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.

Grass fires in Kansas, Oklahoma and Texas

March 6th, 2017 |

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

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

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

Widespread grass fires began to burn across parts of southwestern Kansas, northwestern Oklahoma and the Texas Panhandle on 06 March 2017. The fires grew very quickly during the late morning and early afternoon hours, due to strong southwesterly winds (with gusts as high as 67 mph in Oklahoma)  behind a dryline (surface analyses); a cold front then moved southward across the region during the late afternoon and evening hours, bringing strong northerly/northwesterly winds. In a comparison shown above of Shortwave Infrared (3.9 µm) images — 1-minute interval (Mesoscale Sector) 2-km resolution GOES-16 vs. 5-7 minute interval (Rapid Scan Operations) 4-km resolution GOES-13 (also available as a 204 Mbyte animated GIF) — a large fire (the Starbuck Fire) can be seen making a fast northeastward run from Oklahoma into Kansas behind the dryline; then, after the passage of the cold front, the leading edge of that and another large fire turned southward and moved from Kansas back into Oklahoma. Another large fire in the Texas Panhandle (the Perryton Fire) moved rapidly eastward and crossed the border into Oklahoma. At least 7 deaths have resulted from these fires (CNN).

===== 07 March Update =====

The large size of the grass fire burn scars could be seen in comparisons of true-color and false-color Red/Green/Blue (RGB) images from Terra MODIS (1732 UTC), Suomi NPP VIRS (1857 UTC) and Aqua MODIS (1912 UTC) images viewed using RealEarth (below).

Terra MODIS true-color and false-color images [click to enlarge]

Terra MODIS true-color and false-color images [click to enlarge]

Suomi NPP VIIRS true-color and false-color images [click to enlarge]

Suomi NPP VIIRS true-color and false-color images [click to enlarge]

Aqua MODIS true-color and false-color images [click to enlarge]

Aqua MODIS true-color and false-color images [click to enlarge]

The creation of true-color and false-color images such as these will be possible using the ABI spectral bands available on GOES-16 and the GOES-R series of satellites. A separate blog post highlighting other multi-spectral GOES-16 views of these fire burn scars on 07 March  is available here.

GOES-16: fire detection in Florida

February 20th, 2017 |

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

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

Numerous small fires were burning in the Lake Okeechobee area of southern Florida on 20 February 2017. A comparison of GOES-16 ABI (at rapid scan 30 second intervals) and GOES-13 (at routine 15-30 minute intervals) 3.9 µm Shortwave Infrared images (above; also available as a 71 Mbyte animated GIF) showed the “hot spots” — dark black to yellow to red enhancement, with red being the hottest — associated with these fires. Since many of the fires were agricultural sugar cane burns (which tend to be brief, but intense), the vast majority were not detected using the routine operational 15-30 minute scan interval of GOES-13; only the 30-second interval rapid scan GOES-16 images were able to capture these short-lived events. GOES-16 (the first in the GOES-R series) will provide the capability of 30-second or 60-second images within special Mesoscale Sectors.

The improved spatial resolution of the GOES-16 data (2-km at satellite sub-point, vs 4-km for GOES-13) also aided in the detection and characterization of the small and short-lived fires.

Fire detection points from the NOAA Hazard Mapping System for 20 February are shown below.

NOAA Hazard Mapping System fire detection points [click to enlarge]

NOAA Hazard Mapping System fire detection points [click to enlarge]

Note: GOES-16 data shown on this page are preliminary, non-operational data and are undergoing on-orbit testing.