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GRIB - ERA5 Quasi Biennial Oscillation on Vertical Hovmoeller
# (C) Copyright 2017- ECMWF.
#
# This software is licensed under the terms of the Apache Licence Version 2.0
# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
#
# In applying this licence, ECMWF does not waive the privileges and immunities
# granted to it by virtue of its status as an intergovernmental organisation
# nor does it submit to any jurisdiction.
#
import metview as mv
# getting data
use_cds = False
filename = "u_era5_mnth_strato.grib"
# getting forecast data from CDS
if use_cds:
import cdsapi
c = cdsapi.Client()
c.retrieve(
"reanalysis-era5-pressure-levels-monthly-means",
{
"product_type": "monthly_averaged_reanalysis",
"variable": "u_component_of_wind",
"pressure_level": [70, 50, 30, 20, 10, 7],
"year": [1990, 1991, 1992, 1993, 1994],
"month": list(range(13)),
"day": "01",
"time": "00:00",
"area": [30, -180, -30, 180],
"grid": [1, 1],
"format": "grib",
},
filename,
)
g = mv.read(filename)
# read data from file
else:
if mv.exist(filename):
g = mv.read(filename)
else:
g = mv.gallery.load_dataset(filename)
# define time axis
time_axis = mv.maxis(
axis_type="date",
axis_date_type="months",
axis_years_label_quality="high",
axis_years_label_height=0.5,
axis_months_label_quality="high",
axis_months_label_height=0.3,
axis_days_label="off",
)
# define vertical axis
vertical_axis = mv.maxis(
axis_tick_label_height=0.4, axis_title_text="Pressure (hPa)", axis_title_height=0.5
)
# define view
view = mv.mhovmoellerview(
type="vertical_hovm",
area=[5, -180, -5, 180], # N,W,S,E
bottom_level=70,
top_level=7,
time_axis=time_axis,
vertical_axis=vertical_axis,
)
# define contour shading
cont_shade = mv.mcont(
legend="on",
contour="off",
contour_level_selection_type="interval",
contour_shade_max_level=45,
contour_shade_min_level=-45,
contour_interval=5,
contour_label="off",
contour_shade="on",
contour_shade_colour_method="palette",
contour_shade_method="area_fill",
contour_shade_palette_name="colorbrewer_RdYlBu_18",
)
# define contouring for zero isoline
cont_zero = mv.mcont(
contour_line_style="dash",
contour_line_thickness=4,
contour_line_colour="charcoal",
contour_highlight="off",
contour_max_level=0,
contour_min_level=0,
)
# define legend
legend = mv.mlegend(legend_text_font_size=0.3)
# define the output plot file
mv.setoutput(mv.pdf_output(output_name="qbo_era5_vertical_hovmoeller"))
# generate plot
mv.plot(view, g, cont_shade, cont_zero, legend)