Fire detection « CIMSS Satellite Blog

Caughlin Wildfire near Reno, Nevada

November 18th, 2011

GOES-15 3.9 µm shortwave IR images (click image to play animation)

The 2000-acre “Caughlin Fire” started burning around 08:45 UTC (1:45 am local time) in the hilly terrain near Reno, Nevada, and soon grew out of control due to strong winds gusting as high as 74 mph. McIDAS images of GOES-15 3.9 µm shortwave IR data (above) showed the “hot spot” (black to yellow to red enhanced pixels) associated with the fire. At least 30 homes were destroyed, with many more damaged by the fire. Thousands of residents were evacuated.

Evidence of the strong winds across the region could be seen on an AWIPS image of MODIS 6.7 µm water vapor channel data (below), with a number of very pronounced mountain waves showing up on the image. These mountain waves persisted for several hours, and were responsible for pilot reports of severe turbulence, wind shear, and 50-knot crosswinds during descent to final approach into the Reno airport. The highest wind gust reported at the Reno airport was 44 mph, and surface visibility was also reduced to 6 miles at the airport due to smoke.

MODIS 6.7 µm water vapor channel image

Posted in Air quality, Aviation, Fire detection, GOES-15, MODIS | No Comments »

Blowing dust event in Texas and New Mexico

October 18th, 2011

GOES-11, GOES-15, and GOES-13 visible channel images (click image to play animation)

A major blowing dust event occurred in the wake of a strong cold frontal boundary that moved rapidly southward across western Texas and eastern New Mexico late in the day on 17 October 2011 — the blowing dust reduced surface visibilities to near zero in some locations as winds gusted as high as 75 mph (see NWS Lubbock story). McIDAS images of GOES-11 (GOES-West), GOES-15, and GOES-13 (GOES-East) visible channel data during the daylight hours and shortwave IR data after sunset (above; click image to play animation) showed the southward propagation of the well-defined arc of blowing dust (or “haboob”), along with the surge of cooler air behind the cold front. A few wildfire “hot spots” (darker black pixels) were also evident on the GOES shortwave IR images, a result of fires started by downed power lines.

Much of that region had been experiencing long-term extreme to exceptional drought conditions — and an AWIPS image of the MODIS Normalized Difference Vegetation Index (below) showed very low NDVI values across much of western Texas the day before the dust storm.

MODIS Normalized Difference Vegetation Index

Posted in Air quality, Fire detection, GOES-11, GOES-13, GOES-15, MODIS | No Comments »

Chemical plant fire near Dallas, Texas

October 3rd, 2011

GOES-11, GOES-15, and GOES-13 visible channel images

A McIDAS image comparison of GOES-11 (GOES-West) 0.65 µm visible channel, GOES-15 0.63 µm visible channel, and GOES-13 (GOES-East) 0.63 µm visible channel data (above) showed the dark smoke plume from a fire burning at a chemical plant in Waxahachie, Texas (about 30 miles south of Dallas) on 03 October 2011. (Note: GOES-15 is scheduled to replace GOES-11 as the operational GOES-West satellite in December 2011).

A similar comparison of the GOES-11, GOES-15, and GOES-13 3.9 µm shortwave IR channels (below) indicated that no obvious fire “hot spot” was evident before the appearance of the dark smoke plume — the brighter yellow colors highlight pixels which have an IR brightness temperature hotter than 45º C. This 45º C threshold was exceeded at 16:30 UTC on the GOES-15 and GOES-13 images, and at 16:45 on the GOES-11 images; on the visible channel imagery, the dark smoke plume was seen 30 minutes earlier at 16:00 UTC on all 3 satellites.

GOES-11, GOES-15, and GOES-13 shortwave IR images

A 17:32 UTC Terra MODIS Red/Green/Blue (RGB) true color image from the SSEC MODIS Today site (below, viewed using Google Earth) confirmed the very dark nature of the smoke plume from this particular fire, which was causing some evacuations (news media story).