def lapse_rate(lower, upper, prof, pres=1):
'''
Calculates the lapse rate (C/km) from a profile object
Inputs
------
lower (float) Lower Bound of lapse rate
upper (float) Upper Bound of lapse rate
prof (profile object) Profile Object
pres (int 0/1) Flag to know to convert pres to height
Returns
-------
lapse rate (float [C/km])
'''
if pres:
p1 = lower
p2 = upper
z1 = interp.hght(lower, prof)
z2 = interp.hght(upper, prof)
else:
z1 = interp.msl(lower, prof)
z2 = interp.msl(upper, prof)
p1 = interp.pres(z1, prof)
p2 = interp.pres(z2, prof)
tv1 = interp.vtmp(p1, prof)
tv2 = interp.vtmp(p2, prof)
if not QC(tv1) or not QC(tv2): return RMISSD
return (tv2 - tv1) / (z2 - z1) * -1000.
def lapse_rate(lower, upper, prof, pres=1):
'''
Calculates the lapse rate (C/km) from a profile object
Inputs
------
lower (float) Lower Bound of lapse rate
upper (float) Upper Bound of lapse rate
prof (profile object) Profile Object
pres (int 0/1) Flag to know to convert pres to height
Returns
-------
lapse rate (float [C/km])
'''
if pres:
p1 = lower
p2 = upper
z1 = interp.hght(lower, prof)
z2 = interp.hght(upper, prof)
else:
z1 = interp.msl(lower, prof)
z2 = interp.msl(upper, prof)
p1 = interp.pres(z1, prof)
p2 = interp.pres(z2, prof)
tv1 = interp.vtmp(p1, prof)
tv2 = interp.vtmp(p2, prof)
if not QC(tv1) or not QC(tv2): return RMISSD
return (tv2 - tv1) / (z2 - z1) * -1000.
def non_parcel_bunkers_motion(prof):
'''
Compute the Bunkers Storm Motion for a Right Moving Supercell
Inputs
------
prof (profile object) Profile Object
Returns
-------
rstu (float) Right Storm Motion U-component
rstv (float) Right Storm Motion V-component
lstu (float) Left Storm Motion U-component
lstv (float) Left Storm Motion V-component
'''
d = MS2KTS(7.5) # Deviation value emperically derived as 7.5 m/s
msl6km = interp.msl(6000., prof)
p6km = interp.pres(msl6km, prof)
# SFC-6km Mean Wind
mnu6, mnv6 = mean_wind_npw(prof.gSndg[prof.sfc][prof.pind], p6km, prof, 20)
# SFC-6km Shear Vector
shru6, shrv6 = wind_shear(prof.gSndg[prof.sfc][prof.pind], p6km, prof)
# Bunkers Right Motion
tmp = d / vector.comp2vec(shru6, shrv6)[1]
rstu = mnu6 + (tmp * shrv6)
rstv = mnv6 - (tmp * shru6)
lstu = mnu6 - (tmp * shrv6)
lstv = mnv6 + (tmp * shru6)
return rstu, rstv, lstu, lstv
def corfidi_mcs_motion(prof):
'''
Calculated the Meso-beta Elements (Corfidi) Vectors
Inputs
------
prof (profile object) Profile Object
Returns
-------
upu (float) U-component of the upshear vector
upv (float) V-component of the upshear vector
dnu (float) U-component of the downshear vector
dnv (float) V-component of the downshear vector
'''
# Compute the tropospheric (850hPa-300hPa) mean wind
mnu1, mnv1 = mean_wind_npw(850., 300., prof)
# Compute the low-level (SFC-1500m) mean wind
p_1p5km = interp.pres(interp.msl(1500., prof), prof)
mnu2, mnv2 = mean_wind_npw(prof.gSndg[prof.sfc][prof.pind], p_1p5km, prof)
# Compute the upshear vector
upu = mnu1 - mnu2
upv = mnv1 - mnv2
# Compute the downshear vector
dnu = mnu1 + upu
dnv = mnv1 + upv
return upu, upv, dnu, dnv
def non_parcel_bunkers_motion(prof):
'''
Compute the Bunkers Storm Motion for a Right Moving Supercell
Inputs
------
prof (profile object) Profile Object
Returns
-------
rstu (float) Right Storm Motion U-component
rstv (float) Right Storm Motion V-component
lstu (float) Left Storm Motion U-component
lstv (float) Left Storm Motion V-component
'''
d = MS2KTS(7.5) # Deviation value emperically derived as 7.5 m/s
msl6km = interp.msl(6000., prof)
p6km = interp.pres(msl6km, prof)
# SFC-6km Mean Wind
mnu6, mnv6 = mean_wind_npw(prof.gSndg[prof.sfc][prof.pind],
p6km, prof, 20)
# SFC-6km Shear Vector
shru6, shrv6 = wind_shear(prof.gSndg[prof.sfc][prof.pind],
p6km, prof)
# Bunkers Right Motion
tmp = d / vector.comp2vec(shru6, shrv6)[1]
rstu = mnu6 + (tmp * shrv6)
rstv = mnv6 - (tmp * shru6)
lstu = mnu6 - (tmp * shrv6)
lstv = mnv6 + (tmp * shru6)
return rstu, rstv, lstu, lstv
def corfidi_mcs_motion(prof):
'''
Calculated the Meso-beta Elements (Corfidi) Vectors
Inputs
------
prof (profile object) Profile Object
Returns
-------
upu (float) U-component of the upshear vector
upv (float) V-component of the upshear vector
dnu (float) U-component of the downshear vector
dnv (float) V-component of the downshear vector
'''
# Compute the tropospheric (850hPa-300hPa) mean wind
mnu1, mnv1 = mean_wind_npw(850., 300., prof)
# Compute the low-level (SFC-1500m) mean wind
p_1p5km = interp.pres(interp.msl(1500., prof), prof)
mnu2, mnv2 = mean_wind_npw(prof.gSndg[prof.sfc][prof.pind], p_1p5km, prof)
# Compute the upshear vector
upu = mnu1 - mnu2
upv = mnv1 - mnv2
# Compute the downshear vector
dnu = mnu1 + upu
dnv = mnv1 + upv
return upu, upv, dnu, dnv
def bulk_rich(pcl, prof):
'''
Calculates the Bulk Richardson Number for a given parcel.
Inputs
------
pcl (parcel object) Parcel Object
prof (profile object) Profile Object
Returns
-------
Bulk Richardson Number
'''
# Make sure parcel is initialized
if pcl.lplvals.flag == RMISSD:
pbot = RMISSD
elif pcl.lplvals.flag > 0 and pcl.lplvals.flag < 4:
ptop = interp.pres(interp.msl(6000., prof), prof)
pbot = prof.gSndg[prof.sfc][prof.pind]
else:
h0 = interp.hght(pcl.pres, prof)
try:
pbot = interp.pres(h0 - 500., prof)
except:
pbot = RMISSD
if not QC(pbot): pbot = prof.gSndg[prof.sfc][prof.pind]
h1 = interp.hght(pbot, prof)
ptop = interp.pres(h1 + 6000., prof)
if not QC(pbot) or not QC(ptop):
pcl.brnshear = RMISSD
pcl.brn = RMISSD
return pcl
# Calculate lowest 500m mean wind
p = interp.pres(interp.hght(pbot, prof) + 500., prof)
mnlu, mnlv = winds.mean_wind(pbot, p, prof)
# Calculate the 6000m mean wind
mnuu, mnuv = winds.mean_wind(pbot, ptop, prof)
# Make sure CAPE and Shear are available
if not QC(pcl.bplus) or not QC(mnlu) or not QC(mnuu):
pcl.brnshear = RMISSD
pcl.brn = RMISSD
return pcl
# Calculate shear between levels
dx = mnuu - mnlu
dy = mnuv - mnlv
pcl.brnshear = KTS2MS(vector.comp2vec(dx, dy)[1])
pcl.brnshear = pcl.brnshear**2 / 2.
pcl.brn = pcl.bplus / pcl.brnshear
return pcl
def bunkers_storm_motion(prof, pbot=None, **kwargs):
'''
Compute the Bunkers Storm Motion for a Right Moving Supercell using
a parcel based approach.
Inputs
------
prof (profile object) Profile Object
pbot (float) Base of effective-inflow layer (hPa)
Returns
-------
rstu (float) Right Storm Motion U-component
rstv (float) Right Storm Motion V-component
lstu (float) Left Storm Motion U-component
lstv (float) Left Storm Motion V-component
'''
d = MS2KTS(7.5) # Deviation value emperically derived as 7.5 m/s
# If MUPCL provided, use it, otherwise create MUPCL
if 'mupcl' in kwargs:
mupcl = kwargs.get('mupcl')
else:
mulplvals = params.DefineParcel(3, prof, pres=400)
mupcl = params.parcelx(-1,
-1,
mulplvals.pres,
mulplvals.temp,
mulplvals.dwpt,
prof,
lplvals=mulplvals)
mucape = mupcl.bplus
mucinh = mupcl.bminus
muel = mupcl.elhght
if not pbot:
pbot, ptop = effective_inflow_layer(100, -250, prof)
base = interp.agl(interp.hght(pbot, prof), prof)
if mucape > 100. and QC(muel) and base >= 750:
depth = muel - base
htop = base + depth / 2.
ptop = interp.pres(interp.msl(base + htop, prof), prof)
mnu, mnv = winds.mean_wind_npw(pbot, ptop, prof)
sru, srv = winds.wind_shear(pbot, ptop, prof)
srmag = vector.mag(sru, srv)
uchg = d / srmag * srv
vchg = d / srmag * sru
rstu = mnu + uchg
rstv = mnv - vchg
lstu = mnu - uchg
lstv = mnv + vchg
else:
rstu, rstv, lstu, lstv = winds.non_parcel_bunkers_motion(prof)
return rstu, rstv, lstu, lstv
def bulk_rich(pcl, prof):
'''
Calculates the Bulk Richardson Number for a given parcel.
Inputs
------
pcl (parcel object) Parcel Object
prof (profile object) Profile Object
Returns
-------
Bulk Richardson Number
'''
# Make sure parcel is initialized
if pcl.lplvals.flag == RMISSD:
pbot = RMISSD
elif pcl.lplvals.flag > 0 and pcl.lplvals.flag < 4:
ptop = interp.pres(interp.msl(6000., prof), prof)
pbot = prof.gSndg[prof.sfc][prof.pind]
else:
h0 = interp.hght(pcl.pres, prof)
try:
pbot = interp.pres(h0 - 500., prof)
except:
pbot = RMISSD
if not QC(pbot): pbot = prof.gSndg[prof.sfc][prof.pind]
h1 = interp.hght(pbot, prof)
ptop = interp.pres(h1 + 6000., prof)
if not QC(pbot) or not QC(ptop):
pcl.brnshear = RMISSD
pcl.brn = RMISSD
return pcl
# Calculate lowest 500m mean wind
p = interp.pres(interp.hght(pbot, prof) + 500., prof)
mnlu, mnlv = winds.mean_wind(pbot, p, prof)
# Calculate the 6000m mean wind
mnuu, mnuv = winds.mean_wind(pbot, ptop, prof)
# Make sure CAPE and Shear are available
if not QC(pcl.bplus) or not QC(mnlu) or not QC(mnuu):
pcl.brnshear = RMISSD
pcl.brn = RMISSD
return pcl
# Calculate shear between levels
dx = mnuu - mnlu
dy = mnuv - mnlv
pcl.brnshear = KTS2MS(vector.comp2vec(dx, dy)[1])
pcl.brnshear = pcl.brnshear**2 / 2.
pcl.brn = pcl.bplus / pcl.brnshear
return pcl
def bunkers_storm_motion(prof, pbot=None, **kwargs):
'''
Compute the Bunkers Storm Motion for a Right Moving Supercell using
a parcel based approach.
Inputs
------
prof (profile object) Profile Object
pbot (float) Base of effective-inflow layer (hPa)
Returns
-------
rstu (float) Right Storm Motion U-component
rstv (float) Right Storm Motion V-component
lstu (float) Left Storm Motion U-component
lstv (float) Left Storm Motion V-component
'''
d = MS2KTS(7.5) # Deviation value emperically derived as 7.5 m/s
# If MUPCL provided, use it, otherwise create MUPCL
if 'mupcl' in kwargs:
mupcl = kwargs.get('mupcl')
else:
mulplvals = params.DefineParcel(3, prof, pres=400)
mupcl = params.parcelx(-1, -1, mulplvals.pres, mulplvals.temp,
mulplvals.dwpt, prof, lplvals=mulplvals)
mucape = mupcl.bplus
mucinh = mupcl.bminus
muel = mupcl.elhght
if not pbot:
pbot, ptop = effective_inflow_layer(100, -250, prof)
base = interp.agl(interp.hght(pbot, prof), prof)
if mucape > 100. and QC(muel) and base >= 750:
depth = muel - base
htop = base + depth / 2.
ptop = interp.pres(interp.msl(base + htop, prof), prof)
mnu, mnv = winds.mean_wind_npw(pbot, ptop, prof)
sru, srv = winds.wind_shear(pbot, ptop, prof)
srmag = vector.mag(sru, srv)
uchg = d / srmag * srv
vchg = d / srmag * sru
rstu = mnu + uchg
rstv = mnv - vchg
lstu = mnu - uchg
lstv = mnv + vchg
else:
rstu, rstv, lstu, lstv = winds.non_parcel_bunkers_motion(prof)
return rstu, rstv, lstu, lstv
def parcelx(lower, upper, pres, temp, dwpt, prof, **kwargs):
'''
Lifts the specified parcel, calculated various levels and parameters from
the profile object. B+/B- are calculated based on the specified layer.
!! All calculations use the virtual temperature correction unless noted. !!
Inputs
------
lower (float) Lower-bound lifting level (hPa)
upper (float) Upper-bound lifting level
pres (float) Pressure of parcel to lift (hPa)
temp (float) Temperature of parcel to lift (C)
dwpt (float) Dew Point of parcel to lift (C)
prof (profile object) Profile Object
Returns
-------
pcl (parcel object) Parcel Object
'''
pcl = Parcel(-1, -1, pres, temp, dwpt)
if 'lplvals' in kwargs: pcl.lplvals = kwargs.get('lplvals')
else:
lplvals = DefineParcel(prof, 5, pres=pres, temp=temp, dwpt=dwpt)
pcl.lplvals = lplvals
if prof.gNumLevels < 1: return pcl
lyre = -1
cap_strength = RMISSD
cap_strengthpres = RMISSD
li_max = RMISSD
li_maxpres = RMISSD
totp = 0.
totn = 0.
tote = 0.
cinh_old = 0.
# See if default layer is specified
if lower == -1:
lower = prof.gSndg[prof.sfc][prof.pind]
pcl.blayer = lower
if upper == -1:
upper = prof.gSndg[prof.gNumLevels - 1][prof.pind]
pcl.tlayer = upper
# Make sure that this is a valid layer
if lower > pres:
lower = pres
pcl.blayer = lower
if not QC(interp.vtmp(lower, prof)) or \
not QC(interp.vtmp(upper, prof)):
return RMISSD
# Begin with the Mixing Layer
te1 = interp.vtmp(pres, prof)
pe1 = lower
h1 = interp.hght(pe1, prof)
tp1 = thermo.virtemp(pres, temp, dwpt)
# te1 = tp1
# Lift parcel and return LCL pres (hPa) and LCL temp (c)
pe2, tp2 = thermo.drylift(pres, temp, dwpt)
blupper = pe2 # Define top of layer as LCL pres
h2 = interp.hght(pe2, prof)
te2 = interp.vtmp(pe2, prof)
pcl.lclpres = pe2
pcl.lclhght = interp.agl(h2, prof)
# Calculate lifted parcel theta for use in iterative CINH loop below
# RECALL: lifted parcel theta is CONSTANT from LPL to LCL
theta_parcel = thermo.theta(pe2, tp2, 1000.)
# Environmental theta and mixing ratio at LPL
bltheta = thermo.theta(pres, interp.temp(pres, prof), 1000.)
blmr = thermo.mixratio(pres, dwpt)
# ACCUMULATED CINH IN MIXING LAYER BELOW THE LCL
# This will be done in 10mb increments, and will use the virtual
# temperature correction where possible
pinc = -10
a = int(lower)
b = int(blupper)
for pp in range(a, b, int(pinc)):
pp1 = pp
pp2 = pp + pinc
if pp2 < blupper: pp2 = blupper
dz = interp.hght(pp2, prof) - interp.hght(pp1, prof)
# Calculate difference between Tv_parcel and Tv_environment at top
# and bottom of 10mb layers. Make use of constant lifted parcel
# theta and mixing ratio from LPL to LCL
tv_env_bot = thermo.virtemp(
pp1, thermo.theta(pp1, interp.temp(pp1, prof), 1000.),
interp.dwpt(pp1, prof))
tdef1 = (thermo.virtemp(pp1, theta_parcel,
thermo.temp_at_mixrat(blmr, pp1)) - tv_env_bot) / \
(thermo.ctok(tv_env_bot))
tv_env_top = thermo.virtemp(
pp2, thermo.theta(pp2, interp.temp(pp2, prof), 1000.),
interp.dwpt(pp2, prof))
tdef2 = (thermo.virtemp(pp2, theta_parcel,
thermo.temp_at_mixrat(blmr, pp2)) - tv_env_top) / \
(thermo.ctok(tv_env_bot))
lyre = G * (tdef1 + tdef2) / 2. * dz
if lyre < 0: totn += lyre
# Move the bottom layer to the top of the boundary layer
if lower > pe2:
lower = pe2
pcl.blayer = lower
# Calculate height of various temperature levels
p0c = temp_lvl(0., prof)
pm10c = temp_lvl(-10., prof)
pm20c = temp_lvl(-20., prof)
pm30c = temp_lvl(-30., prof)
hgt0c = interp.hght(p0c, prof)
hgtm10c = interp.hght(pm10c, prof)
hgtm20c = interp.hght(pm20c, prof)
hgtm30c = interp.hght(pm30c, prof)
pcl.p0c = p0c
pcl.pm10c = pm10c
pcl.pm20c = pm20c
pcl.pm30c = pm30c
pcl.hght0c = hgt0c
pcl.hghtm10c = hgtm10c
pcl.hghtm20c = hgtm20c
pcl.hghtm30c = hgtm30c
# Find lowest observation in layer
i = 0
while prof.gSndg[i][prof.pind] > lower:
if i == prof.gNumLevels - 1: break
i += 1
while not QC(prof.gSndg[i][prof.tdind]):
if i == prof.gNumLevels - 1: break
i += 1
lptr = i
if prof.gSndg[i][prof.pind] == lower:
if i != prof.gNumLevels - 1: lptr += 1
# Find highest observation in layer
i = prof.gNumLevels - 1
while prof.gSndg[i][prof.pind] < upper:
if i < lptr: break
i -= 1
uptr = i
if prof.gSndg[i][prof.pind] == upper:
if i > lptr: uptr -= 1
# START WITH INTERPOLATED BOTTOM LAYER
# Begin moist ascent from lifted parcel LCL (pe2, tp2)
pe1 = lower
h1 = interp.hght(pe1, prof)
te1 = interp.vtmp(pe1, prof)
tp1 = thermo.wetlift(pe2, tp2, pe1)
lyre = 0
lyrlast = 0
for i in range(lptr, prof.gNumLevels):
if not QC(prof.gSndg[i][prof.tind]): continue
pe2 = prof.gSndg[i][prof.pind]
h2 = prof.gSndg[i][prof.zind]
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe1, tp1, pe2)
tdef1 = (thermo.virtemp(pe1, tp1, tp1) - te1) / thermo.ctok(te1)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / thermo.ctok(te2)
lyrlast = lyre
lyre = G * (tdef1 + tdef2) / 2. * (h2 - h1)
# Add layer energy to total positive if lyre > 0
if lyre > 0:
totp += lyre
# Add layer energy to total negative if lyre < 0, only up to EL
else:
if pe2 > 500.: totn += lyre
# Check for Max LI
mli = thermo.virtemp(pe2, tp2, tp2) - te2
if mli > li_max:
li_max = mli
li_maxpres = pe2
# Check for Max Cap Strength
mcap = te2 - mli
if mcap > cap_strength:
cap_strength = mcap
cap_strengthpres = pe2
tote += lyre
pelast = pe1
pe1 = pe2
h1 = h2
te1 = te2
tp1 = tp2
# Is this the top of the specified layer
if i >= uptr and not QC(pcl.bplus):
pe3 = pe1
h3 = h1
te3 = te1
tp3 = tp1
lyrf = lyre
if lyrf > 0:
pcl.bplus = totp - lyrf
pcl.bminus = totn
else:
pcl.bplus = totp
if pe2 > 500.: pcl.bminus = totn + lyrf
else: pcl.bminus = totn
pe2 = upper
h2 = interp.hght(pe2, prof)
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (h2 - h3)
if lyrf > 0: pcl.bplus += lyrf
else:
if pe2 > 500.: pcl.bminus += lyrf
if pcl.bplus == 0: pcl.bminus = 0.
# Is this the freezing level
if te2 < 0. and not QC(pcl.bfzl):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0.: pcl.bfzl = totp - lyrf
else: pcl.bfzl = totp
if not QC(p0c) or p0c > pe3:
pcl.bfzl = 0
elif QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (hgt0c - h3)
if lyrf > 0: pcl.bfzl += lyrf
# Is this the -10C level
if te2 < -10. and not QC(pcl.wm10c):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0.: pcl.wm10c = totp - lyrf
else: pcl.wm10c = totp
if not QC(pm10c) or pm10c > pcl.lclpres:
pcl.wm10c = 0
elif QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (hgtm10c - h3)
if lyrf > 0: pcl.wm10c += lyrf
# Is this the -20C level
if te2 < -20. and not QC(pcl.wm20c):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0.: pcl.wm20c = totp - lyrf
else: pcl.wm20c = totp
if not QC(pm20c) or pm20c > pcl.lclpres:
pcl.wm20c = 0
elif QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (hgtm20c - h3)
if lyrf > 0: pcl.wm20c += lyrf
# Is this the -30C level
if te2 < -30. and not QC(pcl.wm30c):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0.: pcl.wm30c = totp - lyrf
else: pcl.wm30c = totp
if not QC(pm30c) or pm30c > pcl.lclpres:
pcl.wm30c = 0
elif QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (hgtm30c - h3)
if lyrf > 0: pcl.wm30c += lyrf
# Is this the 3km level
if pcl.lclhght < 3000.:
h = interp.agl(interp.hght(pe2, prof), prof)
if h >= 3000. and not QC(pcl.b3km):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0: pcl.b3km = totp - lyrf
else: pcl.b3km = totp
h2 = interp.msl(3000., prof)
pe2 = interp.pres(h2, prof)
if QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (h2 - h3)
if lyrf > 0: pcl.b3km += lyrf
else: pcl.b3km = 0.
# Is this the 6km level
if pcl.lclhght < 6000.:
h = interp.agl(interp.hght(pe2, prof), prof)
if h >= 6000. and not QC(pcl.b6km):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0: pcl.b6km = totp - lyrf
else: pcl.b6km = totp
h2 = interp.msl(6000., prof)
pe2 = interp.pres(h2, prof)
if QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (h2 - h3)
if lyrf > 0: pcl.b6km += lyrf
else: pcl.b6km = 0.
# LFC Possibility
if lyre >= 0. and lyrlast <= 0.:
tp3 = tp1
te3 = te1
pe2 = pe1
pe3 = pelast
while interp.vtmp(pe3, prof) > thermo.virtemp(
pe3, thermo.wetlift(pe2, tp3, pe3),
thermo.wetlift(pe2, tp3, pe3)):
pe3 -= 5
pcl.lfcpres = pe3
pcl.lfchght = interp.agl(interp.hght(pe3, prof), prof)
cinh_old = totn
tote = 0.
pcl.elpres = RMISSD
li_max = RMISSD
if cap_strength < 0.: cap_strength = 0.
pcl.cap = cap_strength
pcl.cappres = cap_strengthpres
# Hack to force LFC to be at least at the LCL
if pcl.lfcpres > pcl.lclpres:
pcl.lfcpres = pcl.lclpres
pcl.lfchght = pcl.lclhght
# EL Possibility
if lyre <= 0. and lyrlast >= 0.:
tp3 = tp1
te3 = te1
pe2 = pe1
pe3 = pelast
while interp.vtmp(pe3, prof) < thermo.virtemp(
pe3, thermo.wetlift(pe2, tp3, pe3),
thermo.wetlift(pe2, tp3, pe3)):
pe3 -= 5
pcl.elpres = pe3
pcl.elhght = interp.agl(interp.hght(pe3, prof), prof)
pcl.mplpres = RMISSD
pcl.limax = -li_max
pcl.limaxpress = li_maxpres
# MPL Possibility
if tote < 0. and not QC(pcl.mplpres) and QC(pcl.elpres):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
totx = tote - lyre
pe2 = pelast
while totx > 0:
pe2 -= 1
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
h2 = interp.hght(pe2, prof)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (h2 - h3)
totx += lyrf
tp3 = tp2
te3 = te2
pe3 = pe2
pcl.mplpres = pe2
pcl.mplhght = interp.agl(interp.hght(pe2, prof), prof)
# 500 hPa Lifted Index
if prof.gSndg[i][prof.pind] <= 500. and pcl.li5 == RMISSD:
a = interp.vtmp(500., prof)
b = thermo.wetlift(pe1, tp1, 500.)
pcl.li5 = a - thermo.virtemp(500, b, b)
# 300 hPa Lifted Index
if prof.gSndg[i][prof.pind] <= 300. and pcl.li3 == RMISSD:
a = interp.vtmp(300., prof)
b = thermo.wetlift(pe1, tp1, 300.)
pcl.li3 = a - thermo.virtemp(300, b, b)
# Calculate BRN if available
pcl = bulk_rich(pcl, prof)
pcl.bminus = cinh_old
if pcl.bplus == 0: pcl.bminus = 0.
return pcl
def helicity(lower, upper, prof, stu=0, stv=0):
'''
Calculates the relative helicity (m2/s2) of a layer from lower to upper.
If storm-motion vector is supplied, storm-relative helicity, both
positve and negative, is returned.
Inputs
------
lower (float) Bottom level of layer (m, AGL)
upper (float) Top level of layer (m, AGL)
prof (profile object) Profile Object
stu (float; optional) U-component of storm-motion
stv (float; optional) V-component of storm-motion
Returns
-------
phel+nhel (float) Combined Helicity (m2/s2)
phel (float) Positive Helicity (m2/s2)
nhel (float) Negative Helicity (m2/s2)
'''
lower = interp.msl(lower, prof)
upper = interp.msl(upper, prof)
plower = interp.pres(lower, prof)
pupper = interp.pres(upper, prof)
phel = 0
nhel = 0
# Find lower and upper ind bounds for looping
i = 0
while interp.msl(prof.gSndg[i][prof.zind], prof) < lower:
i += 1
lptr = i
if interp.msl(prof.gSndg[i][prof.zind], prof) == lower: lptr += 1
while interp.msl(prof.gSndg[i][prof.zind], prof) <= upper:
i += 1
uptr = i
if interp.msl(prof.gSndg[i][prof.zind], prof) == upper: uptr -= 1
# Integrate from interpolated bottom level to iptr level
sru1, srv1 = interp.components(plower, prof)
sru1 = KTS2MS(sru1 - stu)
srv1 = KTS2MS(srv1 - stv)
# Loop through levels
for i in range(lptr, uptr + 1):
if QC(prof.gSndg[i][prof.uind]) and QC(prof.gSndg[i][prof.vind]):
sru2, srv2 = interp.components(prof.gSndg[i][prof.pind], prof)
sru2 = KTS2MS(sru2 - stu)
srv2 = KTS2MS(srv2 - stv)
lyrh = (sru2 * srv1) - (sru1 * srv2)
if lyrh > 0: phel += lyrh
else: nhel += lyrh
sru1 = sru2
srv1 = srv2
# Integrate from tptr level to interpolated top level
sru2, srv2 = interp.components(pupper, prof)
sru2 = KTS2MS(sru2 - stu)
srv2 = KTS2MS(srv2 - stv)
lyrh = (sru2 * srv1) - (sru1 * srv2)
if lyrh > 0: phel += lyrh
else: nhel += lyrh
return phel + nhel, phel, nhel
def parcelx(lower, upper, pres, temp, dwpt, prof, **kwargs):
'''
Lifts the specified parcel, calculated various levels and parameters from
the profile object. B+/B- are calculated based on the specified layer.
!! All calculations use the virtual temperature correction unless noted. !!
Inputs
------
lower (float) Lower-bound lifting level (hPa)
upper (float) Upper-bound lifting level
pres (float) Pressure of parcel to lift (hPa)
temp (float) Temperature of parcel to lift (C)
dwpt (float) Dew Point of parcel to lift (C)
prof (profile object) Profile Object
Returns
-------
pcl (parcel object) Parcel Object
'''
pcl = Parcel(-1, -1, pres, temp, dwpt)
if 'lplvals' in kwargs: pcl.lplvals = kwargs.get('lplvals')
else:
lplvals = DefineParcel(prof, 5, pres=pres, temp=temp, dwpt=dwpt)
pcl.lplvals = lplvals
if prof.gNumLevels < 1: return pcl
lyre = -1
cap_strength = RMISSD
cap_strengthpres = RMISSD
li_max = RMISSD
li_maxpres = RMISSD
totp = 0.
totn = 0.
tote = 0.
cinh_old = 0.
# See if default layer is specified
if lower == -1:
lower = prof.gSndg[prof.sfc][prof.pind]
pcl.blayer = lower
if upper == -1:
upper = prof.gSndg[prof.gNumLevels-1][prof.pind]
pcl.tlayer = upper
# Make sure that this is a valid layer
if lower > pres:
lower = pres
pcl.blayer = lower
if not QC(interp.vtmp(lower, prof)) or \
not QC(interp.vtmp(upper, prof)):
return RMISSD
# Begin with the Mixing Layer
te1 = interp.vtmp(pres, prof)
pe1 = lower
h1 = interp.hght(pe1, prof)
tp1 = thermo.virtemp(pres, temp, dwpt)
# te1 = tp1
# Lift parcel and return LCL pres (hPa) and LCL temp (c)
pe2, tp2 = thermo.drylift(pres, temp, dwpt)
blupper = pe2 # Define top of layer as LCL pres
h2 = interp.hght(pe2, prof)
te2 = interp.vtmp(pe2, prof)
pcl.lclpres = pe2
pcl.lclhght = interp.agl(h2, prof)
# Calculate lifted parcel theta for use in iterative CINH loop below
# RECALL: lifted parcel theta is CONSTANT from LPL to LCL
theta_parcel = thermo.theta(pe2, tp2, 1000.)
# Environmental theta and mixing ratio at LPL
bltheta = thermo.theta(pres, interp.temp(pres, prof), 1000.)
blmr = thermo.mixratio(pres, dwpt)
# ACCUMULATED CINH IN MIXING LAYER BELOW THE LCL
# This will be done in 10mb increments, and will use the virtual
# temperature correction where possible
pinc = -10
a = int(lower)
b = int(blupper)
for pp in range(a, b, int(pinc)):
pp1 = pp
pp2 = pp + pinc
if pp2 < blupper: pp2 = blupper
dz = interp.hght(pp2, prof) - interp.hght(pp1, prof)
# Calculate difference between Tv_parcel and Tv_environment at top
# and bottom of 10mb layers. Make use of constant lifted parcel
# theta and mixing ratio from LPL to LCL
tv_env_bot = thermo.virtemp(pp1, thermo.theta(pp1,
interp.temp(pp1, prof), 1000.), interp.dwpt(pp1, prof))
tdef1 = (thermo.virtemp(pp1, theta_parcel,
thermo.temp_at_mixrat(blmr, pp1)) - tv_env_bot) / \
(thermo.ctok(tv_env_bot))
tv_env_top = thermo.virtemp(pp2, thermo.theta(pp2,
interp.temp(pp2, prof), 1000.), interp.dwpt(pp2, prof))
tdef2 = (thermo.virtemp(pp2, theta_parcel,
thermo.temp_at_mixrat(blmr, pp2)) - tv_env_top) / \
(thermo.ctok(tv_env_bot))
lyre = G * (tdef1 + tdef2) / 2. * dz
if lyre < 0: totn += lyre
# Move the bottom layer to the top of the boundary layer
if lower > pe2:
lower = pe2
pcl.blayer = lower
# Calculate height of various temperature levels
p0c = temp_lvl(0., prof)
pm10c = temp_lvl(-10., prof)
pm20c = temp_lvl(-20., prof)
pm30c = temp_lvl(-30., prof)
hgt0c = interp.hght(p0c, prof)
hgtm10c = interp.hght(pm10c, prof)
hgtm20c = interp.hght(pm20c, prof)
hgtm30c = interp.hght(pm30c, prof)
pcl.p0c = p0c
pcl.pm10c = pm10c
pcl.pm20c = pm20c
pcl.pm30c = pm30c
pcl.hght0c = hgt0c
pcl.hghtm10c = hgtm10c
pcl.hghtm20c = hgtm20c
pcl.hghtm30c = hgtm30c
# Find lowest observation in layer
i = 0
while prof.gSndg[i][prof.pind] > lower:
if i == prof.gNumLevels-1: break
i += 1
while not QC(prof.gSndg[i][prof.tdind]):
if i == prof.gNumLevels-1: break
i += 1
lptr = i
if prof.gSndg[i][prof.pind] == lower:
if i != prof.gNumLevels-1: lptr += 1
# Find highest observation in layer
i = prof.gNumLevels-1
while prof.gSndg[i][prof.pind] < upper:
if i < lptr: break
i -= 1
uptr = i
if prof.gSndg[i][prof.pind] == upper:
if i > lptr: uptr -= 1
# START WITH INTERPOLATED BOTTOM LAYER
# Begin moist ascent from lifted parcel LCL (pe2, tp2)
pe1 = lower
h1 = interp.hght(pe1, prof)
te1 = interp.vtmp(pe1, prof)
tp1 = thermo.wetlift(pe2, tp2, pe1)
lyre = 0
lyrlast = 0
for i in range(lptr, prof.gNumLevels):
if not QC(prof.gSndg[i][prof.tind]): continue
pe2 = prof.gSndg[i][prof.pind]
h2 = prof.gSndg[i][prof.zind]
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe1, tp1, pe2)
tdef1 = (thermo.virtemp(pe1, tp1, tp1) - te1) / thermo.ctok(te1)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / thermo.ctok(te2)
lyrlast = lyre
lyre = G * (tdef1 + tdef2) / 2. * (h2 - h1)
# Add layer energy to total positive if lyre > 0
if lyre > 0: totp += lyre
# Add layer energy to total negative if lyre < 0, only up to EL
else:
if pe2 > 500.: totn += lyre
# Check for Max LI
mli = thermo.virtemp(pe2, tp2, tp2) - te2
if mli > li_max:
li_max = mli
li_maxpres = pe2
# Check for Max Cap Strength
mcap = te2 - mli
if mcap > cap_strength:
cap_strength = mcap
cap_strengthpres = pe2
tote += lyre
pelast = pe1
pe1 = pe2
h1 = h2
te1 = te2
tp1 = tp2
# Is this the top of the specified layer
if i >= uptr and not QC(pcl.bplus):
pe3 = pe1
h3 = h1
te3 = te1
tp3 = tp1
lyrf = lyre
if lyrf > 0:
pcl.bplus = totp - lyrf
pcl.bminus = totn
else:
pcl.bplus = totp
if pe2 > 500.: pcl.bminus = totn + lyrf
else: pcl.bminus = totn
pe2 = upper
h2 = interp.hght(pe2, prof)
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (h2 - h3)
if lyrf > 0: pcl.bplus += lyrf
else:
if pe2 > 500.: pcl.bminus += lyrf
if pcl.bplus == 0: pcl.bminus = 0.
# Is this the freezing level
if te2 < 0. and not QC(pcl.bfzl):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0.: pcl.bfzl = totp - lyrf
else: pcl.bfzl = totp
if not QC(p0c) or p0c > pe3:
pcl.bfzl = 0
elif QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (hgt0c - h3)
if lyrf > 0: pcl.bfzl += lyrf
# Is this the -10C level
if te2 < -10. and not QC(pcl.wm10c):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0.: pcl.wm10c = totp - lyrf
else: pcl.wm10c = totp
if not QC(pm10c) or pm10c > pcl.lclpres:
pcl.wm10c = 0
elif QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (hgtm10c - h3)
if lyrf > 0: pcl.wm10c += lyrf
# Is this the -20C level
if te2 < -20. and not QC(pcl.wm20c):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0.: pcl.wm20c = totp - lyrf
else: pcl.wm20c = totp
if not QC(pm20c) or pm20c > pcl.lclpres:
pcl.wm20c = 0
elif QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (hgtm20c - h3)
if lyrf > 0: pcl.wm20c += lyrf
# Is this the -30C level
if te2 < -30. and not QC(pcl.wm30c):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0.: pcl.wm30c = totp - lyrf
else: pcl.wm30c = totp
if not QC(pm30c) or pm30c > pcl.lclpres:
pcl.wm30c = 0
elif QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (hgtm30c - h3)
if lyrf > 0: pcl.wm30c += lyrf
# Is this the 3km level
if pcl.lclhght < 3000.:
h = interp.agl(interp.hght(pe2, prof), prof)
if h >= 3000. and not QC(pcl.b3km):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0: pcl.b3km = totp - lyrf
else: pcl.b3km = totp
h2 = interp.msl(3000., prof)
pe2 = interp.pres(h2, prof)
if QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (h2 - h3)
if lyrf > 0: pcl.b3km += lyrf
else: pcl.b3km = 0.
# Is this the 6km level
if pcl.lclhght < 6000.:
h = interp.agl(interp.hght(pe2, prof), prof)
if h >= 6000. and not QC(pcl.b6km):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
lyrf = lyre
if lyrf > 0: pcl.b6km = totp - lyrf
else: pcl.b6km = totp
h2 = interp.msl(6000., prof)
pe2 = interp.pres(h2, prof)
if QC(pe2):
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (h2 - h3)
if lyrf > 0: pcl.b6km += lyrf
else: pcl.b6km = 0.
# LFC Possibility
if lyre >= 0. and lyrlast <= 0.:
tp3 = tp1
te3 = te1
pe2 = pe1
pe3 = pelast
while interp.vtmp(pe3, prof) > thermo.virtemp(pe3,
thermo.wetlift(pe2, tp3, pe3), thermo.wetlift(pe2, tp3, pe3)):
pe3 -= 5
pcl.lfcpres = pe3
pcl.lfchght = interp.agl(interp.hght(pe3, prof), prof)
cinh_old = totn
tote = 0.
pcl.elpres = RMISSD
li_max = RMISSD
if cap_strength < 0.: cap_strength = 0.
pcl.cap = cap_strength
pcl.cappres = cap_strengthpres
# Hack to force LFC to be at least at the LCL
if pcl.lfcpres > pcl.lclpres:
pcl.lfcpres = pcl.lclpres
pcl.lfchght = pcl.lclhght
# EL Possibility
if lyre <= 0. and lyrlast >= 0.:
tp3 = tp1
te3 = te1
pe2 = pe1
pe3 = pelast
while interp.vtmp(pe3, prof) < thermo.virtemp(pe3,
thermo.wetlift(pe2, tp3, pe3), thermo.wetlift(pe2, tp3, pe3)):
pe3 -= 5
pcl.elpres = pe3
pcl.elhght = interp.agl(interp.hght(pe3, prof), prof)
pcl.mplpres = RMISSD
pcl.limax = -li_max
pcl.limaxpress = li_maxpres
# MPL Possibility
if tote < 0. and not QC(pcl.mplpres) and QC(pcl.elpres):
pe3 = pelast
h3 = interp.hght(pe3, prof)
te3 = interp.vtmp(pe3, prof)
tp3 = thermo.wetlift(pe1, tp1, pe3)
totx = tote - lyre
pe2 = pelast
while totx > 0:
pe2 -= 1
te2 = interp.vtmp(pe2, prof)
tp2 = thermo.wetlift(pe3, tp3, pe2)
h2 = interp.hght(pe2, prof)
tdef3 = (thermo.virtemp(pe3, tp3, tp3) - te3) / \
thermo.ctok(te3)
tdef2 = (thermo.virtemp(pe2, tp2, tp2) - te2) / \
thermo.ctok(te2)
lyrf = G * (tdef3 + tdef2) / 2. * (h2 - h3)
totx += lyrf
tp3 = tp2
te3 = te2
pe3 = pe2
pcl.mplpres = pe2
pcl.mplhght = interp.agl(interp.hght(pe2, prof), prof)
# 500 hPa Lifted Index
if prof.gSndg[i][prof.pind] <= 500. and pcl.li5 == RMISSD:
a = interp.vtmp(500., prof)
b = thermo.wetlift(pe1, tp1, 500.)
pcl.li5 = a - thermo.virtemp(500, b, b)
# 300 hPa Lifted Index
if prof.gSndg[i][prof.pind] <= 300. and pcl.li3 == RMISSD:
a = interp.vtmp(300., prof)
b = thermo.wetlift(pe1, tp1, 300.)
pcl.li3 = a - thermo.virtemp(300, b, b)
# Calculate BRN if available
pcl = bulk_rich(pcl, prof)
pcl.bminus = cinh_old
if pcl.bplus == 0: pcl.bminus = 0.
return pcl
def helicity(lower, upper, prof, stu=0, stv=0):
'''
Calculates the relative helicity (m2/s2) of a layer from lower to upper.
If storm-motion vector is supplied, storm-relative helicity, both
positve and negative, is returned.
Inputs
------
lower (float) Bottom level of layer (m, AGL)
upper (float) Top level of layer (m, AGL)
prof (profile object) Profile Object
stu (float; optional) U-component of storm-motion
stv (float; optional) V-component of storm-motion
Returns
-------
phel+nhel (float) Combined Helicity (m2/s2)
phel (float) Positive Helicity (m2/s2)
nhel (float) Negative Helicity (m2/s2)
'''
lower = interp.msl(lower, prof)
upper = interp.msl(upper, prof)
plower = interp.pres(lower, prof)
pupper = interp.pres(upper, prof)
phel = 0
nhel = 0
# Find lower and upper ind bounds for looping
i = 0
while interp.msl(prof.gSndg[i][prof.zind], prof) < lower: i+=1
lptr = i
if interp.msl(prof.gSndg[i][prof.zind], prof) == lower: lptr+=1
while interp.msl(prof.gSndg[i][prof.zind], prof) <= upper: i+=1
uptr = i
if interp.msl(prof.gSndg[i][prof.zind], prof) == upper: uptr-=1
# Integrate from interpolated bottom level to iptr level
sru1, srv1 = interp.components(plower, prof)
sru1 = KTS2MS(sru1 - stu)
srv1 = KTS2MS(srv1 - stv)
# Loop through levels
for i in range(lptr, uptr+1):
if QC(prof.gSndg[i][prof.uind]) and QC(prof.gSndg[i][prof.vind]):
sru2, srv2 = interp.components(prof.gSndg[i][prof.pind], prof)
sru2 = KTS2MS(sru2 - stu)
srv2 = KTS2MS(srv2 - stv)
lyrh = (sru2 * srv1) - (sru1 * srv2)
if lyrh > 0: phel += lyrh
else: nhel += lyrh
sru1 = sru2
srv1 = srv2
# Integrate from tptr level to interpolated top level
sru2, srv2 = interp.components(pupper, prof)
sru2 = KTS2MS(sru2 - stu)
srv2 = KTS2MS(srv2 - stv)
lyrh = (sru2 * srv1) - (sru1 * srv2)
if lyrh > 0: phel += lyrh
else: nhel += lyrh
return phel+nhel, phel, nhel
