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[python #NHC-140532]: Satellite reprojections

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  • Subject: [python #NHC-140532]: Satellite reprojections
  • Date: Wed, 01 Apr 2020 14:02:36 -0600
Greetings!

The following code is able to re-project and runs in less than a minute within 
a notebook on my mac on Python 3.8:

    import cartopy.crs as ccrs
    import cartopy.feature as cfeature
    import matplotlib.pyplot as plt
    import metpy
    import numpy as np
    from siphon.catalog import TDSCatalog

    # Access data using Siphon
    cat = 
TDSCatalog('https://thredds.ucar.edu/thredds/catalog/satellite/goes/east/products/CloudAndMoistureImagery/CONUS/Channel02/current/catalog.xml')
    nc = cat.datasets[0].remote_access(use_xarray=True)
    data = nc.metpy.parse_cf('Sectorized_CMI')

    # Set up our target projection
    target = ccrs.LambertConformal(central_longitude=-80, 
standard_parallels=[35])

    # Create the figure, making sure to set extent before plotting
    fig = plt.figure(figsize=(10, 10))
    ax = fig.add_subplot(1, 1, 1, projection=target)
    ax.set_extent((-85, -75, 35, 45), crs=ccrs.Geodetic())

    # Plot image and add some map features
    ax.imshow(np.sqrt(data), extent=(data.metpy.x[0], data.metpy.x[-1], 
data.metpy.y[0], data.metpy.y[-1]),
              origin='lower', cmap='Greys_r', 
transform=subset.metpy.cartopy_crs)
    ax.add_feature(cfeature.COASTLINE.with_scale('10m'), edgecolor='orange')
    ax.add_feature(cfeature.LAKES.with_scale('10m'), edgecolor='cyan', 
facecolor='none')

Does this work for you? If there's something significantly different that your 
code is doing, can you share it so I can see what's going on?

Hope this helps,

Ryan

> Hi there-
> 
> I have a question regarding the satellite data found on the threads data 
> server.
> 
> I would like to begin building products for our universtity department’s web 
> site, but I have been struggling mightily when trying to take the NEW (not 
> GINI) satellite data and reproject it (for example, taking the CONUS view 
> from GOES-E and placing it into a LambertConformal projection of the 
> Northeast US (using cartopy).
> 
> Any attempt to reproject the data on the unidata threads server is never 
> completing …
> 
> Is there a guide for this? I am developing w/ jupyter, but am open to any 
> ideas to make this work.


Ticket Details
===================
Ticket ID: NHC-140532
Department: Support Python
Priority: Low
Status: Closed
===================
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