Santa Barbara DISORT atmospheric radiative Transfer
SBDART
Contents
1. Installation instructions
a) Windows
b) Linux (Ubuntu)
How to run the model ?
2. Shell Scripting to enable loop run
3. DISORT
4. Parameters and their usage
1. Installation Instructions
a) Windows : Copy the files downloaded from website. Use the cmd, command window and
use sbdart.exe command to execute the program. A file named INPUT.dat contains all the
input parameters. If a parameter is not mentioned, then code considers default values for that
parameter
b) Linux : In ubuntu terminal, use the fortran code and compile using gfortran command to
create an executable file. Use the executable file to run the code. A file named INPUT.dat
contains all the input parameters. If a parameter is not mentioned, then code considers
default values for that parameter
2.
Example :
rm -f sbout3
for iday in 90; do
echo "
\$INPUT
idatm=1, wlinf=.3, wlsup=10, iday=$iday, wlinc=.1,alat=13,alon=77,
iout=23,xco2=0.0,xn2=0.0,xo2=0.0,uw=0.0,nzen=10,uzen=0,90,time=4,
\$END" > INPUT.DAT
./sbdartt
while read line
do
echo $line
done<OUTPUT.dat >>day$iday.dat
done
Consider the above shell script . The above code is to be written in a text file and change the
permissions using chmod 755 ****.txt . After that the shell file can be executed using
./***.sh
3. Discrete Ordinates Radiative Transfer Program for a Multi-Layered Plane-Parallel
Medium is a General and versatile plane-parallel radiative transfer program
applicable to problems from the ultraviolet to the radar regions of the
electromagnetic spectrum.
4. Paramters and their usage
Total number of parameters : 75
Other input files are sometimes required by SBDART:
atms.dat
-- atmospheric profile
(see input quantity IDATM)
aerosol.dat -- aerosol information
(see input quantity IAER)
albedo.dat -- spectral surface albedo
(see input quantity ISALB)
filter.dat -- sensor filter function
(see input quantity ISAT)
solar.dat -- solar spectrum
(see input quantity NF)
usrcld.dat -- cloud vertical profile
(see input quantity TCLOUD)
Parameter Parameter
number
Description
Default value Comment/remark
WAVELENGTH LIMITS, FILTER
FUNCTION SPECIFICATION
nf
Solar spectrum selector
isat
Filter function types
wlinf
Lower wavelength limit
0.55
wlsup
Upper wavelength limit
0.55
wlinc
Wavelength increment
0.0
SOLAR GEOMETRY
sza
Solar zenith angle
degree
csza
Cosine of solar zenith angle
-1
degree
saza
Solar azimuth angle
180
degree
iday
Day of the year
10
time
Time of day
16
11
alat
latitude
-64.76
12
alon
longitude
-64.76
13
solfac
Solar distance factor
14
nosct
aerosol scattering mode
SURFACE REFLECTANCE
PROPERTIES
15
isalb
Surface albedo feature
16
albcon
17
sc
1,3*0
MODEL ATMOSPHERES
18
idatm
Atmospheric profiles
19
amix
Weighting factor
20
uw
Integrated column water vapor
-1
21
uo3
Integrated ozone concentration
-1
22
o3trp
Integrated ozone concentration
in troposphere
-1
23
ztrp
Altitude of tropopause
GMT
24
xn2
Vmr of n2
-1
25
xo2
Vmr of o2
-1
26
xch4
Vmr of ch4
-1
27
xn2o
Vmr of n2o
-1
28
xco
Vmr of co
-1
29
xnh3
Vmr of nh3
-1
30
xso2
Vmr of so2
-1
31
xno
Vmr of no
-1
32
xhno3
Vmr of hno3
-1
33
xno2
Vmr of no2
-1
34
xrsc
Sensitivity factor for rayleigh
scattering
35
xo4
Sens. Fctr to adjust oxy absor
36
pbar
Surface pressure
-1
37
zpres
Surface altitude
-1
38
sclh2o
Water vapour scale height
-1
CLOUD PARAMETERS
39
zcloud
Alt of cloud layers
5*0.0
40
tcloud
Optical thickness of cloud layer
5*0.0
41
nre
Cloud drop effective radius
5*8.0
42
imomc
Phase function model used in
cloud layers
43
lwp
Liquid water path
5*0.0
44
rhcld
Relative humidity within cloud
layer
-1
45
krhcld
STRATOSPHERIC AEROSOLS
(LOWTRAN 7 model)
46
jaer
Stratospheric aerosol types
5*0
47
zaer
Alt of stratospheric aerosol
5*0
48
taerst
Optical depth(.55um) of each
stratospheric aerosol layer
5*0
BOUNDARY LAYER
AEROSOLS (BLA)
49
iaer
Boundary layer aerosol type
selector
50
rhaer
Relative humidiity
-1
51
vis
(Horizontal Path) Visibility
(km)at 0.55um due to boundary
layer aerosols
23
52
zbaer
Altitude grid for custom aerosol
vertical profile
50*-1
53
dbaer
Aerosol density at ZBAER
altitude grid points
50*-1
0
F
54
tbaer
Vertical optical depth of
boundary layer aerosols
47*0
55
qbaer
extinction efficiency
----
56
wlbaer
Wavelengths points (um)
47*0
57
wbaer
Single scattering albedo used
with IAER=5
47*0.950
58
gbaer
Asymmetry factor used with
IAER=5
47*0.7
59
pmaer
Legendre moments of the
scattering phase function
940*0
60
abaer
Wavelength (Angstrom model)
exponent used to extrapolate
BLA extinction
efficiency
-1
61
imoma
Controls phase function used
for boundary layer aerosol
62
spowder
63
nothrm
-1
64
kdist
65
zgrid1
three parameters can be used
to change the grid resolution of
the model atmosphere
66
zgrid2
three parameters can be used
to change the grid resolution of
the model atmosphere
30
67
ngrid
three parameters can be used
to change the grid resolution of
the model atmosphere
50
OUTPUT OPTIONS
68
idb
Diagnostic output selector
20*0
69
zout
Altitude of Surface and TOA
0,100
70
iout
Standard output selector
10
DISORT OPTIONS
71
deltam
use delta-m method
72
nstr
number of computational zenith
angles used
73
corint
intensities are correct for deltaM scaling effects
-----
RADIANCE OUTPUT
74
nzen
Number of user zenith angles
75
uzen
User zenith angles
20*-1
76
vzen
User nadir angles
20*90
77
nphi
Number of user azimuth angles
78
phi
User relative azimuth angles
20*-1
RADIATION BOUNDARY
CONDITIONS
79
ibcnd
boundary conditions
80
fisot
intensity of top-boundary
isotropic illumination
81
temis
emissivity of top layer
82
btemp
Surface (skin) temperature in
Kelvin
----
DISORT specific output
83
prnt(k)
Output options
----
x*y means x multiplied by 10 to power of y
