MPAS

Model description

MPAS is an atmospheric model that consists of an atmospheric fluid-flow solver (the dynamical core) and a subset of the Advanced Research WRF (ARW) model atmospheric physics. The dynamical core solves the fully compressible non-hydrostatic equations of motion. MPAS uses an unstructured centroidal Voronoi mesh (grid, or tessellation) and C-grid staggering of the state variables as the basis for the horizontal discretization in the fluid-flow solver. For a more detailed description, see Skamarock et al. 2012.

Contact:
Falko Judt, National Center for Atmospheric Research (NCAR), USA

Data structure

Note

Use: cdo -setgrid,mpas:GRIDFILE INFILE OUTFILE

to set the grid. Use get_dyamond_winter MPAS.*grid to get the 3.75km grid file, and get_dyamond_summer MPAS.*grid to get the 7.5km grid file.

Horizontal

For DYAMOND, MPAS employs the following meshes:

Global mean mesh spacing	Number of grid columns
15 km	2,621,442
7.5 km	10,485,762
3.75 km	41,943,042

Vertical

The number of vertical levels is 75 (csv file).

Data access

History Files, Output Interval: PT03H

Output will be written for all levels.

Variable	Description
uReconstructZonal	zonal component of horizontal velocity
vReconstructMeridional	meridional component of horizontal velocity
w	vertical velocity
temperature	actual temperature
pressure	pressure
qv	water vapor mixing ratio
qc	cloud water mixing ratio
qi	ice mixing ratio
qr	rain water mixing ratio
qs	snow mixing ratio
qg	graupel mixing ratio
ni	cloud ice number concentration
nr	rain number concentration
skintemp	ground or water surface temperature
sst	sea-surface temperature
snow	snow water equivalent
snowh	physical snow depth
vegfra	vegetation fraction
sh2o	soil equivalent liquid water
smois	soil moisture
tslb	soil layer temperature

Diagnostics Files, Output Interval: PT15M

Variable	Description
taux	surface zonal momentum flux, in N m^{-2}
tauy	surface meridional momentum flux, in N m^{-2}
olrtoa	top-of-atmosphere outgoing longwave radiation flux, in W m^{-2}
cldcvr	cloud cover (max of 3D field cloudfraction along vertical)
vert_int_qv	vertically integrated water vapor mixing ratio, in kg m^{-2}
vert_int_qc	vertically integrated cloud water mixing ratio, in kg m^{-2}
vert_int_qr	vertically integrated rain mixing ratio, in kg m^{-2}
vert_int_qi	vertically integrated ice mixing ratio, in kg m^{-2}
vert_int_qs	vertically integrated snow mixing ratio, in kg m^{-2}
vert_int_qg	vertically integrated graupel mixing ratio, in kg m^{-2}
refl10cm_1km	diagnosed 10 cm radar reflectivity at 1 km AGL, in dBZ
precipw	precipitable water, in kg m^{-2}
u10	10-meter zonal wind, in m s^{-1}
v10	10-meter meridional wind, in m s^{-1}
q2	2-meter specific humidity, in kg kg^{-1}
t2m	2-meter temperature, in K
th2m	2-meter potential temperature, in K
mslp	mean sea-level pressure, in Pa
relhum_200hPa	relative humidity at 200 hPa, in %
relhum_250hPa	relative humidity at 250 hPa, in %
relhum_500hPa	relative humidity at 500 hPa, in %
relhum_700hPa	relative humidity at 700 hPa, in %
relhum_850hPa	relative humidity at 850 hPa, in %
relhum_925hPa	relative humidity at 925 hPa, in %
dewpoint_200hPa	dewpoint temperature at 200 hPa, in K
dewpoint_250hPa	dewpoint temperature at 250 hPa, in K
dewpoint_500hPa	dewpoint temperature at 500 hPa, in K
dewpoint_700hPa	dewpoint temperature at 700 hPa, in K
dewpoint_850hPa	dewpoint temperature at 850 hPa, in K
dewpoint_925hPa	dewpoint temperature at 925 hPa, in K
temperature_200hPa	temperature at 200 hPa, in K
temperature_250hPa	temperature at 250 hPa, in K
temperature_500hPa	temperature at 500 hPa, in K
temperature_700hPa	temperature at 700 hPa, in K
temperature_850hPa	temperature at 850 hPa, in K
temperature_925hPa	temperature at 925 hPa, in K
height_200hPa	geometric height at 200 hPa, in m
height_250hPa	geometric height at 250 hPa, in m
height_500hPa	geometric height at 500 hPa, in m
height_700hPa	geometric height at 700 hPa, in m
height_850hPa	geometric height at 850 hPa, in m
height_925hPa	geometric height at 925 hPa, in m
uzonal_200hPa	zonal wind at 200 hPa, in m/s
uzonal_250hPa	zonal wind at 250 hPa, in m/s
uzonal_500hPa	zonal wind at 500 hPa, in m/s
uzonal_700hPa	zonal wind at 700 hPa, in m/s
uzonal_850hPa	zonal wind at 850 hPa, in m/s
uzonal_925hPa	zonal wind at 925 hPa, in m/s
umeridional_200hPa	meridional wind at 200 hPa, in m/s
umeridional_250hPa	meridional wind at 250 hPa, in m/s
umeridional_500hPa	meridional wind at 500 hPa, in m/s
umeridional_700hPa	meridional wind at 700 hPa, in m/s
umeridional_850hPa	meridional wind at 850 hPa, in m/s
umeridional_925hPa	meridional wind at 925 hPa, in m/s
w_200hPa	vertical velocity at 200 hPa, in m/s
w_250hPa	vertical velocity at 250 hPa, in m/s
w_500hPa	vertical velocity at 500 hPa, in m/s
w_700hPa	vertical velocity at 700 hPa, in m/s
w_850hPa	vertical velocity at 850 hPa, in m/s
w_925hPa	vertical velocity at 925 hPa, in m/s
omega_200hPa	pressure velocity at 200 hPa, in Pa s^{-1}
omega_250hPa	pressure velocity at 250 hPa, in Pa s^{-1}
omega_500hPa	pressure velocity at 500 hPa, in Pa s^{-1}
omega_700hPa	pressure velocity at 700 hPa, in Pa s^{-1}
omega_850hPa	pressure velocity at 850 hPa, in Pa s^{-1}
omega_925hPa	pressure velocity at 925 hPa, in Pa s^{-1}
vorticity_200hPa	relative vorticity at 200 hPa, in s^{-1}
vorticity_250hPa	relative vorticity at 250 hPa, in s^{-1}
vorticity_500hPa	relative vorticity at 500 hPa, in s^{-1}
vorticity_700hPa	relative vorticity at 700 hPa, in s^{-1}
vorticity_850hPa	relative vorticity at 850 hPa, in s^{-1}
vorticity_925hPa	relative vorticity at 925 hPa, in s^{-1}
cape	convective available potential energy (surface parcel), in J kg^{-1}
cin	convective inhibition (surface parcel), in J kg^{-1}
acswupb	accumulated all-sky upward surface shortwave radiation flux, in J m^{-2}
acswdnb	accumulated all-sky downward surface shortwave radiation flux, in J m^{-2}
acswnetb	accumulated all-sky net surface shortwave radiation flux, in J m^{-2}
acswdnt	accumulated all-sky downward TOA shortwave radiation flux, in J m^{-2}
acswnett	accumulated all-sky net TOA shortwave radiation, in J m^{-2}
aclwupb	accumulated all-sky upward surface longwave radiation flux, in J m^{-2}
aclwdnb	accumulated all-sky downward surface longwave radiation flux, in J m^{-2}
aclwnetb	accumulated all-sky net surface longwave radiation, in J m^{-2}
aclwupt	accumulated all-sky upward surface longwave radiation flux, in J m^{-2}
aclwdnt	accumulated clear-sky downward surface longwave radiation flux, in J m^{-2}
aclwnett	accumulated all-sky net TOA longwave radiation flux, in J m^{-2}
rainc	accumulated convective precipitation, in mm
rainnc	accumulated total grid-scale precipitation, in mm

Initialisation and Boundary conditions

Soil Initialisation

Soil initialisation is done via ERA-5.

Input Data

Input data are generated from ERA-5.

Treatment of SST and Sea Ice

MPAS uses the provided IFS data (7 day means).