Location of the atmospheric data file.
atmosphere_file file
The file must have at least three columns containing the altitude,
pressure, and temperature. Missing profiles are filled with 0 (e.g., if you did not specify
the ozone profile, there will be no ozone absorption!), with exception of the air density which
is calculated from pressure and temperature. Other traces gases may be set by dens_file.
The columns are interpreted as follows:
- 1
-
Altitude above sea level in km
- 2
-
Pressure in hPa
- 3
-
Temperature in K
- 4
-
air density in cm
- 5
-
Ozone density in cm
- 6
-
Oxygen density in cm
- 7
-
Water vapour density in cm
- 8
-
CO2 density in cm
- 9
-
NO2 density in cm
The atmosphere is specified
top-down, that is, the top level is the first line in the file, the bottom
(surface) level the last line. All properties refer to model level z,
not to model layer. It is important that the correct units are
used, otherwise unpredictable results are guaranteed.
Comments start with #. Empty lines are ignored. Please note that there
is some redundancy: For air as an ideal gas the density , can be
calulated from pressure and temperature,
. uvspec will check
if this relation is fulfilled and will stop if it is not.
libRadtran provides the six standard atmospheres by Anderson1986:
- afglt
-
Tropical (tropics)
- afglms
-
Midlatitude Summer (midlatitude_summer)
- afglmw
-
Midlatitude Winter (midlatitude_winter)
- afglss
-
Subarctic Summer (subarctic_summer)
- afglsw
-
Subarctic Winter (subarctic_winter)
- afglus
-
U.S. Standard (US-standard)
which may be chosen by for example
atmosphere_file tropics
or by specifying the the full file name. These atmosphere files are found in
data/atmmod.
If no atmosphere_file is defined, uvspec will automatically select one.
If the information time, latitude and longitude are provided in
the input file uvspec will choose from the first 5 files, otherwise it takes
the U.S. Standard atmosphere.