Two PyroCbs in British Columbia

On 11 July there were a reported two pyroCbs in British Columbia. The first was at 56.4 N 123.9 W, producing a pyroCb around 00:30 UTC. GOES-15 detected the smoke plume and pyroCb cloud, as well as the fire hot spot. Starting at 22:30 UTC on 10 July, the animation below shows visible (.63 μm) on the left and shortwave IR (3.9 μm) on the right (click image to play animation). In the shortwave IR images the red pixels indicate very hot IR brightness temperatures exhibited by the fire source region.

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

GOES-15 0.63 μm visible (left) and 3.9 μm shortwave IR (right) images (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 22:30 UTC on 10 July, shows the brightness temperatures of this pyroCb. The pyroCb reached -47.2ºC (lime green color enhancement) around 00:30 UTC on 11 July. From the Prince George sounding this puts the cloud top at 10.5 km.

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

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

The second pyroCb occurred at 52.2 N 124 W around 05:00 UTC on 11 July. Since this pyroCb event happened during the evening hours visible imagery was not available. Again,  GOES-15 detected the smoke plume (using 10.7  μm imagery)  and pyroCb cloud, as well as the fire hot spot. Starting at 03:00 UTC on 11 July, the animation below shows IR imagery (10.7 μm) on the left and shortwave IR (3.9 μm) on the right (click image to play animation). In the shortwave IR images the red pixels indicate very hot IR brightness temperatures exhibited by the fire source region. Furthermore, in the 10.7 μm image the cloud-top brightness temperature was found to be -42.3 UTC around 05:00 UTC on 11 July. From the Kelowna sound this puts the cloud top height at 10.0 km.

GOES-15 10.7 μm visible (left) and 3.9 μm shortwave IR (right) images (click to play animation)

GOES-15 10.7 μm visible (left) and 3.9 μm shortwave IR (right) images (click to play animation)

OMPS AI index image (courtesy of Colin Seftor) on 11 July shows the transport of smoke. The data from 11 July shows high AI values in central Canada. By using HYSPILT backward trajectory plot (below; courtesy of Rene) the smoke from the AI index image is from the pyroCb in British Columbia.

OMPS Aerosol Index image on 11 July (click to enlarge)

OMPS Aerosol Index image on 11 July (click to enlarge)

Backward Trajectory using HYSPLIT on 11 June (click to enlarge)

Backward Trajectory using HYSPLIT on 11 June (click to enlarge)

To further investigate the transport of smoke from this fire CALIPSO was used. This LIDAR shows the height of the clouds from the wildfire. The first image below is the 532nm Total Attenuated Backscatter plot on 11 July from 10:12 UTC to 10:24 UTC. The smoke from this fire can be seen around 61 N  indicated by a light grey color. This plot shows that the smoke is moving northeast. The next image is the Depolarization image the smoke is indicated by a red/pink color. The third image is 1064 nm Total Attenuated Backscatter plot, the smoke on this plot is indicated by a light grey color. The fourth image is the Attenuated Ratio plot between 1064 nm and 532 nm. The smoke is indicated by the teal and purple pixels. The final image is the Vertical Feature Mask. This plot shows the different features that are in the atmosphere, the smoke is attributed as a cloud on this plot and is indicated by a light blue color.

CALIPSO 532 nm Total Attenuated Backscatter on 11 July (click to enlarge)

CALIPSO 532 nm Total Attenuated Backscatter on 11 July (click to enlarge)

CALIPSO Depolarization Ration on 11 July (click to enlarge)

CALIPSO Depolarization Ration on 11 July (click to enlarge)

CALIPSO 1064 nm Total Attenuated Backscatter on 11 July (click to enlarge)

CALIPSO 1064 nm Total Attenuated Backscatter on 11 July (click to enlarge)

CALIPSO Attenuated Color Ratio between 1064 nm and 532 nm on 11 July (click to enlarge image)

CALIPSO Attenuated Color Ratio between 1064 nm and 532 nm on 11 July (click to enlarge image)

CALIPSO Vertical Feature Mask on 11 July (click to enlarge image)

CALIPSO Vertical Feature Mask on 11 July (click to enlarge image)

Leave a Reply

Your email address will not be published.