PyroCbs in Northwest Territories

On 11 July 2017 two pyroCbs formed in the Northwest Territories. GOES-15 detected the smoke plume and pyroCb cloud, as well as the fires hot spots. The first pyroCb cloud (~65.6º N, 129.9ºW) formed around 23:30 UTC on 10 July . The second formed shortly after around 67.1º N  128ºE. Starting at 23:00 UTC on 10 July, the animation below shows GOES-15 0.63 µm visible (left) and 3.9 µm shortwave IR (right) . In the shortwave IR images, the red pixels indicate very hot IR brightness temperatures exhibited by the fire source regions.

GOES-15 0.63 µm visible channel (left) and 3.9 µm shortwave IR channel images (right) (click to play animation)

GOES-15 0.63 µm visible channel (left) and 3.9 µm shortwave IR channel images (right) (click to play animation)

In addition, using GOES-15 10.7 μm IR channel the cloud-top IR brightness temperature could be found. The animation below, starting at 0:00 UTC on 11 July, shows the brightness temperature for the first pyroCb cloud reaching near  -43ºC at 4 UTC (green color enhancement). However, the second pyroCb does not reach the -40ºC. A better resolution satellite confirms that this is a pyroCb.

GOES-15 10.7 µm IR channel images (click to play animation)

GOES-15 10.7 µm IR channel images (click to play animation)

A 1-km resolution NOAA-19 AVHRR 10.8 µm Infrared Window image (below;courtesy ofRené Servranckx) revealed a minimum cloud-top IR brightness temperature of -58.1º C (red color enhancement) for the first pyroCb and -55.9º C for the second (red color enhancement) .

NOAA-19 AVHRR 0.64 µm visible (top left), 3.7 µm shortwave IR (top right), 10.8 µm IR window (bottom left) and false-color RGB composite image (bottom right)

NOAA-19 AVHRR 0.64 µm visible (top left), 3.7 µm shortwave IR (top right), 10.8 µm IR window (bottom left) and false-color RGB composite image (bottom right)

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