def test_userhoriz():
c1 = {
'zmdl': 0.3,
'h1': 0.3,
'range_km': 1.,
'wlshort': 200.,
'wllong': 30000.,
'wlstep': 20.,
}
atmos = {
'p': 949.,
't': 283.8,
'wmol': [93.96, 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.]
}
c1.update(atmos)
TR = lowtran.userhoriztrans(c1)
assert TR.wavelength_nm[[0, -1]].values == approx((30303.03, 200),
rel=0.001)
assert TR['transmission'][0, [1000, 1200],
0].values == approx([0.982909, 0.9645],
rel=0.001)
def calculate_modern_transparency(co2: float,
temp: float,
relative_humidity: float,
height: float,
dist: float,
pressure: float = 949.0) -> float:
"""
Calculate the transparency of the atmosphere using LOWTRAN, a modern
climate calculation model and tool.
:param co2:
The co2 in the atmosphere at the chosen height in ppmv
:param temp:
The temperature of the atmosphere at the chosen height in Kelvin
:param relative_humidity:
The relative humidity of the atmosphere at the chosen height
:param height:
The altitude at which the radiation is traveling, in km
:param dist:
The distance the radiation travels through the atmosphere, in km
:param pressure:
Optional parameter. The pressure of the atmosphere in millibars.
Defaults to the Lowtran default of 949.0 if not explicitly specified.
"""
h2o = calculate_water_vapor(temp, relative_humidity)
p = calculate_mean_path(co2, h2o)
# convert to ppmv
adjusted_co2 = co2 * p * 300
# convert to ppmv from g/m^3
# adjusted_h2o = h2o * p * 10 * 1000 * .082057338 * temp / 18.01528
# Dufresne's h2o adjustment
adjusted_h2o = h2o * p * 20
parameters = {
'h1':
height,
'zmdl':
height,
'range_km':
dist,
'wlshort':
200,
'wllong':
20000,
'wlstep':
200,
'p':
pressure,
't':
temp,
'wmol':
[adjusted_h2o, adjusted_co2, 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.]
}
result = userhoriztrans(parameters)
return float(result['transmission'].mean())
def main():
p = ArgumentParser(description='Lowtran 7 interface')
p.add_argument('-z',
'--obsalt',
help='altitude of bother observers on horizontal path [km]',
type=float,
default=0.3)
p.add_argument('-r',
'--range_km',
help='range between observers on horizontal path [km]',
type=float,
default=1.0)
p.add_argument(
'-a',
'--zenang',
help='zenith angle [deg] can be single value or list of values',
type=float,
default=0.)
p.add_argument('-s',
'--short',
help='shortest wavelength nm ',
type=float,
default=200)
p.add_argument('-l',
'--long',
help='longest wavelength nm ',
type=float,
default=30000)
p.add_argument('-step',
help='wavelength step size cm^-1',
type=float,
default=20)
P = p.parse_args()
c1 = {
'zmdl': P.obsalt,
'h1': P.obsalt,
'range_km': P.range_km,
'wlshort': P.short,
'wllong': P.long,
'wlstep': P.step,
}
atmos = {
'p': 949.,
't': 283.8,
'wmol': [93.96, 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.]
}
c1.update(atmos)
TR = lowtran.userhoriztrans(c1).squeeze()
plothoriz(TR, c1)
show()
def test_userfail():
vlim = (200, 30000)
c1 = {'zmdl': 0.3,
'h1': 0.3,
'range_km': 1.,
'wlnmlim': vlim,
}
TR = lowtran.userhoriztrans(c1)
assert np.isnan(TR['transmission']).all()
def test_userfail():
c1 = {'zmdl': 0.3,
'h1': 0.3,
'range_km': 1.,
'wlshort': 200.,
'wllong': 30000.,
'wlstep': 20.,
}
TR = lowtran.userhoriztrans(c1)
assert np.isnan(TR['transmission']).all()
def main():
p = ArgumentParser(description='Lowtran 7 interface')
p.add_argument('-z',
'--obsalt',
help='altitude of bother observers on horizontal path [km]',
type=float,
default=0.3)
p.add_argument('-r',
'--range_km',
help='range between observers on horizontal path [km]',
type=float,
default=1.0)
p.add_argument(
'-a',
'--zenang',
help='zenith angle [deg] can be single value or list of values',
type=float,
default=0.)
p.add_argument('-w',
'--wavelen',
help='wavelength range nm (start,stop)',
type=float,
nargs=2,
default=(200, 30000))
P = p.parse_args()
c1 = {
'zmdl': P.obsalt,
'h1': P.obsalt,
'range_km': P.range_km,
'wlnmlim': P.wavelen,
}
atmos = {
'p': 949.,
't': 283.8,
'wmol': [93.96, 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.]
}
c1.update(atmos)
TR = lowtran.userhoriztrans(c1).squeeze()
plothoriz(TR, c1)
show()
def modern_transparency_dict(temp: float, height: float, dist: float, pressure: float = 949.0)\
-> Dict[Tuple[float, float], float]:
"""
Create a table of transparencies for rays of radiation leaving
perpendicular to the Earth's surface. The transparencies correspond
to the different co2 and h2o pairings found in Arrhenius' original tables.
:param temp:
The temperature of the atmosphere
:param height:
The height in the atmosphere at which the transparency values
are calculated
:param dist:
The total length the radiation travels through the atmosphere
:param pressure:
The pressure of the atmosphere in millibars. Optional parameter
defaults to 949.0, the Lowtran default.
:return:
A Dict of transparency values with keys of co2 and h2o pairings/tuples
"""
co2_values = [1.0, 1.2, 1.5, 2.0, 2.5, 3.0, 4.0, 6.0, 10.0, 20.0, 40.0]
h2o_values = [.3, .5, 1.0, 1.5, 2.0, 3.0, 4.0, 6.0, 10.0]
parameters = {
'h1': height,
'zmdl': height,
'range_km': dist,
'wlshort': 200,
'wllong': 20000,
'wlstep': 200,
'p': 949.0,
't': temp,
}
final_table = {}
for co2 in co2_values:
for h2o in h2o_values:
parameters['wmol'] = [
co2, h2o, 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.
]
lowtran_result = userhoriztrans(parameters)
final_table[(co2,
h2o)] = float(lowtran_result['transmission'].mean())
return final_table
def test_userhoriz():
vlim = (200, 30000)
c1 = {'zmdl': 0.3,
'h1': 0.3,
'range_km': 1.,
'wlnmlim': vlim,
}
atmos = {'p': 949., 't': 283.8, 'wmol': [93.96, 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.]}
c1.update(atmos)
TR = lowtran.userhoriztrans(c1)
assert_allclose(TR.wavelength_nm[[0, -1]],
(30303.03, 200), rtol=1e-6)
assert_allclose(TR['transmission'][0, [1000, 1200], 0],
[3.395577e-04, 9.921151e-01], rtol=0.001)
type=float,
default=0.)
p.add_argument('-w',
'--wavelen',
help='wavelength range nm (start,stop)',
type=float,
nargs=2,
default=(200, 30000))
p = p.parse_args()
c1 = {
'zmdl': p.obsalt,
'h1': p.obsalt,
'range_km': p.range_km,
'wlnmlim': p.wavelen,
}
atmos = {
'p': 949.,
't': 283.8,
'wmol': [93.96, 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.]
}
c1.update(atmos)
TR = lowtran.userhoriztrans(c1).squeeze()
plothoriz(TR, c1)
show()