def parcelUAV(T, Td, p):
'''
Inputs: temperature, dewpoint, and pressure
Returns: lcl pressure, lcl temperature, isbelowlcl flag, profile temp
'''
lclpres, lcltemp = mcalc.lcl(p[0] * units.mbar,
T[0] * units.degC, Td[0] * units.degC)
print 'LCL Pressure: %5.2f %s' % (lclpres.magnitude, lclpres.units)
print 'LCL Temperature: %5.2f %s' % (lcltemp.magnitude, lcltemp.units)
# parcel profile
# determine if there are points sampled above lcl
ilcl = np.squeeze(np.where((p * units.mbar) <= lclpres))
# if not, entire profile dry adiabatic
if ilcl.size == 0:
prof = mcalc.dry_lapse(p * units.mbar, T[0] * units.degC).to('degC')
isbelowlcl = 1
# if there are, need to concat dry & moist profile ascents
else:
ilcl = ilcl[0]
prof_dry = mcalc.dry_lapse(p[:ilcl] * units.mbar,
T[0] * units.degC).to('degC')
prof_moist = mcalc.moist_lapse(p[ilcl:] * units.mbar,
prof_dry[-1]).to('degC')
prof = np.concatenate((prof_dry, prof_moist)) * units.degC
isbelowlcl = 0
return lclpres, lcltemp, isbelowlcl, prof
def test_dry_lapse():
"""Test dry_lapse calculation."""
levels = np.array([1000, 900, 864.89]) * units.mbar
temps = dry_lapse(levels, 303.15 * units.kelvin)
assert_array_almost_equal(
temps,
np.array([303.15, 294.16, 290.83]) * units.kelvin, 2)
def showalter_index(pressure, temperature, dewpt):
"""Calculate Showalter Index from pressure temperature and 850 hPa lcl.
Showalter Index derived from [Galway1956]_:
SI = T500 - Tp500
where:
T500 is the measured temperature at 500 hPa
Tp500 is the temperature of the lifted parcel at 500 hPa
Parameters
----------
pressure : `pint.Quantity`
Atmospheric pressure level(s) of interest, in order from highest
to lowest pressure
temperature : `pint.Quantity`
Parcel temperature for corresponding pressure
dewpt (:class: `pint.Quantity`):
Parcel dew point temperatures for corresponding pressure
Returns
-------
`pint.Quantity`
Showalter index in delta degrees celsius
"""
# find the measured temperature and dew point temperature at 850 hPa.
idx850 = np.where(pressure == 850 * units.hPa)
T850 = temperature[idx850]
Td850 = dewpt[idx850]
# find the parcel profile temperature at 500 hPa.
idx500 = np.where(pressure == 500 * units.hPa)
Tp500 = temperature[idx500]
# Calculate lcl at the 850 hPa level
lcl_calc = mpcalc.lcl(850 * units.hPa, T850[0], Td850[0])
lcl_calc = lcl_calc[0]
# Define start and end heights for dry and moist lapse rate calculations
p_strt = 1000 * units.hPa
p_end = 500 * units.hPa
# Calculate parcel temp when raised dry adiabatically from surface to lcl
dl = mpcalc.dry_lapse(lcl_calc, temperature[0], p_strt)
dl = (dl.magnitude - 273.15) * units.degC # Change units to C
# Calculate parcel temp when raised moist adiabatically from lcl to 500mb
ml = mpcalc.moist_lapse(p_end, dl, lcl_calc)
# Calculate the Showalter index
shox = Tp500 - ml
return shox
def test_static_stability_adiabatic():
"""Test static stability calculation with a dry adiabatic profile."""
pressures = [1000., 900., 800., 700., 600., 500.] * units.hPa
temperature_start = 20 * units.degC
temperatures = dry_lapse(pressures, temperature_start)
sigma = static_stability(pressures, temperatures)
truth = np.zeros_like(pressures) * units('J kg^-1 hPa^-2')
# Should be zero with a dry adiabatic profile
assert_almost_equal(sigma, truth, 6)
def test_static_stability_adiabatic():
"""Test static stability calculation with a dry adiabatic profile."""
pressures = [1000., 900., 800., 700., 600., 500.] * units.hPa
temperature_start = 20 * units.degC
temperatures = dry_lapse(pressures, temperature_start)
sigma = static_stability(pressures, temperatures)
truth = np.zeros_like(pressures) * units('J kg^-1 hPa^-2')
# Should be zero with a dry adiabatic profile
assert_almost_equal(sigma, truth, 6)
def calculate_sounding_data(df,field_height,field_temp):
###################################### CALCULATION MAGIC #################################################
# We will pull the data out of the latest soudning into individual variables and assign units. #
# This will Return a dictionary with all the vallculate values. Keys are: #
# "pressure", "temperature", "dewpoint", "height", "windspeed","wind_dir"
###################################### CALCULATION MAGIC #################################################
cache = settings.AppCache
#Retrieves Sounding Details and returns them
key='calculation'+str(field_height)+'_'+str(field_temp)
#If soundings are cached and valid, returns the cache, otherwise retreive new sounding
calc = cache.get(key)
if calc is not None:
logging.info("Calculation Cache Hit")
print("Calculation Cahce Hit")
return calc
logging.info("Calculation Cache Miss")
print("Calculation Cahce Miss")
p = df['pressure'].values * units.hPa
T = df['temperature'].values * units.degC
Td = df['dewpoint'].values * units.degC
alt = df['height'].values * units.ft
wind_speed = df['speed'].values * units.knots
wind_dir = df['direction'].values * units.degrees
wet_bulb = mpcalc.wet_bulb_temperature(p,T,Td)
field_pressure = mpcalc.height_to_pressure_std(field_height*units.ft)
adiabat_line = mpcalc.dry_lapse(p,field_temp*units.degC,ref_pressure=mpcalc.height_to_pressure_std(field_height*units.ft))
#Interpolate Missing Values using linear interpolation
Td_linear = interp1d(alt.magnitude,Td.magnitude)
T_linear = interp1d(alt.magnitude,T.magnitude)
#Calculate the LCL Based on Max Temperature
lcl_pressure, lcl_temperature = mpcalc.lcl(field_pressure,field_temp*units.degC ,Td_linear(field_height)*units.degC)
#parcel_prof = mpcalc.parcel_profile(p, T[0], Td[0]).to('degC')
calc = MeteoCast.UpperAtmData(df, p, T, Td,alt,wind_speed,wind_dir,wet_bulb,field_pressure,lcl_pressure,lcl_temperature,adiabat_line)
cache.set(key, calc, expire=600,tag='Calculation Data ')
return calc
skew.plot_barbs(p, u, v)
skew.ax.set_ylim(1000, 100) # Y limits from 1000 in the botton to 100 millibars to the top
skew.ax.set_xlim(-40, 60) # X limits
# Add the relevant special lines\n",
skew.plot_dry_adiabats()
skew.plot_moist_adiabats()
skew.plot_mixing_lines()
plt.show()
# Calculate LCL height and plot as black dot\n",
from metpy.calc import lcl, dry_lapse
from metpy.units import units, concatenate
l = lcl(p[0], T[0], Td[0]) # we can calculate the lcl level from the starting p, T, Td
lcl_temp = dry_lapse(concatenate((p[0], l)), T[0])[-1].to('degC') # Temperature of the lcl using the dry lapse
skew.plot(l, lcl_temp, 'ko', markerfacecolor='black') # plot the lcl level on the temperature with a black circle (ko) filled
# Calculate full parcel profile and add to plot as black line\n",
from metpy.calc import parcel_profile
prof = parcel_profile(p, T[0], Td[0]).to('degC')
skew.plot(p, prof, 'k', linewidth=2)
# Example of coloring area between profiles
skew.ax.fill_betweenx(p, T, prof, where=T>= prof, facecolor='blue', alpha=0.4)
skew.ax.fill_betweenx(p, T, prof, where=T< prof, facecolor='red', alpha=0.4)
# # An example of a slanted line at constant T -- in this case the 0 isotherm
level = skew.ax.axvline(0, color='c', linestyle='--', linewidth=2) # highligh the 0 degree isoterm
from metpy.plots import Hodograpgh
def atmCalc(height, temp, humid):
print("ATMCALC", height, temp, humid, file=sys.stderr)
mtny = windh(MTNX, height, ratio=1,
yoffset=0)
windx = XVALUES
windy = windh(windx, height)
temp_ = temp * units.degC
initp = mc.height_to_pressure_std(windy[0] * units.meters)
dewpt = mc.dewpoint_from_relative_humidity(temp_, humid / 100.)
lcl_ = mc.lcl(initp, temp_, dewpt, max_iters=50, eps=1e-5)
LCL = mc.pressure_to_height_std(lcl_[0])
if (lcl_[0] > mc.height_to_pressure_std(max(windy) * units.meters)
and LCL > windy[0] * units.meters * 1.000009):
# add LCL to x
xlcl = windh(LCL.to('meters').magnitude, height, inv=True)
windx = np.sort(np.append(windx, xlcl))
windy = windh(windx, height)
pressures = mc.height_to_pressure_std(windy * units.meters)
wvmr0 = mc.mixing_ratio_from_relative_humidity(initp, temp_, humid / 100.)
# now calculate the air parcel temperatures and RH at each position
if (lcl_[0] <= min(pressures)):
T = mc.dry_lapse(pressures, temp_)
RH = [
mc.relative_humidity_from_mixing_ratio(
wvmr0, t, p) for t, p in zip(
T, pressures)]
else:
mini = np.argmin(pressures)
p1 = pressures[:mini + 1]
p2 = pressures[mini:] # with an overlap
p11 = p1[p1 >= lcl_[0] * .9999999] # lower (with tol) with lcl
p12 = p1[p1 < lcl_[0] * 1.000009] # upper (with tol) with lcl
T11 = mc.dry_lapse(p11, temp_)
T12 = mc.moist_lapse(p12, lcl_[1])
T1 = concatenate((T11[:-1], T12))
T2 = mc.dry_lapse(p2, T1[-1])
T = concatenate((T1, T2[1:]))
wvmrtop = mc.saturation_mixing_ratio(pressures[mini], T[mini])
RH=[]
for i in range(len(pressures)):
if pressures[i] > lcl_[0] and i <= mini:
v=mc.relative_humidity_from_mixing_ratio(pressures[i], T[i], wvmr0)
else:
if i < mini:
v=1
else:
v=mc.relative_humidity_from_mixing_ratio(pressures[i], T[i], wvmrtop)
RH.append(v)
#RH = [mc.relative_humidity_from_mixing_ratio(*tp, wvmr0) if tp[1] > lcl_[
#0] and i <= mini else 1.0 if i < mini else
#mc.relative_humidity_from_mixing_ratio(*tp, wvmrtop)
#for i, tp in enumerate(zip(pressures, T))]
RH = concatenate(RH)
return windx, mtny, windy, lcl_, LCL, T.to("degC"), RH
def test_dry_lapse():
"""Test dry_lapse calculation."""
levels = np.array([1000, 900, 864.89]) * units.mbar
temps = dry_lapse(levels, 303.15 * units.kelvin)
assert_array_almost_equal(temps,
np.array([303.15, 294.16, 290.83]) * units.kelvin, 2)
def test_dry_lapse_2_levels():
"""Test dry_lapse calculation when given only two levels."""
temps = dry_lapse(np.array([1000., 500.]) * units.mbar, 293. * units.kelvin)
assert_array_almost_equal(temps, [293., 240.3723] * units.kelvin, 4)
def test_dry_lapse_2_levels():
"""Test dry_lapse calculation when given only two levels."""
temps = dry_lapse(np.array([1000., 500.]) * units.mbar, 293. * units.kelvin)
assert_array_almost_equal(temps, [293., 240.3723] * units.kelvin, 4)
# Create a new figure. The dimensions here give a good aspect ratio
fig = plt.figure(figsize=(9, 9))
skew = SkewT(fig, rotation=45)
# Plot the data using normal plotting functions, in this case using
# log scaling in Y, as dictated by the typical meteorological plot
skew.plot(p, T, 'r')
skew.plot(p, Td, 'g')
skew.plot_barbs(p, u, v)
skew.ax.set_ylim(1000, 100)
skew.ax.set_xlim(-40, 60)
# Calculate LCL height and plot as black dot
l = lcl(p[0], C2K(T[0]), C2K(Td[0]))
skew.plot(l, K2C(dry_lapse(l, C2K(T[0]), p[0])), 'ko',
markerfacecolor='black')
# Calculate full parcel profile and add to plot as black line
prof = K2C(parcel_profile(p, C2K(T[0]), C2K(Td[0])))
skew.plot(p, prof, 'k', linewidth=2)
# Example of coloring area between profiles
skew.ax.fill_betweenx(p, T, prof, where=T>=prof, facecolor='blue', alpha=0.4)
skew.ax.fill_betweenx(p, T, prof, where=T<prof, facecolor='red', alpha=0.4)
# An example of a slanted line at constant T -- in this case the 0
# isotherm
l = skew.ax.axvline(0, color='c', linestyle='--', linewidth=2)
# Add the relevant special lines
###########################################
# Create a new figure. The dimensions here give a good aspect ratio
fig = plt.figure(figsize=(9, 9))
skew = SkewT(fig, rotation=45)
# Plot the data using normal plotting functions, in this case using
# log scaling in Y, as dictated by the typical meteorological plot
skew.plot(p, T, 'r')
skew.plot(p, Td, 'g')
skew.plot_barbs(p, u, v)
skew.ax.set_ylim(1000, 100)
skew.ax.set_xlim(-40, 60)
# Calculate LCL height and plot as black dot
l = mpcalc.lcl(p[0], T[0], Td[0])
lcl_temp = mpcalc.dry_lapse(concatenate((p[0], l)), T[0])[-1].to('degC')
skew.plot(l, lcl_temp, 'ko', markerfacecolor='black')
# Calculate full parcel profile and add to plot as black line
prof = mpcalc.parcel_profile(p, T[0], Td[0]).to('degC')
skew.plot(p, prof, 'k', linewidth=2)
# Example of coloring area between profiles
greater = T >= prof
skew.ax.fill_betweenx(p, T, prof, where=greater, facecolor='blue', alpha=0.4)
skew.ax.fill_betweenx(p, T, prof, where=~greater, facecolor='red', alpha=0.4)
# An example of a slanted line at constant T -- in this case the 0
# isotherm
l = skew.ax.axvline(0, color='c', linestyle='--', linewidth=2)
def plot(self, t, td, p, u, v, lat, long, time):
r"""Displays the Skew-T data on a matplotlib figure.
Args:
t (array-like): A list of temperature values.
td (array-like): A list of dewpoint values.
p (array-like): A list of pressure values.
u (array-like): A list of u-wind component values.
v (array-like): A list of v-wind component values.
lat (string): A string containing the requested latitude value.
long (string): A string containing the requested longitude value.
time (string): A string containing the UTC time requested with seconds truncated.
Returns:
None.
Raises:
None.
"""
# Create a new figure. The dimensions here give a good aspect ratio
self.skew = SkewT(self.figure, rotation=40)
# Plot the data using normal plotting functions, in this case using
# log scaling in Y, as dictated by the typical meteorological plot
self.skew.plot(p, t, 'r')
self.skew.plot(p, td, 'g')
self.skew.plot_barbs(p, u, v, barbcolor='#FF0000', flagcolor='#FF0000')
self.skew.ax.set_ylim(1000, 100)
self.skew.ax.set_xlim(-40, 60)
# Axis colors
self.skew.ax.tick_params(axis='x', colors='#A3A3A4')
self.skew.ax.tick_params(axis='y', colors='#A3A3A4')
# Calculate LCL height and plot as black dot
l = lcl(p[0], t[0], td[0])
lcl_temp = dry_lapse(concatenate((p[0], l)), t[0])[-1].to('degC')
self.skew.plot(l, lcl_temp, 'ko', markerfacecolor='black')
# Calculate full parcel profile and add to plot as black line
prof = parcel_profile(p, t[0], td[0]).to('degC')
self.skew.plot(p, prof, 'k', linewidth=2)
# Color shade areas between profiles
self.skew.ax.fill_betweenx(p, t, prof, where=t >= prof, facecolor='#5D8C53', alpha=0.7)
self.skew.ax.fill_betweenx(p, t, prof, where=t < prof, facecolor='#CD6659', alpha=0.7)
# Add the relevant special lines
self.skew.plot_dry_adiabats()
self.skew.plot_moist_adiabats()
self.skew.plot_mixing_lines()
# Set title
deg = u'\N{DEGREE SIGN}'
self.skew.ax.set_title('Sounding for ' + lat + deg + ', ' + long + deg + ' at ' + time + 'z', y=1.02,
color='#A3A3A4')
# Discards old graph, works poorly though
# skew.ax.hold(False)
# Figure and canvas widgets that display the figure in the GUI
# set canvas size to display Skew-T appropriately
self.canvas.setMaximumSize(QtCore.QSize(800, 2000))
# refresh canvas
self.canvas.draw()
#
# Often times we will want to calculate some thermodynamic parameters of a
# sounding. The MetPy calc module has many such calculations already implemented!
#
# * **Lifting Condensation Level (LCL)** - The level at which an air parcel's
# relative humidity becomes 100% when lifted along a dry adiabatic path.
# * **Parcel Path** - Path followed by a hypothetical parcel of air, beginning
# at the surface temperature/pressure and rising dry adiabatically until
# reaching the LCL, then rising moist adiabatially.
# Calculate the LCL level
parcel_lcl = mpcalc.lcl(p[0], T[0], Td[0])
# Determine the LCL temperature by lifting a parcel from the surface
# pressure and temperature via a dry adiabatic process.
lcl_temperature = mpcalc.dry_lapse(concatenate((p[0], parcel_lcl)),
T[0])[-1].to('degC')
print(parcel_lcl, lcl_temperature)
# Calculate the parcel profile.
parcel_prof = mpcalc.parcel_profile(p, T[0], Td[0]).to('degC')
##########################################################################
# Basic Skew-T Plotting
# ---------------------
#
# The Skew-T (log-P) diagram is the standard way to view rawinsonde data. The
# y-axis is height in pressure coordinates and the x-axis is temperature. The
# y coordinates are plotted on a logarithmic scale and the x coordinate system
# is skewed. An explanation of skew-T interpretation is beyond the scope of this
# tutorial, but here we will plot one that can be used for analysis or
(Tmean + 273.15) * units.kelvin))
w = np.multiply(RHmean / 100., ws * 1000.)
# check for RH
if isRH:
lclpres, lcltemp = mcalc.lcl(pres[0] * units.mbar, Tmean[0] * units.degC,
Td[0] * units.degC)
print 'LCL Pressure: {}'.format(lclpres)
print 'LCL Temperature: {}'.format(lcltemp)
# parcel profile
# determine if there are points sampled above lcl
ilcl = np.squeeze(np.where((pres * units.mbar) <= lclpres))
# if not, entire profile dry adiabatic
if ilcl.size == 0:
prof = mcalc.dry_lapse(pres * units.mbar,
Tmean[0] * units.degC).to('degC')
isbelowlcl = 1
# if there are, need to concat dry & moist profile ascents
else:
ilcl = ilcl[0]
prof_dry = mcalc.dry_lapse(pres[:ilcl] * units.mbar,
Tmean[0] * units.degC).to('degC')
prof_moist = mcalc.moist_lapse(pres[ilcl:] * units.mbar,
prof_dry[-1]).to('degC')
prof = np.concatenate((prof_dry, prof_moist)) * units.degC
isbelowlcl = 0
# CAPE
SBCAPE = wxtools.uavCAPE(Tmean * units.degC, prof, pres)
print 'Parcel Buoyancy: {}'.format(SBCAPE)
else:
# Create a new figure. The dimensions here give a good aspect ratio fig = plt.figure(figsize=(9, 9)) skew = SkewT(fig, rotation=45) # Plot the data using normal plotting functions, in this case using # log scaling in Y, as dictated by the typical meteorological plot skew.plot(p, T, 'r') skew.plot(p, Td, 'g') skew.plot_barbs(p, u, v) skew.ax.set_ylim(1000, 100) skew.ax.set_xlim(-40, 60) # Calculate LCL height and plot as black dot l = lcl(p[0], C2K(T[0]), C2K(Td[0])) skew.plot(l, K2C(dry_lapse(l, C2K(T[0]), p[0])), 'ko', markerfacecolor='black') # Calculate full parcel profile and add to plot as black line prof = K2C(parcel_profile(p, C2K(T[0]), C2K(Td[0]))) skew.plot(p, prof, 'k', linewidth=2) # Example of coloring area between profiles skew.ax.fill_betweenx(p, T, prof, where=T >= prof, facecolor='blue', alpha=0.4) skew.ax.fill_betweenx(p, T, prof, where=T < prof, facecolor='red', alpha=0.4) # An example of a slanted line at constant T -- in this case the 0 # isotherm l = skew.ax.axvline(0, color='c', linestyle='--', linewidth=2) # Add the relevant special lines skew.plot_dry_adiabats()
