JMA Himawari-8 True Color Red-Green-Blue (RGB) images created using Geo2Grid (above) displayed the gray to tan hues of a narrow west-to-east oriented volcanic ash cloud following an eruption of Mount Sinabung on 10 August 2020.

A sequence of Terra MODIS False Color RGB, Ash Probability, Ash Loading, Ash Height and Ash Effective Radius products from the NOAA/CIMSS Volcanic Cloud Monitoring site (below) showed various characteristics of the ash plume at 0415 UTC.

A plot of 00 UTC rawinsonde data from Medan (below) helped to explain the different ash height and ash transport characteristics — the higher-altitude portion of the ash plume was transported westward by easterly flow above the 500 hPa (5.9 km) level, while the lower-altitude portion moved eastward due to westerly winds below 500 hPa.

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GOES-16 (GOES-East) True Color Red-Green-Blue (RGB) images created using Geo2Grid (above) showed widespread smoke from biomass burning across parts of Brazil (south of the Amazon River) on 09 August 2020. Most of this smoke was created by extensive burning during the previous day and evening — but later in the animation, several new smoke plumes can be seen growing from new fire activity.

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) showed clusters of thunderstorms that developed along and just behind a cold front moving eastward across Minnesota on 08 August 2020. The northernmost hail-producing thunderstorm in Minnesota exhibited an Above-Anvil Cirrus Plume (reference | VISIT training); in addition, a decaying thunderstorm complex in southeastern North Dakota eventually revealed the cyclonic circulation associated with a Mesoscale Convective Vortex.

GOES-16 Visible images (above) and Infrared images (below) included time-matched SPC Storm Reports.

A toggle between time-matched NOAA-20 VIIRS Infrared Window (11.45 µm) and GOES-16 “Clean” Infrared Window (10.35 µm) images (below) demonstrated the northwestward parallax displacement of GOES-16 cloud-top features (note: the same color enhancement enhancement has been applied to both images). Due to the 375-meter spatial resolution of VIIRS imagery, it was able to sense overshooting top infrared brightness temperatures as cold as -77.8ºC (compared to -65.7ºC with GOES-16). The higher resolution VIIRS image also provided a clearer depiction of the cloud-top gravity waves and tendrils of transverse banding.

A GOES-16 Infrared image with parallax displacement vectors and magnitudes (in km) from this site is shown below. For a 50,000 foot cloud top over southern Minnesota, the parallax adjustment was to the southeast at a distance of 21 km (13 miles) — this corresponded well to what was seen in the NOAA-20/GOES-16 comparison above.

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A previous blog post (link) detailed how to access NOAA CLASS to create Gridded NUCAPS (NOAA-Unique Combined Atmospheric Processing System) imagery from those data.  (You can also view some gridded NUCAPS fields here;  click here to see the 850-mb field of Temperature from that site, it is very similar to the imagery above).   This post details how to use the CSPP QuickLooks software package to create imagery at different levels.  These QuickLook fields give good information quickly and at many different levels for Direct Broadcast data.

Download the Sounder QuickLook software for Linux from the CIMSS website here.  Documentation is also available at the download website.  The files to download are shown in this graphic. The package is self-contained and requires only unzipping and un-tarring.

After downloading, define the $CSPP_SOUNDER_QL_HOME variable as the directory where the package sits on your unix platform.  Then, set up the environment with the command:  source $CSPP_SOUNDER_QL_HOME/cspp_sounder_ql_env.sh.

This software package works on NUCAPS EDR (Environmental Data Records) files created at Direct Broadcast sites by CSPP (that are also available after some time from CLASS), and those files can be found at websites such as this one: ftp://ftp.ssec.wisc.edu/pub/eosdb/ — underneath this are directories for NOAA-20 (‘j01’) and Suomi-NPP (‘npp’). For example, NOAA-20 data from 7 August 2020 from the ~1747 UTC overpass is at ftp://ftp.ssec.wisc.edu/pub/eosdb/j01/crisfsr/2020_08_07_220_1747/ (This website is not preserved forever but will go away after about a week. The directory includes an edr subdirectory that contains the files needed; a typical filename looks like this:  NUCAPS-EDR_v2r0_j01_s202008071752319_e202008071753017_c202008071830250.nc; it is the EDR for NOAA-20 and it contains data on 7 August 2020 from 1752 through 1753 UTC. The directory will include up to about 18 of these EDRs (the number depends on how long the satellite is within view of the Direct Broadcast antenna at CIMSS).

How do you create the QuickLooks?

1. Move the EDR files to your machine, and that’s easily done with wget ftp://ftp.ssec.wisc.edu/pub/eosdb/j01/crisfsr/2020_08_07_220_1747/edr/NUCAPS-EDR*.  Of course, the yyyy_mm_dd_jdy_hhmm value (2020_08_07_220_1747 above) changes with each satellite overpass!
2. Create a list of the files in that directory, i.e., files=$CSPP_SOUNDER_QL_HOME/data/NUCAPS-EDR*
3. Invoke the shell script from $CSPP_SOUNDER_QL_HOME/scripts/ql_level2_image.sh "$files" NUCAPS --dset temp --pressure 850.   This will create an image, shown above, that is a temperature mapping at the closest pressure level to 850 mb in the NUCAPS retrieval. (Pressure levels in the Radiative Transfer Model that is used by NUCAPS are listed here;  in the map label above, note that values are truncated, not rounded).  You can also map dewpoint temperature (dwpt), relative humidity (relh) and mixing ratio (wmix). By default, temperature scaling matches the bounds of the image, but you can specify the bounds if needed, using --plotMin=250.0 --plotMax=300.0, for example.  The time of the image is the time of the first scan line — for this ascending pass, it’s the southernmost line.  In this QuickLook image, the airmass difference between the relatively cool air over Ohio/Indiana and the warmer air to the south is apparent.

You can also create a QuickLook SkewT/logP plots for each scan. This produces one SkewT per ScanLine, at the mid-point along the scanline that contains 30 separate profiles.   The sounding below was produced by this command:

./ql_level2_skewt.sh ./data/NUCAPS-EDR_v2r0_j01_s202008071755119_e202008071755417_c202008071831450.nc NUCAPS

The SkewT has characteristics that suggest the presence of clouds.  What did this particular sounding look like in AWIPS?  That’s shown below.  In AWIPS, the sounding also terminated at about 550 mb, and the temperature and dewpoint lines above that level match the Quick Look sounding shown above.

NUCAPS Sounding Availability points from this NOAA-20 pass are shown below. The sounding point — in yellow — that is circled in blue is the one shown above. The sounding just to the east of that point — a green point that gives useful information down into the boundary layer — is shown here. Quick Looks choose the mid-point sounding along the line, and sometimes, as in this case, the retrieval that produced the profile did not converge.

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