for X-33 and other vehicles, entry trajectory and landing

dispersion analyses for the Stardust and Genesis missions, planning for aerocapture and aerobraking

for Earth-return from lunar and Mars missions, six-degree-of-freedom entry dispersion analysis for the

Multiple Experiment Transporter to Earth Orbit and Return (METEOR) system, and more recently the

Crew Exploration Vehicle (CEV). Earth GRAM 2010 retains the capability of the previous version but

also contains several new features. The thermosphere has been updated with the new Air Force JB2008

model, while the user still has the option to select the NASA Marshall Engineering Thermosphere (MET)

model or the Naval Research Laboratory (NRL) Mass Spectrometer, Incoherent Scatter (MSIS) Radar

Extended Model.
A.5 Atmosphere model uncertainties and limitations

For mean activity conditions, the estimated uncertainty of the NRLMSISE-00 species density is 15%. For

short-term and local-scale variations, the estimated uncertainty of the NRLMSISE-00 species density is

100 %. Within the homosphere (below 90 km), the uncertainty is below 5 %. The Earth GRAM 2010 has

a similar uncertainty within the homosphere.

For mean activity conditions, the estimated standard uncertainty of the JB2008 total density within

the thermosphere is in the order of order 10 % (depending on altitude). For extreme conditions (very

high solar or geomagnetic activities), this uncertainty can considerably increase due to the lack of

corresponding measurement data. The total density can have +/- 100 % variation at 400 - 500 km for

some activities and locations.

It should be noted that the models’ accuracy of prediction of atmospheric density and other parameters is

limited by the complex behaviour of the atmosphere, and the causes of variability. While certain aspects

of atmospheric variability are more or less deterministic, meteorological variations of the homosphere

are difficult to predict more than 3 - 5 days in advance, and yet have effects on the thermosphere. In

the thermosphere, the response to varying solar and geomagnetic activity is complex, particularly with

respect to the latter. Upper atmosphere density models can be used for prediction of future orbital

lifetime, either to determine the orbital altitude insertions to ensure a given lifetime, or to estimate

energy requirements for maintaining a particular orbit, for a particular spacecraft/satellite. When the

sun is active, the primary influence on the accuracy of a model’s density output will be the accuracy of

the future predictions of solar and geomagnetic activity used as inputs, rather than the accuracy of the

specific model in representing the density versus altitude as a function of solar and geomagnetic activity.

A.6 HWM07 additional information

The HWM series of models empirically represent the horizontal neutral wind in the atmosphere, using

a truncated set of vector spherical harmonics. The first edition of the model released in 1987 (HWM87)

was intended for winds above 220 km. With the inclusion of wind data from ground-based incoherent

scatter radar, MF/Meteor radar data, and Fabry-Perot optical interferometers, HWM90 was extended

down to 100 km. HWM93 extended the model down to the ground. HWM07 is the most recent version

of the HWM, and includes substantial new space-based data obtained since the early 1990s. Solar

cycle variations are included in the earlier models, but they are found to be small and not always very

clearly delineated by the current data; HWM07 does not depend on solar activity. HWM07 significantly

improves the model’s reliability in the lower ther
...