def calc_sounding_stats(_z, _th, _p, _qv):
T = met.T(_th, _p) # T (K)
pcl = met.CAPE(_z, _p, T, _qv, 1) # CAPE
mupcl = met.CAPE(_z, _p, T, _qv, 2) # MUCAPE
mlpcl = met.CAPE(_z, _p, T, _qv, 3) # MLCAPE
return (pcl, mupcl, mlpcl)
def plot_sounding_data(filename, output):
"""Plot SkewT from a WRF / CM1 compatible sounding data file
:param filename: The name of the file to open.
:type filename: str
:param output: The name of the file to output plot
:type output: str
The datafile is the same format as used in sounding initalization
files for WRF and CM1.
The format is:
1 line header with surface pressure (mb), theta (K) and qv (g/kg)
n number of lines with z (m), theta (K), qv (g/kg), u (m/s), v(m/s)
"""
# load first line of file
with open(filename, 'r') as f:
surface = f.readline()
p0, th0, qv0 = surface.split()
# load rest of file
_z, _th, _qv, _u, _v = np.loadtxt(filename, unpack=True, skiprows=1)
# create arrays with one more z index for surface values
nk = len(_z) + 1
z = np.empty(nk, np.float32)
th = np.empty(nk, np.float32)
qv = np.empty(nk, np.float32)
u = np.empty(nk, np.float32)
v = np.empty(nk, np.float32)
p = np.empty(nk, np.float32)
# copy the arrays, leaving room at the surface
z[1:nk] = _z
th[1:nk] = _th
qv[1:nk] = _qv / 1000.
u[1:nk] = _u
v[1:nk] = _v
# assign surface values
z[0] = 0.
th[0] = float(th0)
qv[0] = float(qv0) / 1000.
u[0] = 1.75 * u[1] - u[2] + 0.25 * u[3]
v[0] = 1.75 * v[1] - v[2] + 0.25 * v[3]
p[0] = float(p0) * 100.
# integrate pressure, assume hydrostatic
# dp = -rho*g*dz
for k in np.arange(1, nk):
p[k] = p[k - 1] * np.exp(
(metconst.g * (z[k - 1] - z[k])) / (metconst.Rd * met.T(
(th[k] + th[k - 1]) / 2., p[k - 1])))
#for k in np.arange(nk):
# print(z[k], p[k], th[k], qv[k], u[k], v[k])
plot(None, z, th, p, qv, u, v, output, title="input sounding")
def draw_dry_adiabat(axes):
"""Plot dry adiabats on axes
:parameter axes: The axes to draw on
:type axes: :py:class:`matplotlib.axes`
This function calculates dry adiabats
and plots these lines. Adiabats are calculated
every 10 K
"""
for T in dry_adiabats:
dry_adiabat = met.T(T + met.T00,
plevs_plot) - met.T00 + skew(plevs_plot)
if (T % 10 == 0):
axes.semilogy(dry_adiabat,
plevs_plot,
basey=math.e,
color=lc_major,
linewidth=lw_major)
else:
axes.semilogy(dry_adiabat,
plevs_plot,
basey=math.e,
color=lc_minor,
linewidth=lw_minor)
for T in np.arange(-20, 150, 10):
p = (600. - 3.5 * T) * 100.
x = met.T(T + met.T00, p) - met.T00 + skew(p)
x1 = met.T(T + met.T00,
p + .5 * dp_plot) - met.T00 + skew(p + .5 * dp_plot)
x2 = met.T(T + met.T00,
p - .5 * dp_plot) - met.T00 + skew(p - .5 * dp_plot)
dx = x2 - x1
theta = math.atan2(-dp_plot, -dx) * 180 / math.pi + 37
label(x, p / 100, str(T), 'black', theta, axes)
def plot_sounding(axes, z, th, p, qv, u=None, v=None):
"""Plot sounding data
This plots temperature, dewpoint and wind data on a Skew-T/Log-P plot.
This will also plot derived values such as wetbulb temperature and
label the surface based LCL, LFC and EL.
:parameter z: height values (1D array)
:parameter th: potential temperature at z heights (1D array)
:parameter p: pressure at z heights (1D array)
:parameter qv: water vapor mixing ratio at z heights (1D array)
:parameter u: U component of wind at z heights (1D array)
:parameter v: V component of wind at z heights (1D array)
:paramter axes: The axes instance to draw on
"""
# calculate Temperature and dewpoint
T = met.T(th, p) - met.T00 # T (C)
Td = met.Td(p, qv) - met.T00 # Td (C)
# calculate wetbulb temperature
Twb = np.empty(len(z), np.float32) # Twb (C)
for zlvl in range(len(z)):
Twb[zlvl] = met.Twb(z, p, th, qv, z[zlvl])
# Get surface parcel CAPE and temperature / height profiles
pcl = met.CAPE(z, p, T + met.T00, qv, 1) # CAPE
T_parcel = pcl['t_p'] - met.T00 # parcel T (C)
T_vparcel = pcl['tv_p'] - met.T00 # parcel Tv (C)
T_venv = met.T(pcl['thv_env'], pcl['pp']) - met.T00 # Env Tv (C)
# plot Temperature, dewpoint, wetbulb and lifted surface parcel profiles on skew axes
axes.semilogy(T + skew(p),
p,
basey=math.e,
color=linecolor_T,
linewidth=linewidth_T)
axes.semilogy(Td + skew(p),
p,
basey=math.e,
color=linecolor_Td,
linewidth=linewidth_Td)
axes.semilogy(T_parcel + skew(pcl['pp']),
pcl['pp'],
basey=math.e,
color=linecolor_Parcel_T,
linewidth=linewidth_Parcel_T)
axes.semilogy(Twb + skew(p),
p,
basey=math.e,
color=linecolor_Twb,
linewidth=linewidth_Twb)
# plot virtual temperature of environment and lifted parcel
axes.semilogy(T_venv + skew(pcl['pp']),
pcl['pp'],
basey=math.e,
color=linecolor_Tve,
linewidth=linewidth_Tve,
linestyle=linestyle_Tve)
axes.semilogy(T_vparcel + skew(pcl['pp']),
pcl['pp'],
basey=math.e,
color=linecolor_Tvp,
linewidth=linewidth_Tvp,
linestyle=linestyle_Tvp)
# Add labels for levels based on surface parcel
#debug print(pcl['lfcprs'], pcl['lclprs'], pcl['elprs'], pcl['ptops'])
if (pcl['lfcprs'] > 0):
label_m(Tmax - .5, pcl['lfcprs'], '--LFC', axes)
if (pcl['lclprs'] > 0):
label_m(Tmax - .5, pcl['lclprs'], '--LCL', axes)
if (pcl['elprs'] > 0):
label_m(Tmax - .5, pcl['elprs'], '--EL', axes)
if (pcl['ptops'] > 0):
label_m(Tmax - .5, pcl['ptops'], '--TOPS', axes)
# plot labels for std heights
for plvl in plevs_std:
zlvl = pymeteo.interp.interp_height(z, p, plvl)
label_m(Tmin - .5, plvl, str(int(zlvl)), axes)
# plot wind barbs on left side of plot. move this? right side?
if (u is not None and v is not None):
#draw_wind_line(axes)
for i in np.arange(0, len(z), 2):
if (p[i] > pt_plot):
plt.barbs(Tmin + 4, p[i], u[i], v[i], length=5, linewidth=.5)