* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing *

GOES-16 “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above; a zoomed-in version is available here) displayed a subtle hazy signature of a smoke plume along with an intermittent “hot spot” (darker black pixels) associated with  a small fire — located near the center of the cyan circle — that was burning close to the southwest coast of Greenland on 01 August 2017. The approximate latitude/longitude coordinates of the fire were 67.87º N / 51.48º W, a location about halfway between Ilulissat (station identifier BGJN) and Kangerlussuaq (station identifier BGSF) and about halfway between the western edge of the Greenland Ice Sheet and the west coast .

Closer views using daily composites of 250-meter resolution Terra and Aqua MODIS true-color Red/Green/Blue (RGB) images (from 30 July to 04 August), sourced from RealEarth (below) indicated that the fire may have started close to 1540 UTC on 31 July — when a small white smoke and/or cloud feature (just north of the cursor) was seen at the fire source location on the Terra image (overpass time). The Aqua overpass time was around 1600 UTC.

Similar daily composite RGB images from Suomi NPP VIIRS (31 July to 04 August) are shown below. Note that the initial fire signature was not seen on the 31 May VIIRS image, due to the earlier overpass time  (1513 UTC) of the Suomi NPP satellite.

On 03 August, a 1507 UTC overpass of the Landsat-8 satellite provided a 30-meter resolution Operational Land Imager (OLI) false-color RGB image of the fire (below). This was the same day that a pilot took photos of the fire, as reported on the Wildfire Today site.

A comparison of one “before” (27 July) and two “after” (03 and 05 August) Landsat-8 OLI false-color RGB images (below) showed differences in smoke plume transport as the wind direction changed.

It is possible that this “natural fire” is similar to the Smoking Hills type of spontaneous combustion that has been observed in the Canadian Arctic (thanks to Ray Hoff, retired UMBC Professor of Physics, for that tip).

Credit to Mark Ruminski (NOAA/NESDIS) for first bringing this interesting event to our attention.

===== 09 August Update =====

The animations of daily Terra and Aqua true-color RGB images (below) have been extended to 09 August and 08 August, respectively.

Suomi NPP VIIRS true-color RGB images from 04-09 August (below) include VIIRS-detected fire locations plotted in red. The 09 August image showed that smoke from the fire had drifted west-southwestward over the adjacent offshore waters of Davis Strait.

===== 12 August Update =====

Another overpass of Landsat-8 on 12 August provided a glimpse of the fire burn scar, which appeared as a darker hue of reddish-brown. Note that the fire had burned eastward to the coast, during a day when stronger westerly winds prevailed.

Related sites:

NASA Earth Observatory

NPR

ESA Space in Images

AGU EOS

 

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* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing *

With a Severe Thunderstorm Watch in place, storms developed over far northeastern Colorado late in the day on 02 August 2017 which produced hail as large as 2.0 inches in diameter (SPC storm reports). Since GOES-14 (which had been placed into on-orbit storage as a spare satellite) was briefly activated for testing and evaluation, it afforded the unusual opportunity to view these storms from 4 different GOES perspectives (above). The Visible images (0.63 µm for the 3 legacy GOES, and 0.64 µm for GOES-16) are displayed in the native projections for each satellite.

A closer look using a higher image zoom factor (below) helps to demonstrate the advantage of higher spatial resolution with the GOES-16 0.64 µm “Red” Visible band (0.5 km at satellite sub-point, vs 1.0 km for the 3 legacy GOES) — especially for clearly identifying features such as thunderstorm overshooting tops. Also note that the 3 legacy GOES visible images do not appear as bright as those from GOES-16; visible imagery from GOES degrades with time, and older GOES Imager instruments do not have on-board calibration to account for this. However, the GOES-16 ABI instrument does have on-board visible detector calibration, so dimming of visible imagery over time should not be as noticeable.

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GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing

Tropical Storm Emily has formed in the eastern Gulf of Mexico on 31 July 2017, just to the west of Tampa/St. Petersburg, Florida. Its presence is possibly related to the surface front that has sagged south into Florida over the weekend.  (Sea Surface Temperatures in the area are very warm as well.) In the Visible (0.64 µm) animation above (a slower animation is available here), the curved bands of the low-level cloud field are noticeable just northwest of the large convective cluster near Tampa Bay.  Clean Window (10.3 µm) Infrared Imagery shows that offshore convection waned between 1100 and 1300 UTC, shifting to a location just south of Tampa.  (Click here for a slower animation)

About an hour after Emily made landfall, a toggle between Terra MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images, below, showed the compact cluster of deep convection — cloud-top infrared brightness temperatures were as cold as -74º C just off the Florida coast.

For more information on Emily, refer to the National Hurricane Center website, or to the CIMSS Tropical Weather Pages.

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* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing *

Can you find the plane near Des Moines? #contrail #GOES16 pic.twitter.com/H6kQQzrlc6

— NWS Des Moines (@NWSDesMoines) July 28, 2017

An aircraft “dissipation trail” formed over far southern Iowa during the late morning hours on 28 July 2017 — which was seen on GOES-16 “Red” Visible (0.64 µm), Near-Infrared “Snow/Ice” (1.61  µm) and Shortwave Infrared (3.9) µm) imagery (below).

As explained in this blog post, these types of cloud features are caused by aircraft either ascending or descending through a cloud layer composed of supercooled water droplets. Cooling from wake turbulence (reference) — and/or the particles from the jet engine exhaust acting as ice condensation nuclei — then cause the small supercooled water droplets to change phase and transform into larger ice crystals (which often fall from the cloud layer, creating “fall streak holes“).

Therefore, the glaciated aircraft dissipation trail appears darker on the 1.61 µm “snow/ice” images (since ice is a strong absorber of radiation at that wavelength), and colder (brighter white) on the 3.9 µm shortwave infrared images.

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