Add GLM + ABI example

examples/GOES_ABI_GLM.py

@@ -0,0 +1,114 @@
+"""
+======================
+GOES ABI + GLM example
+======================
+
+This example plots the most recent GOES-16 data with an overlay of the current
+GOES-16 Geostationary Lightning Mapper flash extent density.
+"""
+
+from datetime import datetime
+import json
+import urllib.request
+
+import cartopy.crs as ccrs
+import cartopy.feature as cfeature
+from matplotlib import patheffects
+import matplotlib.pyplot as plt
+from matplotlib.colors import Normalize
+import metpy  # noqa: F401
+import metpy.calc as mpcalc
+from metpy.plots.ctables import registry
+from metpy.units import units
+import numpy as np
+from siphon.catalog import TDSCatalog
+import xarray as xr
+from xarray.backends import NetCDF4DataStore
+
+# e.g. OR_GLM-L2-GLMC-M3_G16_s20191930223000_e20191930224000_c20191930224350.nc
+# leave off last char (13 not 14), to leave off 1/10 s part
+goes_start_regex =  r'_s(?P<strptime>\d{13})'
+goes_strptime = '%Y%j%H%M%S'
+
+def get_glm_image(date=datetime.utcnow(), region='CONUS'):
+    """Return dataset of GOES-16 GLM data."""
+    cat = TDSCatalog('https://thredds-test.unidata.ucar.edu/thredds/catalog/satellite/goes/'
+                     'east/products/GeostationaryLightningMapper/{}/{:%Y%m%d}/'
+                     'catalog.xml'.format(region, date))
+    ds = cat.datasets.filter_time_nearest(date, regex=goes_start_regex,
+                strptime=goes_strptime)
+    ds = ds.remote_access(service='CdmRemote', use_xarray=True)
+    return ds
+
+
+def get_goes_image(date=datetime.utcnow(), channel=8, region='CONUS'):
+    """Return dataset of GOES-16 data."""
+    cat = TDSCatalog('https://thredds.ucar.edu/thredds/catalog/satellite/goes/east/products/'
+                     'CloudAndMoistureImagery/{}/Channel{:02d}/{:%Y%m%d}/'
+                     'catalog.xml'.format(region, channel, date))
+    ds = cat.datasets.filter_time_nearest(date, regex=goes_start_regex,
+                strptime=goes_strptime)
+    ds = ds.remote_access(service='OPENDAP')
+    # ••• Change this to xarray direct, too? •••
+    ds = NetCDF4DataStore(ds)
+    ds = xr.open_dataset(ds)
+    return ds
+
+# lat_lon_box = [-124.5, -105, 38.5, 50]
+
+ds = get_goes_image(channel=14)
+ds_glm = get_glm_image()
+
+# Parse out the projection data from the satellite files
+dat = ds.metpy.parse_cf('Sectorized_CMI')
+proj = dat.metpy.cartopy_crs
+dat_glm = ds_glm.metpy.parse_cf('flash_extent_density')
+proj_glm = dat_glm.metpy.cartopy_crs
+
+fig = plt.figure(figsize=(1.375 * 40, 40))
+ax = fig.add_subplot(1, 1, 1, projection=proj)
+
+def plot_image(dat, ax, cmap='WVCIMSS_r', cmap_range=(195,265)):
+    # Pull out what we need from the GOES netCDF file
+    x = dat['x']
+    y = dat['y']
+
+    # Make the plot
+    plt.subplots_adjust(left=0, bottom=0, right=1, top=1, wspace=0, hspace=0)
+
+    try:
+        mpl_norm, mpl_cmap = registry.get_with_range(cmap, *cmap_range)
+    except KeyError:
+        # If it's not in the MetPy registry, revert to ordinary matplotlib
+        mpl_norm, mpl_cmap = Normalize(*cmap_range), cmap 
+
+    im = ax.imshow(dat, extent=(x.min(), x.max(), y.min(), y.max()),
+                   origin='upper')
+    im.set_cmap(mpl_cmap)
+    im.set_norm(mpl_norm)
+
+plot_image(dat, ax, cmap='gray', cmap_range=(-70+273.5,40+273.5))
+plot_image(dat_glm, ax, cmap='YlOrRd', cmap_range=(0,32))           
+
+ax.add_feature(cfeature.BORDERS, linewidth=8, edgecolor='black')
+ax.add_feature(cfeature.COASTLINE, linewidth=8, edgecolor='black')
+ax.add_feature(cfeature.STATES.with_scale('50m'), linestyle='-',
+               edgecolor='black', linewidth=4)
+
+timestamp = datetime.strptime(ds.start_date_time, '%Y%j%H%M%S')
+timestamp_glm = datetime.strptime(ds_glm.time_coverage_start, '%Y-%m-%dT%H:%M:%SZ')
+abi_label = 'ABI Ch 14: '+timestamp.strftime('%d %B %Y %H%MZ')
+glm_label = 'GLM FED: '+timestamp_glm.strftime('%d %B %Y %H%MZ')
+
+text_time = ax.text(0.01, 0.01, abi_label,
+                    horizontalalignment='left', transform=ax.transAxes,
+                    color='white', fontsize=72, weight='bold')
+text_time_glm = ax.text(0.01, 0.05, glm_label,
+                    horizontalalignment='left', transform=ax.transAxes,
+                    color='white', fontsize=72, weight='bold')
+
+outline_effect = [patheffects.withStroke(linewidth=15, foreground='black')]
+text_time.set_path_effects(outline_effect)
+text_time_glm.set_path_effects(outline_effect)
+
+plt.show()