def compute_OMEGA(ivar, inc, onc, bf, plevs):
"""
Calculate approximate omega, based on vertical velocity w (dz/dt).
It is approximate because it cannot take into account the vertical
motion of pressure surfaces.
"""
temp = bf.temp
pres = bf.pres_field
qvapor = bf.qvapor
wobj = inc.variables["W"]
vel_w = de_stagger(wobj, wobj[:])
grav = 9.81
rgas = 287.04
eps = 0.622
omega = -grav*pres/(rgas*((temp*(eps + qvapor))/(eps*(1.0 + qvapor))))*vel_w
ovardata = f90.interp(tr(omega), tr(bf.pres_field), plevs, tr(bf.psfc),
tr(bf.hgt), tr(bf.temp), tr(bf.qvapor), linlog=1,
extrapolate=1, geopt=False, missing=1.e36)
dim_list = ["Time","num_metgrid_levels", "south_north", "west_east"]
ovarobj = onc.createVariable(ivar, 'float32', dim_list, zlib=True, complevel=4, shuffle=True)
ovarobj[:] = tr(ovardata)
ovarobj.FieldType = 104
ovarobj.MemoryOrder = "XYZ"
ovarobj.description = "Approximate omega"
ovarobj.units = "Pa s-1"
ovarobj.stagger = ""
ovarobj.coordinates = "XLONG XLAT"
return onc
def compute_GHT(ivar, inc, onc, bf, plevs):
ovardata = f90.interp(tr(bf.ght),
tr(bf.pres_field),
plevs,
tr(bf.psfc),
tr(bf.hgt),
tr(bf.temp),
tr(bf.qvapor),
linlog=1,
extrapolate=1,
geopt=True,
missing=1.e36)
dim_list = ["Time", "num_metgrid_levels", "south_north", "west_east"]
ovarobj = onc.createVariable(ivar,
'float32',
dim_list,
zlib=True,
complevel=4,
shuffle=True)
ovarobj[:] = tr(ovardata)
ovarobj.FieldType = 104
ovarobj.MemoryOrder = "XZY"
ovarobj.description = "Geopotential Height"
ovarobj.units = "m2s-2"
ovarobj.stagger = "-"
ovarobj.coordinates = "XLONG XLAT"
return onc
def interp2plevs(ivar, inc, onc, bf, plevs):
ivarobj = inc.variables[ivar]
ivardata = ivarobj[:]
#
# Check if the variable is staggered and de-stagger it if necessary
#
if is_staggered(ivarobj):
logging.debug( "Variable %s is staggered, de-staggering" % ivar )
ivardata = de_stagger(ivarobj, ivardata)
#
# Call fortran interpolation routine
#
logging.debug( "Calling interpolation routine" )
ovardata = f90.interp(tr(ivardata), tr(bf.pres_field), plevs, tr(bf.psfc), tr(bf.hgt), tr(bf.temp), tr(bf.qvapor),
linlog=1, extrapolate=1, geopt=False, missing=1.e36)
#
# Create the output variable and add data and attributes
#
ovarobj = onc.createVariable(ivar, ivarobj.dtype, ["Time", "num_metgrid_levels", "south_north", "west_east"], zlib=True, complevel=4, shuffle=True)
ovarobj[:] = tr(ovardata)
for attrname, attrvalue in ivarobj.__dict__.items():
if attrname == "stagger":
ovarobj.setncattr(attrname, "")
continue
ovarobj.setncattr(attrname, attrvalue)
return onc
def compute_RH(ivar, inc, onc, bf, plevs):
ovardata = f90.interp(tr(bf.rh),
tr(bf.pres_field),
plevs,
tr(bf.psfc),
tr(bf.hgt),
tr(bf.temp),
tr(bf.qvapor),
linlog=1,
extrapolate=1,
geopt=False,
missing=1.e36)
ovarobj = onc.createVariable(
ivar,
'float32', ["Time", "num_metgrid_levels", "south_north", "west_east"],
zlib=True,
complevel=4,
shuffle=True)
ovarobj[:] = tr(ovardata)
ovarobj.FieldType = 104
ovarobj.MemoryOrder = "XZY"
ovarobj.description = "Relative Humidity"
ovarobj.units = "%"
ovarobj.stagger = "-"
ovarobj.coordinates = "XLONG XLAT"
return onc
def compute_RH(ivar, inc, onc, bf, plevs):
ovardata = f90.interp(tr(bf.rh), tr(bf.pres_field), plevs, tr(bf.psfc), tr(bf.hgt), tr(bf.temp), tr(bf.qvapor),
linlog=1, extrapolate=1, geopt=False, missing=1.e36)
ovarobj = onc.createVariable(ivar, 'float32', ["Time", "num_metgrid_levels", "south_north", "west_east"], zlib=True, complevel=4, shuffle=True)
ovarobj[:] = tr(ovardata)
ovarobj.FieldType = 104 ;
ovarobj.MemoryOrder = "XZY" ;
ovarobj.description = "Relative Humidity" ;
ovarobj.units = "%" ;
ovarobj.stagger = "-" ;
ovarobj.coordinates = "XLONG XLAT" ;
return onc
def compute_WSPD(ivar, inc, onc, bf, plevs):
# 3D wind speed
# Need to destagger 3D winds
uobj = inc.variables["U"]
u = de_stagger(uobj, uobj[:])
vobj = inc.variables["V"]
v = de_stagger(vobj, vobj[:])
wspd = np.sqrt(u**2 + v**2)
ovardata = f90.interp(tr(wspd), tr(bf.pres_field), plevs, tr(bf.psfc),
tr(bf.hgt), tr(bf.temp), tr(bf.qvapor), linlog=1,
extrapolate=1, geopt=False, missing=1.e36)
dim_list = ["Time", "num_metgrid_levels", "south_north", "west_east"]
ovarobj = onc.createVariable(ivar, 'float32', dim_list, zlib=True,
complevel=4, shuffle=True)
ovarobj[:] = tr(ovardata)
ovarobj.FieldType = 104 ;
ovarobj.MemoryOrder = "XZY" ;
ovarobj.description = "Wind speed" ;
ovarobj.units = "m s-1" ;
ovarobj.stagger = "-" ;
ovarobj.coordinates = "XLONG XLAT" ;
return onc
