Fires in eastern Kansas and Oklahoma

April 11th, 2017 |

GOES-16 (left) and GOES-13 (right) Shortwave Infrared (3.9 µm) images [click to play animation]

GOES-16 (left) and GOES-13 (right) Shortwave Infrared (3.9 µm) images [click to play animation]

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

A comparison of GOES-16 and GOES-13 Shortwave Infrared (3.9 µm) images (above) showed numerous fire “hot spot” signatures (black to yellow to red pixels, with red being the hottest) from prescribed burning across the Flint Hills region of eastern Kansas and northeastern Oklahoma on 11 April 2017. Such fires are an annual tradition in this area, required to preserve the tallgrass prairies — for example, over 2.7 million acres were burned during Spring 2016. The 2-km spatial resolution (at satellite sub-point) and 5-minute scan interval of GOES-16 allowed for more accurate detection and monitoring of the fires (compared to the 4-km spatial resolution and 15-30 minute scan interval of GOES-13).

The corresponding Visible GOES-16 (0.64 µm) vs GOES-13 (0.63 µm) images (below) tracked the development and transport of smoke from the fires. Hourly reports of surface visibility (in statute miles) are plotted in red; at Fort Riley, Kansas, smoke reduced the visibility from 10.0 miles at 21 UTC to 1.0 mile at 23 UTC, adversely affecting air quality there.

GOES-16 Visible (0.64 µm, left) and GOES-13 Visible (0.63 µm, right) images, with hourly reports of surface visibility (statute miles, red) [click to play animation]

GOES-16 Visible (0.64 µm, left) and GOES-13 Visible (0.63 µm, right) images, with hourly reports of surface visibility (statute miles, red) [click to play animation]

Thermal signature of missile strikes at Shayrat Air Base in Syria

April 7th, 2017 |

EUMETSAT Meteosat-10 Shortwave Infrared (3.9 µm) images, with hourly surface reports; Shayrat Air Base is located at the center of the cyan circle [click to play animation]

EUMETSAT Meteosat-10 Shortwave Infrared (3.9 µm) images, with hourly surface reports; Shayrat Air Base is located at the center of the cyan circle [click to play animation]

EUMETSAT Meteosat-10 Shortwave Infrared (3.9 µm) images (above) showed the thermal signature or “hot spot” (darker black pixels) of fires resulting from US missile strikes at Syria’s Shayrat Air Base on 07 April 2017. The warmest infrared brightness temperature was 300.22 K on the 0030 UTC image (the SEVIRI instrument was scanning the Shayrat region at 00:40 UTC), which was about 25 K warmer than the surrounding background temperatures; though the fires were much smaller than the nominal 3 km spatial resolution of the 3.9 µm detector, the sub-pixel effect enables a signal of the fire radiative power to be registered.

A toggle between the 0015 and 0030 UTC images displayed using McIDAS-V (below; courtesy of William Straka, SSEC) highlights the appearance of the thermal signature at Shayrat Air Base. Two persistent hot spots located northeast of Palmyra could have been due to refinery or mining activities.

EUMETSAT Meteosat-10 Shortwave Infrared (3.9 µm) images at 0015 and 0030 UTC [click to enlarge]

EUMETSAT Meteosat-10 Shortwave Infrared (3.9 µm) images at 0015 and 0030 UTC [click to enlarge]

GOES-16 Mesoscale Sectors: improved monitoring of fire activity

March 19th, 2017 |

GOES-16 Shortwave Infrared (3.9 µm, left) and GOES-13 Shortwave Infrared (3.9 µm, right) images [click to play MP4 animation]

GOES-16 Shortwave Infrared (3.9 µm, left) and GOES-13 Shortwave Infrared (3.9 µm, right) images [click to play MP4 animation]

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

The ABI instrument on GOES-16 is able to scan 2 Mesoscale Sectors, each of which provides images at 1-minute intervals. For what was likely a prescribed burn in the Francis Marion National Forest (near the coast of South Carolina) on 19 March 2017, a comparison of 1 minute Mesoscale Sector GOES-16 and 15-30 minute Routine Scan GOES-13 Shortwave Infrared (3.9 µm) images (above; also available as a 50 Mbyte animated GIF) demonstrated the clear advantage of 1-minute imagery in terms of monitoring the short-term intensity fluctuations that are often exhibited by fire activity. In this case,  the intensity of the fire began to increase during 15:15-15:45 UTC — a time period when there was a 30-minute gap in routine scan imagery from GOES-13. The GOES-16 shortwave infrared brightness temperature then became very hot (red enhancement) beginning at 15:46:58 UTC, which again was not captured by GOES-13 — even on the 16:00 UTC and later images (however, this might be due to the more coarse 4-km spatial resolution of GOES-13, compared to the 2-km resolution of the shortwave infrared band on GOES-16). Similar short-term intensity fluctuations of a smaller fire (burning just to the southwest) were not adequately captured by GOES-13.

The corresponding GOES-16 vs GOES-13 Visible image comparison (below; also available as a 72 Mbyte animated GIF) also showed the advantage of 1-minute scans, along with the improved 0.5-km spatial resolution of the 0.64 µm spectral band on GOES-16 (which allowed brief pulses of pyrocumulus clouds to be seen developing over the fire source region).

GOES-16 Visible (0.64 µm, left) and GOES-13 Visible (0.63 µm, right) images [click to play MP4 animation]

GOES-16 Visible (0.64 µm, left) and GOES-13 Visible (0.63 µm, right) images [click to play MP4 animation]

 The rapid south-southeastward spread of the smoke plume could also be seen on true-color Red/Green/Blue (RGB) images from Terra/Aqua MODIS and Suomi NPP VIIRS, as viewed using RealEarth (below).

Terra MODIS, Aqua MODIS and Suomi NPP VIIRS true-color images [click to enlarge]

Terra MODIS, Aqua MODIS and Suomi NPP VIIRS true-color images [click to enlarge]

Multi-spectral views of smoke and fire with GOES-16 Data

March 10th, 2017 |

GOES-16 Infrared 3.9 µm images on 7 March 2017 [click to enlarge]

GOES-16 Infrared 3.9 µm images on 7 March 2017 [click to enlarge]

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

Tweets on Tuesday 7 March 2017 highlighted the fast-moving fires over the High Plains (that began burning on 6 March), and they also highlighted different bands available from the GOES-16 ABI. For example, this tweet references the loop above, showing an animation of 3.9 µm temperatures; that shortwave infrared channel is used because it is more sensitive to hot temperatures than longer wavelength infrared channels. The Norman WFO also tweeted out imagery, shown below, that included the 0.86 µm ‘Veggie’ band and the 0.47 µm visible band. Why use those two channels?

GOES-16 0.86 µm (near infrared) and 0.47 µm (visible) imagery from 07 March 2017 [click to enlarge]

GOES-16 0.86 µm (near infrared) and 0.47 µm (visible) imagery from 07 March 2017 [click to enlarge]

The 0.47 µm imagery is observing a part of the visible electromagnetic spectrum where scattering is largest, so smoke plumes are more apparent at that wavelength than at 0.64 µm. For a very obvious event such as this one, this might not be as important, but for a modest fire event over Florida, shown next, it can be. The 0.86 µm imagery is useful because it very distinctly shows fire burn scars; that is, the contrast at 0.86 µm between vegetated soil and adjacent burned regions is greater than occurs at other visible wavelengths. That is shown in the toggle below that steps through 0.47 µm, 0.64 µm, 0.86 µm, 1.61 µm and 3.9 µm imagery for one time on 7 March. The smoke plume is most distinct at the shortest wavelength 0.47 µm; it is very difficult to discern at 0.86 µm and especially at 1.61 µm because these near-infrared channels sense radiation at longer wavelengths that is unaffected by scattering of light by the small smoke particles. Note, however, that the small lakes do jump out at both wavelengths because of the very different reflectance properties of land and water at both 0.86 µm and 1.61 µm.

Finally, compare the 0.64 µm and 0.86 µm with special focus on the burn scars (here is a toggle between the two). Although the spatial resolution is greatest in the 0.64 µm visible imagery (0.5 km at the sub-satellite point, vs. 1 km at the sub-satellite point for the 0.86 µm imagery), the burn scars nevertheless are more distinct at 0.86 µm, in part because vegetated ground is more reflective at 0.86 µm than at 0.64 µm (See the figure in ‘Tim’s Topics’ on page 2 of the 0.86 µm fact sheet).

GOES-16 imagery from 2227 UTC on 07 March 2017. Wavelengths indicated in the image [click to animate]

GOES-16 imagery from 2227 UTC on 07 March 2017. Wavelengths indicated in the image [click to animate]


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A less extensive fire event occurred on 10 March 2017 in Florida. Focus on the largest hot spot (black pixels) in the 3.9 µm imagery in the center of the top third of the image below; this point is in southeastern Polk County. For this event, the smoke plume is more easily visualized in the 0.47 µm imagery than in the 0.64 µm or the 0.86 µm imagery. A burn scar does not appear in this case.

GOES-16 imagery from 1931 UTC on 10 March 2017. [click to animate]

GOES-16 imagery from 1931 UTC on 10 March 2017. [click to animate]

The GOES-R Website includes Fact Sheets for Band 1 (0.47 µm), Band 2 (0.64 µm), Band 3 (0.86 µm), Band 5 (1.61 µm) and Band 7 (3.9 µm).

AWIPS Note: The default enhancement (“IR_COLOR_CLOUDS_WINTER”) for 3.9 µm results in imagery that shows too little gradation over Florida during the daytime; for fire detection, either modify the colormap (this changed the temperature range from the default [-109 to 55] to -70 to 75, and is shown above) or switch to the”IR_COLOR_CLOUDS_SUMMER” enhancement.