NetCDF Ozone Layout 2x2 Example

#Metview Macro

#  **************************** LICENSE START ***********************************
# 
#  Copyright 2019 ECMWF. This software is distributed under the terms
#  of the Apache License version 2.0. In applying this license, ECMWF does not
#  waive the privileges and immunities granted to it by virtue of its status as
#  an Intergovernmental Organization or submit itself to any jurisdiction.
# 
#  ***************************** LICENSE END ************************************
# 

# read ERA5 monthly mean O3 on 70 hPa
nc = read("era5_ozone_1999.nc")

# this NetCDF data has the following structure:
#
# dimensions:
#	longitude = 1440 ;
#	latitude = 721 ;
#	time = 4 ;
#variables:
#	float longitude(longitude) ;
#	float latitude(latitude) ;
#	int time(time) ;
#		time:units = "hours since 1900-01-01 00:00:00.0" ;
#	short o3(time, latitude, longitude) ;
#		o3:units = "kg kg**-1" ;
#		o3:long_name = "Ozone mass mixing ratio" ;

# define contour shading
cont = mcont(
    legend                      : "on",
    contour                     : "off",
    contour_max_level           : 4E-6,
    contour_min_level           : 5E-7,
    contour_label               : "off",
    contour_shade               : "on",
    contour_shade_colour_method : "palette",
    contour_shade_method        : "area_fill",
    contour_shade_palette_name  : "m_purple_9"
  )

# define coastlines
coastlines = mcoast(
    map_coastline_thickness : 2,
    map_grid_colour         : "RGB(0.349,0.349,0.349)",
    map_label               : "off"
   )

# define goegraphical view
view = geoview(
    map_projection      : "polar_stereographic",
    map_area_definition : "corners",
    map_hemisphere      : "south",
    area                : [-5.23,46.28,-5.72,-132.72],
    coastlines          : coastlines
    )

# create a 2x2 plot layout with the defined geoview
dw = plot_superpage(pages: mvl_regular_layout(view,2,2,1,1,[5,100,10,100]))

# define month names for plot titles
months = ['JAN', 'APR', 'JUL', 'OCT']

# we build the plot object for each map in a loop
p_obj = nil
for i =1 to 4 do
    
    # define netcdf plotting
    vis = netcdf_visualiser(
        netcdf_plot_type            : "geo_matrix",
        netcdf_latitude_variable    : "latitude",
        netcdf_longitude_variable   : "longitude",
        netcdf_value_variable       : "o3",
        netcdf_dimension_setting_method : "index",
        netcdf_dimension_setting    : ["time:" & (i-1)],
        netcdf_data                 : nc
    )
    
    # define title
    title = mtext(
        text_lines : [
            "<netcdf_info variable='o3' attribute='long_name'/> " &
            "[<netcdf_info variable='o3' attribute='units'/>] 70 hPa - 1999 " &
            months[i]],
        text_font_size : 0.3
    )    

    # add current plot definition to the plot object
    p_obj = p_obj & [dw[i], vis, cont, title]

end for

# define output
setoutput(pdf_output(output_name : 'nc_era5_ozone'))

# generate plot
plot(p_obj)

#  **************************** LICENSE START ***********************************
# 
#  Copyright 2019 ECMWF. This software is distributed under the terms
#  of the Apache License version 2.0. In applying this license, ECMWF does not
#  waive the privileges and immunities granted to it by virtue of its status as
#  an Intergovernmental Organization or submit itself to any jurisdiction.
# 
#  ***************************** LICENSE END ************************************
# 

import metview as mv

# read ERA5 monthly mean O3 on 70 hPa
nc = mv.read("era5_ozone_1999.nc")

# this NetCDF data has the following structure:
#
# dimensions:
#	longitude = 1440 ;
#	latitude = 721 ;
#	time = 4 ;
#variables:
#	float longitude(longitude) ;
#	float latitude(latitude) ;
#	int time(time) ;
#		time:units = "hours since 1900-01-01 00:00:00.0" ;
#	short o3(time, latitude, longitude) ;
#		o3:units = "kg kg**-1" ;
#		o3:long_name = "Ozone mass mixing ratio" ;

# define contour shading
cont = mv.mcont(
    legend                      = "on",
    contour                     = "off",
    contour_max_level           = 4E-6,
    contour_min_level           = 5E-7,
    contour_label               = "off",
    contour_shade               = "on",
    contour_shade_colour_method = "palette",
    contour_shade_method        = "area_fill",
    contour_shade_palette_name  = "m_purple_9"
  )

# define coastlines
coastlines = mv.mcoast(
    map_coastline_thickness = 2,
    map_grid_colour         = "RGB(0.349,0.349,0.349)",
    map_label               = "off"
   )

# define goegraphical view
view = mv.geoview(
    map_projection      = "polar_stereographic",
    map_area_definition = "corners",
    map_hemisphere      = "south",
    area                = [-5.23,46.28,-5.72,-132.72],
    coastlines          = coastlines
    )

# create a 2x2 plot layout with the defined geoview
dw = mv.plot_superpage(pages=mv.mvl_regular_layout(view,2,2,1,1,[5,100,10,100]))

# define month names for plot titles
months = ['JAN', 'APR', 'JUL', 'OCT']

# we build the plot object for each map in a loop
p_obj = []
for i in range(4):
    
    # define netcdf plotting
    vis = mv.netcdf_visualiser(
        netcdf_plot_type            = "geo_matrix",
        netcdf_latitude_variable    = "latitude",
        netcdf_longitude_variable   = "longitude",
        netcdf_value_variable       = "o3",
        netcdf_dimension_setting_method = "index",
        netcdf_dimension_setting    = ["time:" + str(i)],
        netcdf_data                 = nc
    )
    
    # define title
    title = mv.mtext(
        text_lines = [
            "<netcdf_info variable='o3' attribute='long_name'/> " +
            "[<netcdf_info variable='o3' attribute='units'/>] 70 hPa - 1999 " +
            months[i]],
        text_font_size = 0.3
    )    

    # add current plot definition to the plot object
    p_obj.append([dw[i], vis, cont, title])


# define output
mv.setoutput(mv.pdf_output(output_name = 'nc_era5_ozone'))

# generate plot
mv.plot(p_obj)