def test_mixed_parcel():
"""Test the mixed parcel calculation."""
pressure = np.array([959., 779.2, 751.3, 724.3, 700., 269.]) * units.hPa
temperature = np.array([22.2, 14.6, 12., 9.4, 7., -38.]) * units.degC
dewpoint = np.array([19., -11.2, -10.8, -10.4, -10., -53.2]) * units.degC
parcel_pressure, parcel_temperature, parcel_dewpoint = mixed_parcel(
pressure, temperature, dewpoint, depth=250 * units.hPa)
assert_almost_equal(parcel_pressure, 959. * units.hPa, 6)
assert_almost_equal(parcel_temperature, 28.7363771 * units.degC, 6)
assert_almost_equal(parcel_dewpoint, 7.1534658 * units.degC, 6)
def test_el_ml():
"""Test equilibrium layer calculation for a mixed parcel."""
levels = np.array([959., 779.2, 751.3, 724.3, 700., 400., 269.]) * units.mbar
temperatures = np.array([22.2, 14.6, 12., 9.4, 7., -25., -35.]) * units.celsius
dewpoints = np.array([19., -11.2, -10.8, -10.4, -10., -35., -53.2]) * units.celsius
__, t_mixed, td_mixed = mixed_parcel(levels, temperatures, dewpoints)
mixed_parcel_prof = parcel_profile(levels, t_mixed, td_mixed)
el_pressure, el_temperature = el(levels, temperatures, dewpoints, mixed_parcel_prof)
assert_almost_equal(el_pressure, 355.834 * units.mbar, 3)
assert_almost_equal(el_temperature, -28.371 * units.degC, 3)
def test_lfc_ml():
"""Test Mixed-Layer LFC calculation."""
levels = np.array([959., 779.2, 751.3, 724.3, 700., 269.]) * units.mbar
temperatures = np.array([22.2, 14.6, 12., 9.4, 7., -49.]) * units.celsius
dewpoints = np.array([19., -11.2, -10.8, -10.4, -10., -53.2]) * units.celsius
__, t_mixed, td_mixed = mixed_parcel(levels, temperatures, dewpoints)
mixed_parcel_prof = parcel_profile(levels, t_mixed, td_mixed)
lfc_pressure, lfc_temp = lfc(levels, temperatures, dewpoints, mixed_parcel_prof)
assert_almost_equal(lfc_pressure, 631.794 * units.mbar, 2)
assert_almost_equal(lfc_temp, -1.862 * units.degC, 2)
def calcMLCAPE(levels, temperature, dewpoint, depth=100.0 * units.hPa):
_, T_parc, Td_par = mixed_parcel(
levels,
temperature,
dewpoint,
depth=depth,
interpolate=False,
)
profile = parcel_profile(levels, T_parc, Td_parc)
cape, cin = cape_cin(levels, temperature, dewpoint, profile)
return cape
def test_mixed_parcel():
"""Test the mixed parcel calculation."""
pressure = np.array([959., 779.2, 751.3, 724.3, 700., 269.]) * units.hPa
temperature = np.array([22.2, 14.6, 12., 9.4, 7., -38.]) * units.degC
dewpoint = np.array([19., -11.2, -10.8, -10.4, -10., -53.2]) * units.degC
parcel_pressure, parcel_temperature, parcel_dewpoint = mixed_parcel(pressure, temperature,
dewpoint,
depth=250 * units.hPa)
assert_almost_equal(parcel_pressure, 959. * units.hPa, 6)
assert_almost_equal(parcel_temperature, 28.7363771 * units.degC, 6)
assert_almost_equal(parcel_dewpoint, 7.1534658 * units.degC, 6)
def getData(self, time, model_vars, mdl2stnd, previous_data=None):
'''
Name:
awips_model_base
Purpose:
A function to get data from NAM40 model to create HDWX products
Inputs:
request : A DataAccessLayer request object
time : List of datatime(s) for data to grab
model_vars : Dictionary with variables/levels to get
mdl2stnd : Dictionary to convert from model variable names
to standardized names
Outputs:
Returns a dictionary containing all data
Keywords:
previous_data : Dictionary with data from previous time step
'''
log = logging.getLogger(__name__)
# Set up function for logger
initTime, fcstTime = get_init_fcst_times(time[0])
data = {
'model': self._request.getLocationNames()[0],
'initTime': initTime,
'fcstTime': fcstTime
}
# Initialize empty dictionary
log.info('Attempting to download {} data'.format(data['model']))
for var in model_vars: # Iterate over variables in the vars list
log.debug('Getting: {}'.format(var))
self._request.setParameters(*model_vars[var]['parameters'])
# Set parameters for the download request
self._request.setLevels(*model_vars[var]['levels'])
# Set levels for the download request
response = DAL.getGridData(self._request, time) # Request the data
for res in response: # Iterate over all data request responses
varName = res.getParameter()
# Get name of the variable in the response
varLvl = res.getLevel()
# Get level of the variable in the response
varName = mdl2stnd[varName]
# Convert variable name to local standarized name
if varName not in data:
data[varName] = {}
# If variable name NOT in data dictionary, initialize new dictionary under key
data[varName][varLvl] = res.getRawData()
# Add data under level name
try: # Try to
unit = units(res.getUnit())
# Get units and convert to MetPy units
except: # On exception
unit = '?'
# Set units to ?
else: # If get units success
data[varName][varLvl] *= unit
# Get data and create MetPy quantity by multiplying by units
log.debug(
'Got data for:\n Var: {}\n Lvl: {}\n Unit: {}'.format(
varName, varLvl, unit))
data['lon'], data['lat'] = res.getLatLonCoords()
# Get latitude and longitude values
data['lon'] *= units('degree')
# Add units of degree to longitude
data['lat'] *= units('degree')
# Add units of degree to latitude
# Absolute vorticity
dx, dy = lat_lon_grid_deltas(data['lon'], data['lat'])
# Get grid spacing in x and y
uTag = mdl2stnd[model_vars['wind']['parameters'][0]]
# Get initial tag name for u-wind
vTag = mdl2stnd[model_vars['wind']['parameters'][1]]
# Get initial tag name for v-wind
if (uTag in data) and (
vTag in data): # If both tags are in the data structure
data['abs_vort'] = {}
# Add absolute vorticity key
for lvl in model_vars['wind'][
'levels']: # Iterate over all leves in the wind data
if (lvl in data[uTag]) and (
lvl in data[vTag]
): # If given level in both u- and v-wind dictionaries
log.debug('Computing absolute vorticity at {}'.format(lvl))
data['abs_vort'][ lvl ] = \
absolute_vorticity( data[uTag][lvl], data[vTag][lvl],
dx, dy, data['lat'] )
# Compute absolute vorticity
# 1000 MB equivalent potential temperature
if ('temperature' in data) and (
'dewpoint'
in data): # If temperature AND depoint data were downloaded
data['theta_e'] = {}
T, Td = 'temperature', 'dewpoint'
if ('1000.0MB' in data[T]) and (
'1000.0MB' in data[Td]
): # If temperature AND depoint data were downloaded
log.debug(
'Computing equivalent potential temperature at 1000 hPa')
data['theta_e']['1000.0MB'] = equivalent_potential_temperature(
1000.0 * units('hPa'), data[T]['1000.0MB'],
data[Td]['1000.0MB'])
return data
# MLCAPE
log.debug('Computing mixed layer CAPE')
T_lvl = list(data[T].keys())
Td_lvl = list(data[Td].keys())
levels = list(set(T_lvl).intersection(Td_lvl))
levels = [float(lvl.replace('MB', '')) for lvl in levels]
levels = sorted(levels, reverse=True)
nLvl = len(levels)
if nLvl > 0:
log.debug(
'Found {} matching levels in temperature and dewpoint data'
.format(nLvl))
nLat, nLon = data['lon'].shape
data['MLCAPE'] = np.zeros((
nLat,
nLon,
), dtype=np.float32) * units('J/kg')
TT = np.zeros((
nLvl,
nLat,
nLon,
), dtype=np.float32) * units('degC')
TTd = np.zeros((
nLvl,
nLat,
nLon,
), dtype=np.float32) * units('degC')
log.debug('Sorting temperature and dewpoint data by level')
for i in range(nLvl):
key = '{:.1f}MB'.format(levels[i])
TT[i, :, :] = data[T][key].to('degC')
TTd[i, :, :] = data[Td][key].to('degC')
levels = np.array(levels) * units.hPa
depth = 100.0 * units.hPa
log.debug('Iterating over grid boxes to compute MLCAPE')
for j in range(nLat):
for i in range(nLon):
try:
_, T_parc, Td_parc = mixed_parcel(
levels,
TT[:, j, i],
TTd[:, j, i],
depth=depth,
interpolate=False,
)
profile = parcel_profile(levels, T_parc, Td_parc)
cape, cin = cape_cin(levels, TT[:, j, i],
TTd[:, j, i], profile)
except:
log.warning(
'Failed to compute MLCAPE for lon/lat: {}; {}'.
format(data['lon'][j, i], data['lat'][j, i]))
else:
data['MLCAPE'][j, i] = cape
return data
