GOES-17 (GOES-West) Shortwave Infrared (3.9 µm) and “Clean” Infrared Window (10.35 µm) images (above) displayed the thermal anomaly (cluster of hot pixels) and brief volcanic cloud resulting from an eruption of the Kilauea volcano on the Big Island of Hawai’i on 21 December 2020. The coldest cloud-top 10.35 µm infrared brightness temperature was -34.6ºC at 0840 UTC — which roughly corresponded to the 300 hPa or 9.6 km altitude according to 12 UTC rawinsonde data from nearby Hilo (plot | text). However, this volcanic cloud quickly dissipated in the very dry air aloft.

GOES-17 Near-infrared (1.61 µm and 2.24 µm) and Shortwave Infrared images (below) showed the variation in thermal signatures during the hours leading up to sunrise. The signature in Near-Infrared imagery was occasionally attenuated by the passage of trade wind cumulus clouds over the eruption site.

A comparison of Suomi NPP VIIRS Near-infrared (1.61 µm and 2.25 µm), Shortwave Infrared (3.75 µm) and Day/Night Band (0.7 µm) images (below) provided a high spatial resolution view of the thermal and emitted light signatures of the ongoing eruption at 1221 UTC.

A larger-scale view of GOES-17 Shortwave Infrared, SO2 RGB and Ash RGB images (below) showed the southward transport of a mid/high-altitude plume of SO2 (lighter shades of yellow to cyan) from the initial eruption, followed by the southwestward transport of a more persistent low-altitude plume of SO2 as the eruption continued during the day. No signature of volcanic ash was indicated (either qualitatively on the Ash RGB images, or on retrieved ash products from this site). At times the thermal anomaly of the eruption site exhibited 3.9 µm infrared brightness temperatures as hot as 105ºC.

GOES-17 True Color RGB images created using Geo2Grid (below) displayed the volcanic fog (or “vog”) plume that moved southwestward during the day — a portion of which became entrained into the circulation of a lee-side cyclonic gyre southwest of the Big Island.

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By animating daily NOAA GOES-16 ABI Full Disk visible imagery, how the Earth is illuminated over time can be seen. For example, the minimum in incoming solar radiation in the Northern Hemisphere associated with the Winter Solstice. For details, see “What is a Solstice?” by SciJinks. Or this NOAA https://www.noaa.gov/education/news/share-your-solstice-sunset-with-noaa-education post.

A Full Disk visible (band 2) loop at 11 UTC, (9 and 18 sec long versions).

Interactive web pages

An interactive web page with a years worth of GOES ABI Full Disk visible images at 11 UTC. The beginning date is the (northern hemisphere) winter solstice is 2019 and the end date is the winter solstice in 2020. A user can play the animation, as well as annotate the images. For example, draw lines along the terminator for different times of the year. One example might be to compare a solstice to an equinox. H/T Tom Whittaker, SSEC, for the webapp.

 

The Year in Review

A year-long Midwest CIMSS (Natural) true color (during the day) and the nighttime cloud microphysics) animation from GOES-16 at 18 UTC. Since this are daytime images, only the true color is being seen. A similar loop as above, but with a duration of 37 sec or 74 sec.

Year-long, GOES-16 loops at 18 UTC have been generated for other regions, including: the Northeast, Mid-Atlantic, Southeast, Texas and part of the Gulf of Mexico, Central US, Southwest, and Northwest. Similar loops from GOES-17 have been generated using images from 21 UTC for both Alaska and Hawaii. Note for the loop over parts of Alaska, the nighttime imagery is evident. These loops begin on the Winter Solstice 2019.

Year-long Hourly Loop over the Midwest

A very large (800 MB) file, showing a year-long (hourly) GOES-16 file over the Midwest (duration of 14 min). The loop is also on YouTube. Many features can be seen, including clouds, smoke and snow. This loop begin on the Winter Solstice 2019.

These images were made with either McIDAS-X or geo2grid, both from UW-Madison, SSEC.

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Suomi NPP VIIRS Infrared Window (11.45 µm) images (above) showed widespread ice leads in the Beaufort Sea during the 18 December – 20 December 2020 period. Some existing leads increased in width and/or length as they migrated westward, while some new leads were seen to form as land-fast ice fractured off the coasts of Alaska and larger islands of the Canadian Arctic Archipelago.

Suomi NPP VIIRS Infrared images with plots of NAM12 model surface winds on 20 December (below) indicated that the ice lead motion was influenced by surface wind stress — which also played a role in the clockwise flow of the Beaufort Gyre (the primary influence of ice lead motion in that part of the Arctic Ocean).

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CIMSS Scientists are working on a Machine-learning Ice Lead detection method, as described here.  The toggle below compares the MODIS and VIIRS computations of Ice Leads on 18 December 2020. Leads in this toggle are white; greys are suspected leads, but the detection algorithm ultimately could not confirm their presence. At present, the algorithm is challenged when leads are moving, as in this example. Note that Banks Island, on the right edge of the animation above, is in the lower left corner in the toggle below.

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A storm dropped historic snow amounts over parts of northern Pennsylvania, upstate New York and New England on 16-17 December 2020 (Places around Binghamton NY, for example, received more than 40″ of snow as shown in this map from this site.  Click here to see the Binghamton Radar loop during the storm).  The VIIRS True-Color image from ~1800 UTC on 17 December, above (created at the Direct Broadcast site at CIMSS, and available via LDM feed to NWS Forecast offices), shows the storm south of Cape Cod, and snow on the ground in the Mid-Atlantic states (the Great Valley in Virginia, Maryland and Pennsylvania is particularly apparent)

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