GOES-17 (GOES-West) Low-level (7.3 µm), Mid-level (6.9 µm) and Upper-level (6.2 µm) Water Vapor images (above) revealed cold thermal signatures (brighter shades of white) associated with the highest-elevation portions of the Alaska Range on 05 December 2020. Note the slight northward shift (16-20 km, or 10-12 miles) in the apparent location of Denali in the GOES-17 images, due to parallax.

Plots of GOES-17 Water Vapor (ABI spectral band 8, 9 and 10) weighting functions calculated using 00 UTC rawinsonde data from Fairbanks (north of the Alaska Range) and from Anchorage (south of the Alaska Range) are shown below. Even with very large satellite viewing angles (or zenith angles) greater than 70 degrees — which would tend to shift the Water Vapor weighting function plots to higher altitudes —  the presence of very dry air within much of the middle to upper troposphere had the effect of bringing the weighting function peaks downward to pressure levels corresponding to those of the higher elevations of the Alaska Range.

The Total Precipitable Water (TPW) values seen on the 00 UTC Fairbanks and Anchorage soundings were 0.07 inch. However, a NOAA-20 NUCAPS sounding profile just 20-30 miles southwest of Denali around 12 UTC (below) yielded TPW values of only 0.01 inch. The green color of that sounding point indicated successful retrievals from both the Cross-track Infrared Sounder (CrIS) and Advanced Technology Microwave Sounder (ATMS) instruments.

Another NOAA-20 NUCAPS green sounding profile just southwest of Denali around 22 UTC (below) also yielded a TPW value of only 0.01 inch.

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As discussed on the Satellite Liaison Blog, wildfires driven by strong Santa Ana winds developed after sunset on 02 December — and 1-minute Mesoscale Domain Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above) displayed the thermal anomalies and smoke plumes associated with larger fires that persisted into the subsequent daytime hours on 03 December 2020.

GOES-17 True Color Red-Green-Blue (RGB) images created using Geo2Grid (below) showed the offshore transport of wildfire smoke during the day.

A before (24 November) / after (03 December) comparison of 30-meter resolution Landsat-8 False Color RGB images viewed using RealEarth (below) revealed the appearance of burn scars (darker shades of brown), active fire fronts (brighter shades of pink) and smoke plumes (shades of gray) associated with the Bond Fire east of Santa Ana and the smaller Airport Fire northwest of Corona.

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NOAA-20’s early afternoon pass over Lake Erie on 2 December 2020 produced a stunner of an image.  Snow surrounds the open lake, a result of the first widespread storm of the season over the eastern Great Lakes.

This image was created using Polar2Grid and Direct Broadcast data at the UW-Madison CIMSS.  The direct link is here.  Images from other passes from NOAA-20 are in this directory, and from Suomi-NPP are here.

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A very large iceberg broke off the Larsen-C Ice Shelf on the Antarctic Peninsula in July 2017 (recall this CIMSS Satellite Blog post, or this more recent post). While NOAA’s GOES-16 ABI visible sensors may not be ideal, they can monitor the iceberg’s location if the cloud cover is not too thick, as shown in the “natural color” animation. A similar loop, in the animated gif format. These composite images include information from ABI “blue” and “red” visible bands, along with the near-infrared “vegetation” band. A sample still image from November 21, 2020. More information can be found in the quick guide.

Since it was relatively cloud-free for several hours on 02 December, an animation of GOES-16 “Red” Visible (0.64 µm) images is shown below — note the presence of numerous small ice floes that had separated from the edges of A68a, and were circulating within the various ocean currents surrounding the large iceberg as it continued its slow drift toward South Georgia island. 

The geo2grid software was used to generate the images for these animations.

Thanks to a recent tweet by Simon Proud, showing a GOES-16 animation of A68a:

Happy that what started as a joke with @planetlabs
after a talk at @OxfordAOPP by CEO @Will4Planet has turned into beautiful pictures of Iceberg A68a!
Story by @BBCAmos here: https://t.co/n4j3EvIn11

Plus, a video of A68a over the past few days. pic.twitter.com/3cdnOQJSgV

— Simon Proud (@simon_sat) December 2, 2020

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