pybsm.utils.load_database_atmosphere_no_interp

pybsm.utils.load_database_atmosphere_no_interp(*, altitude: float, ground_range: float, ihaze: int) → ndarray

Loads a precalculated MODTRAN 5.2.1 Tape 7 atmosphere over a wavelength range of 0.3 to 14 micrometers.

All screnario details are in ‘atmosphere_README.txt’. NOTE: the _no_interp suffix was added for version 0.2. See pybsm.load_database_atmosphere for more information.

Parameters:

  • altitude – sensor height above ground level in meters. The database includes the following altitude options: 2 32.55 75 150 225 500 meters, 1000 to 12000 in 1000 meter steps, and 14000 to 20000 in 2000 meter steps, 24500 meters

  • ground_range – distance on the ground between the target and sensor in meters. The following ground ranges are included in the database at each altitude until the ground range exceeds the distance to the spherical earth horizon: 0 100 500 1000 to 20000 in 1000 meter steps, 22000 to 80000 in 2000 m steps, and 85000 to 300000 in 5000 meter steps.

  • ihaze – MODTRAN code for visibility, valid options are ihaze = 1 (Rural extinction with 23 km visibility) or ihaze = 2 (Rural extinction with 5 km visibility)

Returns:

atm[:,0]:

wavelengths from .3 to 14 x 10^-6 m in 0.01x10^-6 m steps

atm[:,1]:

(TRANS) total transmission through the defined path.

atm[:,2]:

(PTH THRML) radiance component due to atmospheric emission and scattering received at the observer.

atm[:,3]:

(SURF EMIS) component of radiance due to surface emission received at the observer.

atm[:,4]:

(SOL SCAT) component of scattered solar radiance received at the observer.

atm[:,5]:

(GRND RFLT) is the total solar flux impingent on the ground and reflected directly to the sensor from the ground. (direct radiance + diffuse radiance) * surface reflectance

NOTE:

units for columns 1 through 5 are in radiance W/(sr m^2 m)