wrf.uvmet¶
-
wrf.
uvmet
(u, v, lat, lon, cen_long, cone, meta=True, units='m s-1')¶ Return the u,v components of the wind rotated to earth coordinates.
The leftmost dimension of the returned array represents two different quantities:
- return_val[0,…] will contain U
- return_val[1,…] will contain V
This is the raw computational algorithm and does not extract any variables from WRF output files. Use
wrf.getvar()
to both extract and compute diagnostic variables.Parameters: - u (
xarray.DataArray
ornumpy.ndarray
) –The u component of the wind [m s-1]. This variable can be staggered or unstaggered, but must be at least two dimensions. If staggered, the rightmost dimensions are south_north x west east.
If staggered, the rightmost dimensions are south_north x west_east_stag.
Note
This variable must be supplied as a
xarray.DataArray
in order to copy the dimension names to the output. Otherwise, default names will be used. - v (
xarray.DataArray
ornumpy.ndarray
) –The v component of the wind [m s-1]. This variable can be staggered or unstaggered, but must be at least two dimensions. If staggered, the rightmost dimensions are south_north x west east.
If staggered, the rightmost dimensions are south_north_stag x west_east.
- lat (
xarray.DataArray
ornumpy.ndarray
) –The latitude array.
This array can either be:
- two-dimensional of size south_north x west_east.
- multi-dimensional with the same number of dimensions as u and v, but with rightmost dimensions south_north x west_east and the same leftmost dimensions as u and v
- multi-dimensional with one fewer dimensions as u and v, with rightmost dimensions south_north x west_east and the same leftmost dimensions as u and v, minus the third-from-the-right dimension of u and v.
Note
This variable must also be supplied as a
xarray.DataArray
in order to copy the dimension names to the output. Otherwise, default names will be used. - lon (
xarray.DataArray
ornumpy.ndarray
) –The longitude array.
This array can either be:
- two-dimensional of size south_north x west_east.
- multi-dimensional with the same number of dimensions as u and v, but with rightmost dimensions south_north x west_east and the same leftmost dimensions as u and v
- multi-dimensional with one fewer dimensions as u and v, with rightmost dimensions south_north x west_east and the same leftmost dimensions as u and v, minus the third-from-the-right dimension of u and v.
- cen_long (
float
) – The standard longitude for the map projection. - cone (
float
) –The cone factor used for the map project. If the projection is not a conic projection, the cone is simply 1.0. For conic projections, the cone factor is given by:
if((fabs(true_lat1 - true_lat2) > 0.1) and (fabs(true_lat2 - 90.) > 0.1)): cone = (log(cos(true_lat1*radians_per_degree)) - log(cos(true_lat2*radians_per_degree))) cone = (cone / (log(tan((45.-fabs(true_lat1/2.))*radians_per_degree)) - log(tan((45.-fabs(true_lat2/2.))*radians_per_degree)))) else: cone = sin(fabs(true_lat1)*radians_per_degree)
- meta (
bool
) – Set to False to disable metadata and returnnumpy.ndarray
instead ofxarray.DataArray
. Default is True. - units (
str
) – The desired units. Refer to thegetvar()
product table for a list of available units for ‘uvmet’. Default is ‘m s-1’.
Warning
The input arrays must not contain any missing/fill values or
numpy.nan
values.Returns: The u,v components of the wind rotated to earth coordinates. The leftmost dimension size is 2, for u and v. If xarray is enabled and the meta parameter is True, then the result will be an xarray.DataArray
object. Otherwise, the result will be anumpy.ndarray
object with no metadata.Return type: xarray.DataArray
ornumpy.ndarray
See also