GOES-16 (GOES-East) Day Snow-Fog Red-Green-Blue (RGB), “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images (above) showed and undular bore propagating slowly north-northwestward across northeastern Minnesota and western Lake Superior on 11 December 2020. Also evident on the RGB and 1.61 µm images was the presence of a few industrial plumes — with their point sources being north of Hibbing — moving south-southwestward. These plume sources were likely large coal-fired power plants and other industrial sites located across that region; emissions from these industrial sources acted as cloud condensation nuclei, causing a higher concentration of smaller supercooled cloud droplets downwind of each plume source.

In a comparison of Suomi NPP VIIRS Visible (0.64 µm), Near-Infrared (1.61 µm) and Shortwave Infrared (3.74 µm) images at 1734 UTC (below), the industrial plumes appeared warmer (shades of green) due to enhanced reflection of incoming solar radiation by the smaller cloud droplets within the plumes.

Plots of rawinsonde data from International Falls, Minnesota (below) depicted a strong temperature inversion based around 1.2 km — the undular bore was likely ducted within this inversion.

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This blog has featured numerous blog posts that use visible imagery from two Geostationary Platforms (e.g., GOES-16/GOES-17 ; Himawari-8/GEOKOMPSAT-2).  Different cloud heights can be perceived in that imagery (for those who have mastered the art of crossing their eyes!).

GOES-R-type satellites also produce a Level 2 Product:  Cloud Top Height.  Can that product be used in concert with the Stereoscopic imagery to quantify the height differences seen in visible imagery?  The image above was created using Geo2Grid and ImageMagick: Geo2Grid to create the GOES-16 (left) and GOES-17 (right) visible imagery, ImageMagick to paste them together.  The GOES-R data (Full Disk in this case) have been remapped to a common projection. The scripts that does this sits below. (Click here to view Geo2Grid documentation).


../p2g_grid_helper.sh SWUSStereo -115.0 34.0 2000 -2000 960 720 > $GEO2GRID_HOME/SWStereo.conf
#
#
../geo2grid.sh -r abi_l1b -w geotiff -p C02 -g SWUSStereo --grid-configs $GEO2GRID_HOME/SWStereo.conf --method nearest -f /arcdata/goes_restricted/grb/goes17/2020/2020_12_11_346/abi/L1b/RadF/OR_ABI*G17_s2020346180*.nc
../geo2grid.sh -r abi_l1b -w geotiff -p C02 -g SWUSStereo --grid-configs $GEO2GRID_HOME/SWStereo.conf --method nearest -f /arcdata/goes_restricted/grb/goes16/2020/2020_12_11_346/abi/L1b/RadF/OR_ABI*G16_s2020346180*.nc
../add_coastlines.sh --add-borders --borders-resolution=h --borders-outline='black' --add-coastlines --coastlines-outline='blue' --coastlines-resolution=h --add-grid --grid-text-size 12 --grid-d 10.0 10.0 --grid-D 10.0 10.0 GOES-17_ABI_RadF_C02_20201211_180???_SWUSStereo.tif
../add_coastlines.sh --add-borders --borders-resolution=h --borders-outline='black' --add-coastlines --coastlines-outline='blue' --coastlines-resolution=h --add-grid --grid-text-size 12 --grid-d 10.0 10.0 --grid-D 10.0 10.0 GOES-16_ABI_RadF_C02_20201211_180???_SWUSStereo.tif
convert GOES-16_ABI_RadF_C02_20201211_180???_SWUSStereo.png GOES-17_ABI_RadF_C02_20201211_180???_SWUSStereo.png +append GOES-1617Stereo_ABI_RadF_C02_20201211_1800_SWUSStereo.png

Unfortunately, Geo2Grid doesn’t (yet!) display Level 2 products. But AWIPS does. A somewhat later Stereoscopic image (1941 UTC on 11 December) is shown below. GOES-R data (CONUS and PACUS in this case) are shown in a common projection, with GOES-16 shown on the left and GOES-17 shown on the right.

Can quantitative information from the Cloud Top Height Level 2 product, shown below, be easily incorporated into stereoscopic imagery?

First, I tried making side-by-side imagery with GOES-16 Visible and GOES-16 Cloud Top Heights. That is shown below.  Cross your eyes to combine the information.  Although one may be able to view something here — by aligning the state boundaries, your blogger did not find this side-by-side view useful — except in the conventional sense, seeing features in the visible to the left and corresponding information in the Level 2 product on the right.

Including the Cloud Top imagery to the right of the stereoscopic pair, however, did allow for a simple (although, perhaps, headache-inducing) comparison between the perceived height differences in the visible imagery and the quantitative differences in the Level 2 product.  If I had GOES-17 Cloud Heights, I would include those to the left of the visible pairs.

Perhaps the solution lies in color-enhancing the visible imagery based on the cloud top height.  That is work for the future.

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The Sandwich Product in AWIPS, a combination of visible imagery — proving texture — and infrared imagery providing color is one way to color the visible imagery based on cloud-top brightness temperatures (as a proxy for height).  A 2.5-hour animation of the Sandwich product is shown below. It does provide an interesting way to view heights of clouds!

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Space-X conducted a test flight of its Starship SN8 on 09 December 2020, which experienced a “Rapid Unscheduled Disassembly” upon landing — and 10-minute Full Disk sector GOES-17 (GOES-West) Visible, Near-Infrared and Shortwave Infrared images (above) displayed a bright visible signature and hot thermal signature of the landing site explosion (and also showed the eastward drift of the rocket booster condensation cloud produced during descent). GOES-17 was scanning the landing site at 22:52:38 UTC when it sampled these explosion signatures.

A combination of GOES-16 (GOES-East) 5-minute CONUS sector and 10-minute Full Disk sector image is shown below. Even though the satellite viewing angle or “zenith angle” was less for GOES-16 (39.22 degrees) than for GOES-17 (53.21 degrees), GOES-16 failed to capture signatures of the brief rocket landing explosion — in addition, the GOES-16 scanned the landing site nearly 1/2 minute earlier than GOES-17, at 22:52:12 UTC (CONUS sector) and 22:52:14 UTC (Full Disk sector). However, the eastward-moving rocket descent condensation cloud was still evident.

According to 00 UTC rawinsonde data from nearby Brownsville, Texas (below) a shift to westerly winds occurred at an altitude of 4200 meters (615 hPa) — indicating that the eastward-moving rocket booster condensation cloud existed within the middle troposphere.

Thanks to Todd Beltracci (The Aerospace Corporation) for the tip regarding optimal GOES-17 scan timing to capture the rocket explosion.

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A toggle between NOAA-20 VIIRS True Color and False Color Red-Green-Blue (RGB) images (above) showed a patch of snow cover that remained across parts of northwestern Oklahoma, the Oklahoma Panhandle and southwestern Kansas on 08 December 2020. This was residual snow cover from a winter storm that occurred 6 days earlier (on 02 December — NWS Amarillo | NWS Norman | NWS Dodge City | NOHRSC total snowfall).

The GOES-16 (GOES-East) Land Surface Temperature (LST) product at 1900 UTC (below) displayed LST values in the 30s F (shades of cyan to blue) over the patch of snow cover, in stark contrast to LST values in the 60s F (shades of green) across adjacent areas of bare ground.

GOES-16 Mid-level Water Vapor (6.9 µm) images (below) included plots of hourly surface weather type as the middle-tropospheric low responsible for the winter storm moved slowly across the region on 02-03 December.

===== 09 December Update =====

In spite of afternoon temperatures rising into the 50s and 60s F over surrounding bare-ground areas, a 08 December vs 09 December comparison of NOAA-20 VIIRS True Color RGB images (above) showed that the core of the residual snow cover remained intact — especially over Oklahoma — with minimal melting between the 2 days.

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