Note

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ICON Cell-centered streamplots

This example draws streamlines from ICON cell-centered vector winds with easyclimate.plot.icon.plot_cell_streamplot.

The ICON vectors are interpolated to a regular grid inside the requested longitude-latitude window before calling Matplotlib’s streamplot machinery.

import xarray as xr
import numpy as np
import cartopy.crs as ccrs
import matplotlib.pyplot as plt
import easyclimate as ecl

from easyclimate.plot.icon import plot_cell_streamplot

Open a sample ICON model-level file and select the horizontal wind components stored on cell centers.

data = ecl.open_tutorial_dataset("icon_native_ml_20080909T000000Z")
u = data.u
v = data.v
u

icon_native_ml_20080909T000000Z.nc ━━━━━━━ 100.0% • 1.8/1.8 • 20.2     • 0:00:00
                                                    MB        MB/s

<xarray.DataArray 'u' (ncells: 81920)> Size: 328kB
[81920 values with dtype=float32]
Coordinates:
    clon     (ncells) float64 655kB ...
    clat     (ncells) float64 655kB ...
    time     float64 8B ...
    height   float64 8B ...
Dimensions without coordinates: ncells
Attributes:
    standard_name:                eastward_wind
    long_name:                    Zonal wind
    units:                        m s-1
    param:                        2.2.0
    CDI_grid_type:                unstructured
    number_of_grid_in_reference:  1


Draw streamlines over a regional window on plain Matplotlib axes.

fig, ax = plt.subplots()
q = plot_cell_streamplot(
    data, u, v,
    ax=ax,

    lon_min=140,
    lon_max=220,
    lat_min=25,
    lat_max=70,
)

ax.set_title("JW Wave Wind Field\n(height = 19, plot_cell_streamplot)")
JW Wave Wind Field (height = 19, plot_cell_streamplot)
Text(0.5, 1.0, 'JW Wave Wind Field\n(height = 19, plot_cell_streamplot)')

Draw streamlines on a shifted PlateCarree map. The helper keeps the visible window aligned with the requested longitude-latitude bounds. sphinx_gallery_thumbnail_number = -1

fig, ax = plt.subplots(
    subplot_kw={"projection": ccrs.PlateCarree(180)}
)
q = plot_cell_streamplot(
    data, u, v,
    ax=ax,

    lon_min=140,
    lon_max=220,
    lat_min=25,
    lat_max=70,

    transform=ccrs.PlateCarree(),
)

ax.set_title("JW Wave Wind Field\n(height = 19, plot_cell_streamplot)")
ax.coastlines(resolution="110m", linewidth=0.6, color="b")
ax.gridlines(draw_labels=True, alpha=0)
JW Wave Wind Field (height = 19, plot_cell_streamplot)
<cartopy.mpl.gridliner.Gridliner object at 0x79225c97d6a0>

Total running time of the script: (0 minutes 6.222 seconds)