xarray.Dataset.domcfg.zco
- Dataset.domcfg.zco(*args, **kwargs)
Generate NEMO geopotential z-coordinates model levels.
- Parameters
- ppdzmin: float
Minimum thickness for the top layer (units: m)
- pphmax: float
Depth of the last W-level (total depth of the ocean basin) (units: m)
- ppkth: float, default = 0
Model level at which approximately max stretching occurs. Nondimensional > 0, usually of order 1/2 or 2/3 of
jpk
. (0 means no stretching, uniform grid)- ppacr: int, default = 0
Stretching factor, nondimensional > 0. The larger
ppacr
, the smaller the stretching. Values from 3 to 10 are usual. (0 means no stretching, uniform grid)- ppsur, ppa0, ppa1: float, optional
Coefficients controlling distibution of vertical levels (None: compute from
ppdzmin
,pphmax
,ppkth
andppacr
)- ppa2, ppkth2, ppacr2: float, optional
Double tanh stretching function parameters. (None: Double tanh OFF)
- ln_e3_dep: bool, default = True
Logical flag to comp. e3 as fin. diff. (True) oranalyt. (False) (default = True)
- Returns
- Dataset
Describing the 3D geometry of the model
See also
pydomcfg.domzgr.zco.Zco.__call__
Underlying method.
NEMOv4.0
domzgr/zgr_z
subroutine
Notes
Model levels’ depths
z3{T,W}
are defined from analytical function.Model vertical scale factors
e3{T,W}
(i.e., grid cell thickness) can be computed as:analytical derivative of depth function (
ln_e3_dep=False
); for backward compatibility with v3.6.discrete derivative (central-difference) of levels’ depth (
ln_e3_dep=True
). The only possibility from v4.0.
See [1] and equations E.1-4 in the NEMO4 v4 ocean engine manual [2].
References
- 1
Marti, O., Madec, G., and Delecluse, P. (1992), Comment [on “Net diffusivity in ocean general circulation models with nonuniform grids” by F. L. Yin and I. Y. Fung], J. Geophys. Res., 97( C8), 12763– 12766, http://doi.org/10.1029/92JC00306.
- 2
Madec Gurvan, Romain Bourdallé-Badie, Jérôme Chanut, Emanuela Clementi, Andrew Coward, Christian Ethé, … Guillaume Samson. (2019, October 24). NEMO ocean engine (Version v4.0). Notes Du Pôle De Modélisation De L’institut Pierre-simon Laplace (IPSL). Zenodo. http://doi.org/10.5281/zenodo.3878122