PyroCb in Alaska

On 18 June a pyroCb formed in Alaska. GOES-15 detected the smoke plume and pyroCb cloud, as well as the fire hot spot. The pyroCu (64.5 N 153.2W) occurred at around 1:30 UTC . Starting at 01:00 UTC on 18 June, 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 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 1:00 UTC on 18 June, shows the brightness temperature for the pyroCu was -49ºC at 3:10 UTC (green color enhancement).

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

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

The smoke was detected using CALIPSO lidar data (images courtesy of Mike Fromm). The images below show the products of lidar . The smoke can be seen ~65-72 N over Canada which is northeast of the pyroCb. The first image below is the 532nm Total Attenuated Backscatter plot on 19 June from 10:52 UTC to 11:15 UTC. The smoke from this fires is indicated by a gray color. The second image is 1064 nm Total Attenuated Backscatter plot, the smoke on this plot is indicated by a gray color. The third image is the Depolarization image the smoke is indicated by a red color. The fourth image is the Attenuated Ratio plot between 1064 nm and 532 nm. The smoke is indicated by purple pixels. The fifth 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 19 June

CALIPSO 532 nm Total Attenuated Backscatter on 19 June

CALIPSO 1064 nm Total Attenuated Backscatter on 19 June

CALIPSO 1064 nm Total Attenuated Backscatter on 19 June

CALIPSO Depolarization Ration on 19 June

CALIPSO Depolarization Ration on 19 June

CALIPSO Attenuated Color Ratio between 1064 nm and 532 nm on 19 June

CALIPSO Attenuated Color Ratio between 1064 nm and 532 nm on 19 June

CALIPSO Vertical Feature Mask on 19 June

CALIPSO Vertical Feature Mask on 19 June

In addition, a HYSPILT backward trajectory model was used to show where the smoke originated from that was detected by the CALIPSO imagery. The image below (courtesy of Mike Fromm) shows that the smoke from this pyroCb was detected by the CALIPSO imagery.

HYSPILT Backward Trajectory Model on 19 June at 11:00 UTC

HYSPILT Backward Trajectory Model on 19 June at 11:00 UTC

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