mon = ds['mon'].values topo = dat.get_ps_clim(lat, lon) / 100 topo.units = 'hPa' # ---------------------------------------------------------------------- # Correct for topography u_orig = u u = dat.correct_for_topography(u_orig, topo) # ---------------------------------------------------------------------- # Integrated vertically dp/g # DataArray u_int = int_pres(u, pdim=-3) # ndarray u_int2 = int_pres(u.values, plev*100, pdim=-3) p0=1e5 g = constants.g.values scale = g/p0 m = 7 k = 5 cint=2 plt.figure(figsize=(7,10)) plt.subplot(311) ap.contourf_latlon(u[m,k], clev=cint)
mon = ds['mon'].values topo = dat.get_ps_clim(lat, lon) / 100 topo.units = 'hPa' # ---------------------------------------------------------------------- # Correct for topography u_orig = u u = dat.correct_for_topography(u_orig, topo) # ---------------------------------------------------------------------- # Integrated vertically dp/g # DataArray u_int = int_pres(u, pdim=-3) # ndarray u_int2 = int_pres(u.values, plev * 100, pdim=-3) p0 = 1e5 g = constants.g.values scale = g / p0 m = 7 k = 5 cint = 2 plt.figure(figsize=(7, 10)) plt.subplot(311) ap.contourf_latlon(u[m, k], clev=cint)
ap.contour_latpres(vbar, clev=0.5) t, k = 0, 4 plt.figure(figsize=(7,8)) plt.subplot(211) ap.pcolor_latlon(u[t,k]) plt.subplot(212) ap.pcolor_latlon(v[t,k]) # ---------------------------------------------------------------------- # Moisture fluxes uq = u * q vq = v * q uq_int = dat.int_pres(uq, pdim=-3) vq_int = dat.int_pres(vq, pdim=-3) t, k = 0, 4 plt.figure(figsize=(7,8)) plt.subplot(211) ap.pcolor_latlon(uq[t,k]) plt.subplot(212) ap.pcolor_latlon(vq[t,k]) plt.figure(figsize=(7,8)) plt.subplot(211) ap.pcolor_latlon(uq_int[t]) plt.subplot(212) ap.pcolor_latlon(vq_int[t])
def moisture_flux_conv(uq,
vq,
lat=None,
lon=None,
plev=None,
pdim=-3,
pmin=0,
pmax=1e6,
return_comp=False,
already_int=False):
"""Return the vertically integrated moisture flux convergence.
Parameters
----------
uq : ndarray or xray.DataArray
Zonal moisture flux, with latitude as the second-last dimension,
longitude as the last dimension.
i.e. zonal wind (m/s) * specific humidity (kg/kg)
If already_int is True, then uq is already vertically integrated.
Otherwise, uq is on vertical pressure levels.
vq : ndarray or xray.DataArray
Meridional moisture flux, with latitude as the second-last dimension,
longitude as the last dimension.
i.e. meridional wind (m/s) * specific humidity (kg/kg)
If already_int is True, then vq is already vertically integrated.
Otherwise, vq is on vertical pressure levels.
lat, lon : ndarray, optional
Latitudes and longitudes in degrees. If omitted, then uq and
vq must be xray.DataArrays and the coordinates are extracted
from them.
plev : ndarray, optional
Pressure levels in Pascals. If omitted, then extracted from
DataArray inputs.
pdim : int, optional
Dimension of pressure levels in uq and vq.
pmin, pmax : float, optional
Lower and upper bounds (inclusive) of pressure levels (Pa)
to include in integration.
return_comp : bool, optional
If True, return additional components, otherwise just total
moisture flux convergence.
already_int : bool, optional
If True, then uq and vq inputs have already been vertically
integrated. Otherwise, the vertical integration is
calculated here.
Returns
-------
If return_comp is False:
mfc : ndarray or xray.DataArray
Vertically integrated moisture flux convergence in mm/day.
If return_comp is True:
mfc, mfc_x, mfc_y, uq_int, vq_int : ndarrays or xray.DataArrays
Vertically integrated moisture flux convergence in mm/day
(total, x- and y- components) and vertically integrated
moisture fluxes.
"""
if already_int:
uq_int, vq_int = uq, vq
else:
uq_int = dat.int_pres(uq, plev, pdim=pdim, pmin=pmin, pmax=pmax)
vq_int = dat.int_pres(vq, plev, pdim=pdim, pmin=pmin, pmax=pmax)
mfc, mfc_x, mfc_y = divergence_spherical_2d(uq_int, vq_int, lat, lon)
# Convert from divergence to convergence, and to mm/day
mfc = -dat.precip_convert(mfc, 'kg/m2/s', 'mm/day')
mfc_x = -dat.precip_convert(mfc_x, 'kg/m2/s', 'mm/day')
mfc_y = -dat.precip_convert(mfc_y, 'kg/m2/s', 'mm/day')
if isinstance(mfc, xray.DataArray):
mfc.name = 'Vertically integrated moisture flux convergence'
mfc.attrs['units'] = 'mm/day'
if return_comp:
return mfc, mfc_x, mfc_y, uq_int, vq_int
else:
return mfc
