Meteorology#
Warning
This is not meant to be a standalone notebook. This notebook is part of the process we have for adding entries to the NCL Index and is not meant to be used as tutorial or example code.
Functions covered#
NCL code#
; daylight_fao56
; Adapted from https://www.ncl.ucar.edu/Document/Functions/Crop/daylight_fao56.shtml
; ncl -n daylight_fao56.ncl >> daylight_fao56_output.txt
print("DOY, Latitude (Degrees), Daylight Hours")
do doy=0,365
do lat=-66,66
begin
daylight_hours = daylight_fao56(doy, lat)
print (doy +","+ lat +","+ daylight_hours)
end
end do
end do
; dewtemp_trh
; Adapted from https://www.ncl.ucar.edu/Document/Functions/Built-in/dewtemp_trh.shtml
; ncl -n dewtemp_trh.ncl >> dewtemp_trh_output.txt
print("Temperature (K), Relative Humidity (%), Dew Temperature (C)")
do tk=273,374
do rh=1,100
begin
dewtemp = dewtemp_trh(tk,rh)-273.15
print (tk +","+ rh +","+ dewtemp)
end
end do
end do
; satvpr_temp_fao56
; Adapted from https://www.ncl.ucar.edu/Document/Functions/Crop/satvpr_temp_fao56.shtml
; ncl -n satvpr_temp_fao56.ncl >> satvpr_temp_fao56_output.txt
print("Temperature (F), Saturation Vapor Pressure (kPa)")
do temp=33,212
begin
sat_vpr_pressure = satvpr_temp_fao56(temp, (/2, 2/))
print (temp + "," + sat_vpr_pressure)
end
end do
; satvpr_tdew_fao56
; Adapted from https://www.ncl.ucar.edu/Document/Functions/Crop/satvpr_tdew_fao56.shtml
; ncl -n satvpr_tdew_fao56.ncl >> satvpr_tdew_fao56_output.txt
print("Temperature (F), Actual Saturation Vapor Pressure (kPa)")
do temp=33,212
begin
act_sat_vpr_pressure = satvpr_tdew_fao56(temp, (/2, 2/))
print (temp + "," + act_sat_vpr_pressure)
end
end do
; satvpr_slope_fao56
; Adapted from https://www.ncl.ucar.edu/Document/Functions/Crop/satvpr_slope_fao56.shtml
; ncl -n satvpr_slope_fao56.ncl >> satvpr_slope_fao56_output.txt
print("Temperature (F), Slope of Saturation Vapor Pressure Curve (kPa)")
do temp=33,212
begin
slope_satvpr = satvpr_slope_fao56(temp, (/2, 2/))
print (temp + "," + slope_satvpr)
end
end do
; coriolis_param
; Adapted from https://www.ncl.ucar.edu/Document/Functions/Contributed/coriolis_param.shtml
; ncl -n coriolis_param.ncl >> coriolis_param_output.txt
print("Latitude (Degree), Coriolis Parameter")
do lat=-90,90
print(lat + "," + coriolis_param(lat))
end do
; relhum
; Adapted from https://www.ncl.ucar.edu/Document/Functions/Built-in/relhum.shtml
; ncl -n relhum.ncl >> relhum_output.txt
print("Temperature (K), Mixing Ratio (KG/KG), Pressure (Pa)")
do tk=273,290
do mr=1,100
do ppa=10000,15000,500
begin
rh = relhum(tk, mr, ppa)
print (tk + "," + mr + "," + ppa + "," + rh)
end
end do
end do
end do
; relhum_ice
; Adapted from https://www.ncl.ucar.edu/Document/Functions/Built-in/relhum_ice.shtml
; ncl -n relhum_ice.ncl >> relhum_ice_output.txt
print("Temperature (K), Mixing Ratio (KG/KG), Pressure (Pa)")
do tk=173,273
do mr=1,100
do ppa=10000,15000,500
begin
rh = relhum_ice(tk, mr, ppa)
print (tk + "," + mr + "," + ppa + "," + rh)
end
end do
end do
end do
Python Functionality#
dewtemp_trh#
#### Collect NCL values for dewtemp_trh from geocat-datafiles
import geocat.datafiles as gdf
import numpy as np
dewtemp_data = gdf.get('applications_files/ncl_outputs/dewtemp_trh_output.txt')
dewtemp_data = np.loadtxt(dewtemp_data, delimiter=',', skiprows=6)
Downloading file 'applications_files/ncl_outputs/dewtemp_trh_output.txt' from 'https://github.com/NCAR/GeoCAT-datafiles/raw/main/applications_files/ncl_outputs/dewtemp_trh_output.txt' to '/home/runner/.cache/geocat'.
### Collect NCL `dewtemp` value and associated (temperature_kelvin, relative humidity) values
ncl_dewtemp = {}
tk_rh = tuple(map(tuple, dewtemp_data[::, 0:2]))
dewtemp_values = dewtemp_data[::, 2]
ncl_dewtemp = dict(zip(tk_rh, dewtemp_values))
### Collect Temperature (Kelvin) and Relative Humidity Pairs
tk_rh = []
for tk in range(273, 374 + 1):
for rh in range(1, 100 + 1):
tk_rh.append((tk, rh))
### Calculate GeoCAT-Comp `dewtemp` value and tk/rh
from geocat.comp import dewtemp
geocat_dewtemp = {}
for i, pair in enumerate(tk_rh):
tk, rh = pair
geocat_dewtemp[pair] = dewtemp(tk, rh) - 273.15
daylight_fao56#
#### Collect NCL values for daylight_fao56 from geocat-datafiles
import geocat.datafiles as gdf
import numpy as np
daylight_data = gdf.get('applications_files/ncl_outputs/daylight_fao56_output.txt')
daylight_data = np.loadtxt(daylight_data, delimiter=',', skiprows=6)
Downloading file 'applications_files/ncl_outputs/daylight_fao56_output.txt' from 'https://github.com/NCAR/GeoCAT-datafiles/raw/main/applications_files/ncl_outputs/daylight_fao56_output.txt' to '/home/runner/.cache/geocat'.
### Collect NCL `daylight_fao56` value and associated (doy, latitude) values
ncl_daylight = {}
doy_lat = tuple(map(tuple, daylight_data[::, 0:2]))
daylight_values = daylight_data[::, 2]
ncl_daylight = dict(zip(doy_lat, daylight_values))
### Collect DOY and Latitude Pairs
doy_lat = []
for doy in range(0, 365 + 1):
for lat in range(-66, 66 + 1):
doy_lat.append((doy, lat))
### Calculate GeoCAT-Comp `daylight_fao56` value and doy/lat
from geocat.comp import max_daylight
geocat_daylight = {}
for i, pair in enumerate(doy_lat):
doy, lat = pair
geocat_daylight[pair] = max_daylight(doy, lat)
/home/runner/micromamba/envs/geocat-applications/lib/python3.13/site-packages/geocat/comp/meteorology.py:1490: UserWarning: WARNING: max_daylight has limited validity for abs(lat) > 55
warnings.warn("WARNING: max_daylight has limited validity for abs(lat) > 55 ")
satvpr_temp_fao56#
#### Collect NCL values for satvpr_temp_fao56 from geocat-datafiles
import geocat.datafiles as gdf
import numpy as np
satvpr_temp_fao56_data = gdf.get(
'applications_files/ncl_outputs/satvpr_temp_fao56_output.txt'
)
satvpr_temp_fao56_data = np.loadtxt(satvpr_temp_fao56_data, delimiter=',', skiprows=6)
Downloading file 'applications_files/ncl_outputs/satvpr_temp_fao56_output.txt' from 'https://github.com/NCAR/GeoCAT-datafiles/raw/main/applications_files/ncl_outputs/satvpr_temp_fao56_output.txt' to '/home/runner/.cache/geocat'.
### Collect NCL `satvpr_temp_fao56` value and associated (temp, satvpr_temp) values
ncl_satvpr_temp_fao56 = dict(
zip(satvpr_temp_fao56_data[::, 0], satvpr_temp_fao56_data[::, 1])
)
### Calculate GeoCAT-Comp `saturation_vapor_pressure`
from geocat.comp import saturation_vapor_pressure
geocat_satvpr_temp_fao56 = {}
for temp in range(33, 212 + 1):
geocat_satvpr_temp_fao56[temp] = saturation_vapor_pressure(temp)
satvpr_tdew_fao56#
#### Collect NCL values for satvpr_tdew_fao56 from geocat-datafiles
import geocat.datafiles as gdf
import numpy as np
satvpr_tdew_fao56_data = gdf.get(
'applications_files/ncl_outputs/satvpr_tdew_fao56_output.txt'
)
satvpr_tdew_fao56_data = np.loadtxt(satvpr_tdew_fao56_data, delimiter=',', skiprows=6)
Downloading file 'applications_files/ncl_outputs/satvpr_tdew_fao56_output.txt' from 'https://github.com/NCAR/GeoCAT-datafiles/raw/main/applications_files/ncl_outputs/satvpr_tdew_fao56_output.txt' to '/home/runner/.cache/geocat'.
### Collect NCL `satvpr_tdew_fao56` value and associated (temp, act_sat_vapr_pressure) values
ncl_satvpr_tdew_fao56 = dict(
zip(satvpr_tdew_fao56_data[::, 0], satvpr_tdew_fao56_data[::, 1])
)
### Calculate GeoCAT-Comp `actual_saturation_vapor_pressure`
from geocat.comp import actual_saturation_vapor_pressure
geocat_satvpr_tdew_fao56 = {}
for temp in range(33, 212 + 1):
geocat_satvpr_tdew_fao56[temp] = actual_saturation_vapor_pressure(temp)
satvpr_slope_fao56#
#### Collect NCL values for satvpr_slope_fao56 from geocat-datafiles
import geocat.datafiles as gdf
import numpy as np
satvpr_slope_fao56_data = gdf.get(
'applications_files/ncl_outputs/satvpr_slope_fao56_output.txt'
)
satvpr_slope_fao56_data = np.loadtxt(satvpr_slope_fao56_data, delimiter=',', skiprows=6)
Downloading file 'applications_files/ncl_outputs/satvpr_slope_fao56_output.txt' from 'https://github.com/NCAR/GeoCAT-datafiles/raw/main/applications_files/ncl_outputs/satvpr_slope_fao56_output.txt' to '/home/runner/.cache/geocat'.
### Collect NCL `satvpr_slope_fao56` value and associated (temp, slope_satvpr) values
ncl_satvpr_slope_fao56 = dict(
zip(satvpr_slope_fao56_data[::, 0], satvpr_slope_fao56_data[::, 1])
)
### Calculate GeoCAT-Comp `saturation_vapor_pressure_slope`
from geocat.comp import saturation_vapor_pressure_slope
geocat_satvpr_slope_fao56 = {}
for temp in range(33, 212 + 1):
geocat_satvpr_slope_fao56[temp] = saturation_vapor_pressure_slope(temp)
coriolis_param#
#### Collect NCL values for coriolis_param from geocat-datafiles
import geocat.datafiles as gdf
import numpy as np
coriolis_param_data = gdf.get(
'applications_files/ncl_outputs/coriolis_param_output.txt'
)
coriolis_param_data = np.loadtxt(coriolis_param_data, delimiter=',', skiprows=6)
Downloading file 'applications_files/ncl_outputs/coriolis_param_output.txt' from 'https://github.com/NCAR/GeoCAT-datafiles/raw/main/applications_files/ncl_outputs/coriolis_param_output.txt' to '/home/runner/.cache/geocat'.
### Collect NCL `coriolis_param_data` value and associated coriolis parameter values
ncl_coriolis_param = dict(zip(coriolis_param_data[::, 0], coriolis_param_data[::, 1]))
### Calculate MetPy "coriolis_parameter"
from metpy.calc import coriolis_parameter
from metpy.units import units
metpy_coriolis_para = {}
for lat in range(-90, 90 + 1):
metpy_coriolis_para[lat] = coriolis_parameter(lat * units.degree).magnitude
relhum#
#### Collect NCL values for relhum from geocat-datafiles
import geocat.datafiles as gdf
import numpy as np
relhum_data = gdf.get('applications_files/ncl_outputs/relhum_output.txt')
relhum_data = np.loadtxt(relhum_data, delimiter=',', skiprows=6)
Downloading file 'applications_files/ncl_outputs/relhum_output.txt' from 'https://github.com/NCAR/GeoCAT-datafiles/raw/main/applications_files/ncl_outputs/relhum_output.txt' to '/home/runner/.cache/geocat'.
### Collect NCL `relhum` value and associated (temp, mixing ratio) values
ncl_relhum = {}
temp_mr_press = tuple(map(tuple, relhum_data[::, 0:3]))
relhum_values = relhum_data[::, 3]
ncl_relhum = dict(zip(temp_mr_press, relhum_values))
### Collect Temperature, Mixing Ratio, Pressure
temp_mr_press = []
for temp in range(273, 374 + 1):
for mr in range(1, 100 + 1):
for press in range(10000, 15000 + 1, 500):
temp_mr_press.append((temp, mr, press))
### Calculate GeoCAT-Comp `relhum` value and temp/mixing ratio/pressure
from geocat.comp import relhum
geocat_relhum = {}
for i, variables in enumerate(temp_mr_press):
temp, mr, press = variables
geocat_relhum[variables] = relhum(temp, mr, press)
relhum_ice#
#### Collect NCL values for relhum from geocat-datafiles
import geocat.datafiles as gdf
import numpy as np
relhum_ice_data = gdf.get('applications_files/ncl_outputs/relhum_ice_output.txt')
relhum_ice_data = np.loadtxt(relhum_ice_data, delimiter=',', skiprows=6)
Downloading file 'applications_files/ncl_outputs/relhum_ice_output.txt' from 'https://github.com/NCAR/GeoCAT-datafiles/raw/main/applications_files/ncl_outputs/relhum_ice_output.txt' to '/home/runner/.cache/geocat'.
### Collect NCL `relhum_ice` value and associated (temp, mixing ratio) values
ncl_relhum_ice = {}
temp_mr_press = tuple(map(tuple, relhum_ice_data[::, 0:3]))
relhum_ice_values = relhum_ice_data[::, 3]
ncl_relhum_ice = dict(zip(temp_mr_press, relhum_ice_values))
### Collect Temperature, Mixing Ratio, Pressure
temp_mr_press = []
for temp in range(173, 273 + 1):
for mr in range(1, 100 + 1):
for press in range(10000, 15000 + 1, 500):
temp_mr_press.append((temp, mr, press))
### Calculate GeoCAT-Comp `relhum_ice` value and temp/mixing ratio/pressure
from geocat.comp import relhum_ice
geocat_relhum_ice = {}
for i, variables in enumerate(temp_mr_press):
temp, mr, press = variables
geocat_relhum_ice[variables] = relhum_ice(temp, mr, press)
Comparison#
dewtemp_trh#
import math
for pair in ncl_dewtemp.keys():
try:
assert math.isclose(
ncl_dewtemp[pair], geocat_dewtemp[pair], rel_tol=1e-04
) # within 4 decimal points
except Exception:
assert math.isclose(
ncl_dewtemp[pair], geocat_dewtemp[pair], rel_tol=1e-02
) # within 2 decimal points
print(f"{pair}:")
print(f"\t{ncl_dewtemp[pair]}, {geocat_dewtemp[pair]}")
print(f"\tDifference: {ncl_dewtemp[pair] - geocat_dewtemp[pair]}")
(np.float64(274.0), np.float64(94.0)):
-0.0055542, -0.005570036309563875
Difference: 1.5836309563875377e-05
(np.float64(275.0), np.float64(87.0)):
-0.0839233, -0.08393959272956408
Difference: 1.6292729564076902e-05
(np.float64(275.0), np.float64(88.0)):
0.073761, 0.07374617196580857
Difference: 1.482803419142198e-05
(np.float64(277.0), np.float64(76.0)):
0.00259399, 0.0025903565796738803
Difference: 3.633420326119678e-06
(np.float64(278.0), np.float64(71.0)):
0.0261536, 0.026158530424595483
Difference: -4.930424595483984e-06
(np.float64(279.0), np.float64(66.0)):
-0.0278931, -0.027897415813697535
Difference: 4.3158136975342265e-06
(np.float64(281.0), np.float64(58.0)):
0.0712891, 0.07128017477202775
Difference: 8.925227972245153e-06
(np.float64(282.0), np.float64(54.0)):
0.0129395, 0.01291856405322278
Difference: 2.0935946777218828e-05
(np.float64(283.0), np.float64(50.0)):
-0.130432, -0.13044636060385528
Difference: 1.4360603855290144e-05
(np.float64(283.0), np.float64(51.0)):
0.144928, 0.14490829422311435
Difference: 1.9705776885647897e-05
(np.float64(284.0), np.float64(47.0)):
-0.0726318, -0.07262340593854333
Difference: -8.39406145666799e-06
(np.float64(285.0), np.float64(44.0)):
-0.0798035, -0.07982300528288988
Difference: 1.950528288988118e-05
(np.float64(286.0), np.float64(41.0)):
-0.160156, -0.1601734585760255
Difference: 1.7458576025503048e-05
(np.float64(287.0), np.float64(39.0)):
0.0386658, 0.0386467450997543
Difference: 1.905490024570189e-05
(np.float64(290.0), np.float64(32.0)):
-0.0795288, -0.07954541765832346
Difference: 1.6617658323461737e-05
(np.float64(291.0), np.float64(30.0)):
-0.115204, -0.11521555297190389
Difference: 1.1552971903888709e-05
(np.float64(294.0), np.float64(25.0)):
-0.110413, -0.11042499197856159
Difference: 1.1991978561595729e-05
(np.float64(295.0), np.float64(24.0)):
0.156677, 0.15665929836796977
Difference: 1.7701632030242553e-05
(np.float64(297.0), np.float64(21.0)):
-0.0614929, -0.06151243710161225
Difference: 1.953710161224642e-05
(np.float64(299.0), np.float64(19.0)):
0.162537, 0.16251872398265732
Difference: 1.8276017342666595e-05
(np.float64(302.0), np.float64(16.0)):
0.138275, 0.1382598702660971
Difference: 1.5129733902913278e-05
(np.float64(303.0), np.float64(15.0)):
0.0130615, 0.013067891707237322
Difference: -6.391707237322214e-06
daylight_fao56#
import math
for pair in ncl_daylight.keys():
assert math.isclose(
ncl_daylight[pair], geocat_daylight[pair].flatten()[0], rel_tol=1e-05
) # within 5 decimal points
satvpr_temp_fao56#
import math
for key in ncl_satvpr_temp_fao56.keys():
assert math.isclose(
ncl_satvpr_temp_fao56[key], geocat_satvpr_temp_fao56[key], rel_tol=1e-05
) # within 5 decimal points
satvpr_tdew_fao56#
import math
for key in ncl_satvpr_tdew_fao56.keys():
assert math.isclose(
ncl_satvpr_tdew_fao56[key], geocat_satvpr_tdew_fao56[key], rel_tol=1e-05
) # within 5 decimal points
satvpr_slope_fao56#
import math
for key in ncl_satvpr_slope_fao56.keys():
assert math.isclose(
ncl_satvpr_slope_fao56[key], geocat_satvpr_slope_fao56[key], rel_tol=1e-05
) # within 5 decimal points
coriolis_param#
import math
for key in ncl_coriolis_param.keys():
assert math.isclose(
ncl_coriolis_param[key], metpy_coriolis_para[key], rel_tol=1e-04
) # within 4 decimal points
relhum#
import math
for key in ncl_relhum.keys():
assert math.isclose(
ncl_relhum[key], geocat_relhum[key], rel_tol=1e-05
) # within 5 decimal points
relhum_ice#
import math
for key in ncl_relhum_ice.keys():
assert math.isclose(
ncl_relhum_ice[key], geocat_relhum_ice[key], rel_tol=1e-05
) # within 5 decimal points