GOES-16: wildfires in southern California

July 8th, 2017 |

GOES-16 Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images, with hourly surface plots [click to play MP4 animation]

GOES-16 Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images, with hourly surface plots [click to play MP4 animation]

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

As southern California experienced a record-setting heatwave, 2 large wildfires were burning in San Luis Obispo and Santa Barbara counties on 08 July 2017: the Alamo Fire and the Whittier Fire. GOES-16 “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above) showed the smoke plumes and hot spots (red pixels) associated with these 2 fires.

The dense smoke plumes also exhibited a signature on the Near-Infrared “Cirrus” (1.37 µm) images (below), even though they were not composed of ice crystals (note that 10.3 µm Infrared Window brightness temperatures of the smoke plumes were warmer than -20º C, cyan color enhancement, the entire day). This example demonstrates that in a dry atmosphere, the “Cirrus” imagery will also be able to detect the presence of any airborne particles that are efficient scatterers of light (which includes smoke, dust and volcanic ash).

GOES-16 Visible (0.64 µm, left), Near-Infrared Cirrus (1.38 µm, center) and Infrared Window (10.3 µm, right) images, with station identifiers plotted in yellow [click to play MP4 animation]

GOES-16 Visible (0.64 µm, left), Near-Infrared Cirrus (1.37 µm, center) and Infrared Window (10.3 µm, right) images, with station identifiers plotted in yellow [click to play MP4 animation]

During  the nighttime prior to sunrise, with the benefit of ample illumination from a Full Moon, a long smoke plume streaming southwestward from the Alamo Fire was clearly seen on Suomi NPP VIIRS Day/Night Band (0.7 µm) imagery at 0910 UTC or 2:10 am local time (below). A very bright glow — larger than that of some nearby city lights — was co-located with the large hot spot on the corresponding Shortwave Infrared (3.74 µm) image.

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.74 µm) images [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.74 µm) images [click to enlarge]

GOES-16 Views a fire in Oakland, California

July 7th, 2017 |

GOES-16 Shortwave Infrared (3.9 µm) imagery, 1152-1357 UTC (Click to play animated gif)

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

The San Francisco Bay Area National Weather Service office Tweeted out an image (as noted by the Media) during the early morning of 7 July of the GOES-16 Fire Temperature, a GOES-16 Baseline Product (link) above a massive fire in Oakland (News Report). The animation above shows the evolution of the fire as detected by the 3.9 µm Brightness Temperature shown in AWIPS. The first indication of a fire appeared around 1200 UTC; the fire was difficult to discern after 1330 UTC.

GOES-16 Baseline Products include Fire-Detection products: Fire Temperature, Fire Power, and Fire Area. These products returned values from 1222 to 1247 UTC, when the fire was at its most intense. The table below shows the values as noted in AWIPS.  The fire peaked in terms of Power and Area at 1237 UTC.  The animation below is for Fire Temperature, and only one area is indicated (Fire Power and Fire Area caused the same region to show a non-zero values, the same values noted in the table below). GOES-16 Engineers and Scientists are investigating why the pixel size below does not match the correct pixel sizes above in the 3.9 µm imagery.

Time Fire Temperature (K) Fire Power Fire Area (Square Meters)
1222 UTC 892 K 86 4000
1227 UTC 873 K 92 4000
1232 UTC 849 K 153 4671
1237 UTC 833 K 167 5402
1242 UTC 889 K 137 4000
1247 UTC 1041 K 94 4000

 

GOES-16 Baseline Product Fire Temperature, 1217-1247 UTC on 7 July 2017 (Click to enlarge)

The fire was hot enough that it emitted detectable near-infrared 1.61 µm radiation, as shown below (animation). The brightest pixel, pointed to by the red arrow, over downtown Oakland in Alameda County (outlined in magenta) shows an albedo of 4.2% before sunrise!

GOES-16 Near-Infrared 1.61 µm image, 1237 UTC on 7 July 2017 (Click to enlarge)

Deadly Fire in Portugal

June 18th, 2017 |

Suomi NPP VIIRS Day/Night Band Visible Imagery (0.70 µm) at 0240 UTC on 18 June 2017 (Click to enlarge)

(Images in this blog post were created by William Straka, SSEC. Thanks William!!)

Parts of Pedrogao Grande in central Portugal (northeast of Lisbon) burned over the weekend in a massive forest fire. At least 62 people were killed (News Link; Youtube Video 1, 2). Suomi NPP overflew the region shortly after the fire started, and annotated VIIRS (Visible Infrared Imaging Radiometer Suite) Day/Night Band imagery is shown above (Click here for an image without annotation).  The size of the bright light signature from the fire (overlain with thin clouds) rivals that of Lisbon.

Suomi NPP VIIRS Shortwave Infrared imagery ( 3.75 µm) at 0240 UTC on 18 June 2017 (Click to enlarge)

Shortwave Infrared channels on Suomi NPP also testify to the intensity of the fire. The 3.75 µm above (Click here for an image with no labels) shows a saturated pixel (exceeding 367 K) over the hottest part of the fire.  The 1.61 µm channel in the near infrared also had a strong signal.   The 4.05 µm imagery (Click here for an image without annotation) shown below had a maximum brightness temperature exceeding 550 K! (This channel was specifically designed for fire detection).

Suomi NPP VIIRS Shortwave Infrared Imagery (4.05 µm) at 0240 UTC on 18 June 2017 (Click to enlarge)

Meteosat-10 Severi Infrared Imagery (3.9 µm) from 0000 to 0400 UTC on 18 June 2017 (click to enlarge)

The SEVERI Instrument on Meteosat-10 also detected this fire, and because Meteosat is geostationary, it provided better temporal coverage vs. the single snapshot from Suomi NPP. The animation above shows considerable cloud cover over Portugal, but very warm pixels are present starting after 0145 UTC. The toggle below compares 3.9 µm SEVIRI at 0245 UTC with 3.75 µm Suomi NPP VIIRS at 0240 UTC. The better spatial resolution of the VIIRS instrument is apparent, as are much warmer temperatures as expected given the smaller pixel size on VIIRS.  Note also a slight parallax shift.

Shortwave Infrared Imagery (3.9 µm from Meteosat-10 SEVIRI at 0245 UTC and 3.75 µm from Suomi NPP VIIRS at 0240 UTC) over Portugal (Click to enlarge)


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Suomi NPP VIIRS Day/Night Band visible (0.70 µm) imagery at 0145 UTC on 19 June 2017 (Click to enlarge)

Data from the 0145 UTC 19 June overpass on Suomi NPP show that the fire continues, although with less intensity. The Day/Night Band (above) and the 3.75 µm Shortwave Infrared (below) show the fire locations.

Suomi NPP VIIRS Shortwave Infrared (3.75 µm) imagery at 0145 UTC on 19 June 2017 (Click to enlarge)

 

GOES-16 daytime and nighttime images of the West Mims Fire in Georgia

April 25th, 2017 |

GOES-16 Blue Visible (0.47 µm, top), Red Visible (0.64 µm, center) and Shortwave Infrared (3.9 µm, bottom) images, with hourly surface plots in yellow [click to play animation]

GOES-16 “Blue” Visible (0.47 µm, top), “Red” Visible (0.64 µm, center) and Shortwave Infrared (3.9 µm, bottom) images, with hourly surface plots in yellow [click to play animation]

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

A daytime comparison of GOES-16 ABI “Blue” Visible (0.47 µm), “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above; also available as an MP4 animation) displayed the smoke plume and “hot spots” (black to yellow to red pixels) associated with the West Mims Fire that was burning in far southeastern Georgia on 25 April 2017 (this fire complex had been burning since 06 April, during which time the drought conditions had been worsening across that region). Downwind of the fire, in far northeastern Florida, smoke reduced the surface visibility to 2 miles at Jacksonville and 5 miles at Fernandina Beach.

During the subsequent nighttime hours — as the fires were beginning to decrease in both intensity and areal coverage — a comparison of “Snow/Ice” Near-Infrared (1.61 µm), “Cloud-Top Phase” Near-Infrared (2.24 µm) and Shortwave Infrared (3.9 µm) images (below; also available as an MP4 animation) showed that a bright glow from the most intense fires was evident in both of the Near-Infrared spectral bands.

GOES-16

GOES-16 “Snow/Ice” Near-Infrared (1.61 µm, top), “Cloud-Top Phase” Near-Infrared (2.24 µm, center) and Shortwave Infrared (3.9 µm, bottom) images, with hourly surface plots in yellow [click to play animation]

Although the spatial resolution of the 1.61 µm Band 5 is 1 km (at satellite sub-point) versus 2 km for the 2.24 µm Band 6, the bright nighttime fire signature was more defined on the 2.24 µm imagery; this is explained by examining a plot of the Spectral Response Function (SRF) for each band (below; courtesy of Mat Gunshor, CIMSS). For a very hot fire target — represented by the red 1200 K line — the 2.24 µm Band 6 SRF is located near the peak of the 1200 K curve, so more of the fire-emitted radiance can be sensed by Band 6 (in spite of its lower spatial resolution).

Spectral Response Function plots for GOES-16 ABI Band 5 (1.61 µm), Band 6 (2.24 µm) and Band 7 (3.9 µm) [click to enlarge]

Spectral Response Function plots for GOES-16 ABI Band 5 (1.61 µm), Band 6 (2.24 µm) and Band 7 (3.9 µm) [click to enlarge]