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# Copyright (c) 2019, TU Wien
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"""
The grid module implements the asymmetrical GMAO 0.5 x 0.625 grid
used in MERRA2 as a pygeogrids BasicGrid instance.
"""
import numpy as np
from pygeogrids.grids import BasicGrid
[docs]def create_merra_cell_grid():
"""
Function creates the asymmetrical GMAO 0.5 x 0.625 grid as a
BasicGrid instance.
Returns
-------
BasicGrid instance
"""
# define horizontal and vertical resolution of asymmetrical grid
lon_res = 0.625
lat_res = 0.5
# create 361 (lat) x 576 (lon) mesh grid
lon, lat = np.meshgrid(
np.arange(-180, 180, lon_res),
np.arange(-90, 90 + lat_res / 2, lat_res)
)
return BasicGrid(lon.flatten(), lat.flatten()).to_cell_grid(cellsize=5.)