Fatal wildfire in Valparaíso, Chile

April 13th, 2014
GOES-13 3.9 µm shortwave IR channel images

GOES-13 3.9 µm shortwave IR channel images

Strong winds helped a wildfire to spread very quickly through a portion of the city of Valparaíso, Chile — this fire forced large-scale evacuations, destroyed around 2000 homes, and was responsible for 12 fatalities. McIDAS images of 4-km resolution GOES-13 3.9 µm shortwave IR channel data (above) showed the fire “hot spot” (black to red color enhancement), which began late in the day on 12 April 2014, and burned through the night and into the day on 13 April. The hottest 3.9 µm IR brightness temperatures were 339.6 K (66.45º C) at 20:45 UTC and 340.8 K (67.65º C) at 23:45 UTC on 12 April.

Since the GOES-13 satellite only performs one full-disk scan (hence imaging the Southern Hemisphere) every 3 hours, the temporal behavior of this fire cannot be well ascertained. The ABI instrument on the future GOES-R satellite will perform a full-disk scan every 5 minutes.

Comparisons of 1-km resolution GOES-13 visible channel images and 4-km resolution GOES-13 3.9 µm shortwave IR images (below) showed that the narrow fire smoke plume spread rapidly to the northwest.

GOES-13 0.63 µm visible channel (left) and 3.9 µm shortwave channel images (right)

GOES-13 0.63 µm visible channel (left) and 3.9 µm shortwave channel images (right)

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Suomi NPP VIIRS 3.74 µm shortwave IR image

Suomi NPP VIIRS 3.74 µm shortwave IR image

A 375-meter resolution Suomi NPP VIIRS 3.74 µm (Band I4) shortwave IR image at 05:41 UTC (above) showed greater detail of the wildfire hot spot, which exhibited a maximum IR brightness temperature of 367.0 K (93.85º C). 367 K is actually the saturation temperature for the VIIRS Band I4 detectors, indicating that this was a very hot fire. Valparaiso is located about 112 km or 70 miles west-northwest of Santiago, Chile (station identifier SCEL).

By comparison, the 4-km resolution GOES-13 3.9 µm shortwave IR image close to that time (below) indicated that the maximum IR brightness temperature of the wildfire hot spot was only 316.5 K (43.35º C).

Suomi NPP VIIRS 3.74 µm shortwave IR channel image (left) and GOES-13 3.9 µm shortwave IR channel image (right)

Suomi NPP VIIRS 3.74 µm shortwave IR channel image (left) and GOES-13 3.9 µm shortwave IR channel image (right)

McIDAS-V images of VIIRS 3.9 µm (Band M15) shortwave IR and 0.7 µm Day/Night Band (DNB) data (below; courtesy of William Straka, CIMSS/SSEC) revealed that the large fire hot spot (yellow to red color enhancement on the shortwave IR image) was adjacent to and encroaching upon the bright night-time city lights of the Valparaiso area (as seen on the Day/Night Band image). In addition, ample illumination from a nearly-full Moon allowed the smoke plume to be seen on the DNB image, as it drifted northwestward over the adjacent waters of the Pacific Ocean.

Suomi NPP VIIRS 3.9 µm shortwave IR and 0.7 µm Day/Night Band images

Suomi NPP VIIRS 3.9 µm shortwave IR and 0.7 µm Day/Night Band images

Fires had been burning in parts of Chile since January 2014. Additional information on this Valparaíso fire can be found on the Wildfire Today site.

Grassland fires in Kansas

April 12th, 2014
GOES-13 3.9 µm shortwave IR images (click to play animation)

GOES-13 3.9 µm shortwave IR images (click to play animation)

Numerous grassland fires began to burn across parts of eastern Kansas (and also extreme northeastern Oklahoma) during the afternoon hours on 11 April 2014. AWIPS images of 4-km resolution GOES-13 3.9 µm shortwave IR channel data (above; click image to play animation) showed that many of these fires continued to burn into the overnight hours — the largest and most intense fire “hot spot” (black to yellow to red color enhancment) was seen northwest of Emporia, Kansas (station identifier KEMP) at 06:40 UTC or 1:40 AM local time, which exhibited an IR brightness temperature of 40º C. Smoke from these fires reduced the surface visibility as low as 2 miles at Manhattan (KMHK) and 4 miles at Topeka (KTOP). However, as high cirrus clouds began to move over the region later in the night and toward dawn, identification of the fire hot spots on GOES imagery became more difficult.

A comparison of 1-km resolution Suomi NPP VIIRS 3.74 µm and 4-km resolution GOES-13 3.9 µm shortwave IR images just after 07 UTC or 2 AM local time (below) demonstrated the advantage of higher spatial resolution for detecting not only the locations of many of the smaller fire hot spots, but also for providing a more accurate value of the intensity of the larger, hotter fires; in this case, the highest IR brightness temperature of the larger fire northwest of Emporia on the VIIRS image was 50.5º C (red color enhancement), compared to only 22.5º C (darker black color enhancement) on the GOES-13 image.

Suomi NPP VIIRS 3.74 µm and GOES-13 3.9 µm shortwave IR images

Suomi NPP VIIRS 3.74 µm and GOES-13 3.9 µm shortwave IR images

Since these fires were burning at night, they also exhibited bright signatures on the 0.7 µm Suomi NPP VIIRS Day/Night Band (DNB) image; lights from cities and towns also appeared as bright spots on the DNB image, but a comparison with the corresponding VIIRS 3.74 µm shortwave IR image helped to identify which could be attributed to actively burning fires (below).

Suomi NPP VIIRS 0.7 µm Day/Night Band and 3.74 µm shortwave IR images

Suomi NPP VIIRS 0.7 µm Day/Night Band and 3.74 µm shortwave IR images

As mentioned above, high cirrus clouds moving over the region later in the night made fire hot spot identification more difficult on the 4-km resolution GOES-13 shortwave IR imagery. However, a 1-km resolution POES AVHRR 3.74 µm shortwave IR image at 11:50 UTC or 6:50 AM local time (below) was able to detect a number of fire hot spots (darker black pixels) through the cirrus cloud features.

POES AVHRR 3.74 µm shortwave IR image

POES AVHRR 3.74 µm shortwave IR image

Widespread blowing dust across the south-central US

March 18th, 2014
GOES-13 0.63 µm visible channel images (click to play animation)

GOES-13 0.63 µm visible channel images (click to play animation)

McIDAS images of GOES-13 0.63 µm visible channel data (above; click image to play animation) showed two very large blowing dust features during the afternoon hours on 18 March 2014: one moving southward out of southeastern Colorado, and another moving eastward out of New Mexico across Texas and Oklahoma. Winds gusted to 75 mph in southeastern Colorado, and 60 mph in the Texas Panhandle; surface visibilities were reduced to near zero at times at some locations. As a result, some highways were closed in southeastern Colorado. Another significant blowing dust event had impacted much of this same region one week earlier.

GOES-13 0.63 µm visible channel images with METAR surface reports (click to play animation)

GOES-13 0.63 µm visible channel images with METAR surface reports (click to play animation)

Taking a closer look at the large southward-moving dust plume with AWIPS images of GOES-13 0.63 µm visible channel data (above; click image to play animation) and GOES-13 3.9 µm shortwave IR channel data (below; click image to play animation), it can be seen that a large wildfire began to burn around 19:15 UTC (2:15 PM local time) near the Texas/Oklahoma border as the strong winds associated with the leading edge of the dust storm moved through. The hot fire (yellow to red to black pixels on the shortwave IR images) produced pyrocumulus clouds and a smoke plume that rose above the top of the dust layer, high enough to cast a shadow due to the low sun angle at the end of the day. Note from the distance scale on the lower left portion of the visible images that this “wall of dust” was at least 300 miles wide.

GOES-13 3.9 µm shortwave IR images with METAR surface reports (click to play animation)

GOES-13 3.9 µm shortwave IR images with METAR surface reports (click to play animation)

The CLAVR-x POES AVHRR Cloud Top Height product (below) indicated that the top of the southward-moving dust layer was generally 1-2 km above ground level (cyan to light green color enhancement).

POES AVHRR Cloud Top Height product

POES AVHRR Cloud Top Height product

Terra and Aqua MODIS true-color Red/Green/Blue (RGB) images visualized using the SSEC RealEarth web map server (below) revealed that the composition of the dust from the 2 source regions took on a different appearance, indicating that the nature and composition of the aerosols were different.

Terra and Aqua MODIS true-color RGB images

Terra and Aqua MODIS true-color RGB images

AWIPS images of the Terra and Aqua MODIS “reverse absorption” 11-12 µm IR brightness temperature difference product (below) offered another method of identifying the areas where the airborne dust was the most dense.

Terra and Aqua MODIS 12.0-11.0 µm IR brightness temperature difference product

Terra and Aqua MODIS 12.0-11.0 µm IR brightness temperature difference product

Additional satellite images from this event can be found on the Wide World of SPoRT and RAMMB: GOES-R Proving Ground Blog sites.

===== 19 March Update =====

IDEA-I forecast aerosol trajectories (click to play animation)

IDEA-I forecast aerosol trajectories (click to play animation)

The IDEA-I MODIS Aerosol Optical Depth product indicated that much of the airborne dust remained over southern and eastern Texas on 19 March. Forecast forward trajectories (above; click image to play animation) suggested that some of this dust would get recirculated back northward across western Texas, and eventually move over Kansas in 24-48 hours.

Large bushfires in southeastern Australia

January 16th, 2014

MTSAT-2 0.68 µm visible channel (left) and 3.75 µm shortwave IR (right) images [click to play animation]

MTSAT-2 0.68 µm visible channel (left) and 3.75 µm shortwave IR (right) images [click to play animation]

An extended period of hot, dry weather led to the development of multiple large bushfires across parts of southeastern Australia, some of which began to produce pyrocumulonimbus (pyroCb) clouds during the 15-16 January 2014 period. McIDAS images of MTSAT-2 0.68 µm visible channel and 3.75 µm shortwave IR channel data (above; click image to play animation; also available as an MP4 animation) showed the development of a well-defined pyroCb associated with the Northern Grampions fire in the state of Victoria. After the visible images on the left panels faded to black during the night-time hours, the shortwave IR images on the right panels showed that many of the fire “hot spots” (denoted by the darker black pixels) continued to grow during the night.

MTSAT-2 10.8 µm longwave IR channel images (below; click image to play animation; also available as an MP4 animation) indicated that cloud-top IR brightness temperatures associated with the rapidly-growing pyroCb cloud became as cold as -38.7º C (lighter green color enhancement) at 07:32 UTC. Other areas of cold-topped thunderstorms developed near the coast, likely initiated by sea breeze and/or local terrain influences. Surface reports ploted on the IR images revealed very hot temperatures: for example, it was 109º F (42.8º C) at Melbourne Essondon (station identifier YMEN) at 04 UTC.

MTSAT-2 10.8 µm longwave IR images [click to play animation]

MTSAT-2 10.8 µm longwave IR images [click to play animation]

A larger-scale view of MTSAT-2 0.68 µm visible channel images (below, visualized using the SSEC RealEarth web map server) showed that there were some large bushfires to the northwest that were producing long, dense smoke plumes which were drifting southward off the coast.

MTSAT-2 0.68 µm visible channel images [click to play animation]

MTSAT-2 0.68 µm visible channel images [click to play animation]