atmositu

Use ITU reference atmospheres

Syntax

[t,p,wvden] = atmositu(h)

[t,p,wvden] = atmositu(___,Name,Value)

atmositu(___)

Description

[t,p,wvden] = atmositu(h) calculates the International Telecommunication Union (ITU) standard atmospheric model and returns the atmospheric temperature t, pressure p, and water-vapor density wvden.

[t,p,wvden] = atmositu(___,Name,Value) returns the atmospheric temperature, pressure, and water-vapor density with additional options specified by one or more name-value pairs. For example, 'LatitudeModel','High' specifies a reference model for latitudes greater than 45°.

atmositu(___) with no output arguments plots:

• Atmospheric temperature t versus altitude in linear scale

• Atmospheric pressure p versus altitude in logarithmic x-scale

• Atmospheric water-vapor density wvden versus altitude in logarithmic x-scale

Examples

Compute and Visualize Atmospheric Profiles

Compute the atmospheric temperature, pressure, and water-vapor density for a mid-latitude area during winter. Specify an altitude range between 2 km and 88 km.

h = (2:88).*1e3;

[t,p,wvden] = atmositu(h,'LatitudeModel','Mid','Season','Winter')

t = 1×87

  264.7771  260.2759  255.4229  250.2181  244.6615  238.7531  232.4929  225.8809  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  218.0000  221.3571  224.7142  228.0713  231.4284  234.7855  238.1426  241.4997  244.8568  248.2139  251.5710  254.9281  258.2852  261.6423  265.0000  265.0000  265.0000  265.0000  265.0000

p = 1×87

  789.5947  689.4528  598.9723  518.1532  446.9955  385.4992  333.6643  291.4908  258.9787  223.5748  193.0107  166.6250  143.8464  124.1817  107.2053   92.5497   79.8976   68.9751   59.5458   51.4055   44.3781   38.3113   33.0739   28.5525   24.6492   21.2795   18.3705   15.8591   13.6911   11.8194   10.2037    8.8088    7.6045    6.5650    5.6675    4.8927    4.2238    3.6464    3.1479    2.7176    2.3461    2.0254    1.7485    1.5095    1.3031    1.1250    0.9712    0.8384    0.7238    0.6248

wvden = 1×87

    1.7601    1.1320    0.6829    0.3875    0.2074    0.1049    0.0503    0.0230    0.0100         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0         0

Plot the atmospheric temperature, pressure, and water-vapor density profiles for the same model.

atmositu(h,'Latitude','Mid','Season','Winter')

Input Arguments

h — Geometric heights

row vector

Geometric heights corresponding to the altitude above mean sea level (MSL) in meters, specified as a row vector. The atmositu function returns NaNs for any input value outside of the interval [0,100].

Data Types: double

Name-Value Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside quotes. You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

Example: atmositu(h,'LatitudeModel','Mid','Season','Winter') specifies the mid-latitude model during winter.

VaporDensity — Standard ground-level water-vapor density

7.5 (default) | scalar

Standard ground-level water-vapor density in g/m³, specified as a scalar. VaporDensity applies only when LatitudeModel is set to the default 'Standard' model.

Data Types: double

ScaleHeight — Scale height

2000 (default) | scalar

Scale height in meters, specified as a scalar. ScaleHeightapplies only when LatitudeModel is set to the default 'Standard' model. For a dry atmosphere, set ScaleHeight to 6000.

Data Types: double

LatitudeModel — Reference latitude model

'Standard' (default) | 'Low' | 'Mid' | 'High'

Reference latitude model, specified as:

• 'Standard' — This is the Mean Annual Global Reference Atmosphere (MAGRA) model that reflects the mean annual temperature and pressure averaged across the world.

• 'Low' — Use this model for latitudes lower than 22°, with little seasonal variation.

• 'Mid' — Use this model for latitudes between 22° and 45° that have seasonal profiles for summer and winter. You can specify a seasonal profile using the Season name-value pair.

• 'High' — Use this model for latitudes greater than 45° that have seasonal profiles for summer and winter. You can specify a seasonal profile using the Season name-value pair.

Season — Seasonal profile

'Summer' (default) | 'Winter'

Seasonal profile, specified as 'Summer' or 'Winter'. This argument is valid only when LatitudeModel is set to 'Mid' or 'High'.

Output Arguments

t — Temperature

row vector

Atmospheric temperature in Kelvin, returned as a row vector.

p — Atmospheric pressure

row vector

Atmospheric pressure in hectopascals, returned as a row vector.

wvden — Water-vapor density

row vector

Atmospheric water-vapor density in g/m³, returned as a row vector.

References

[1] International Telecommunication Union (ITU). "Reference Standard Atmospheres". Recommendation ITU-R P.835-6, P Series, Radiowave Propagation, December 2017.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.