Multiple PyroCbs in Russia

On 24 August there were two pyroCbs near Lake Baikal in Russia. The first pyroCb formed at 52.6 N 109.5 E around 7:00 UTC, and the second pyroCb formed at 53.2 N 109.7 E around 9:00 UTC. Himawari-8 detected the smoke plume and clouds around the fires, as well as the fire hot spots. Starting at 06:00 UTC on August 24, the animation below shows visible (.64 μm) on the left and shortwave IR (3.9 μm) on the right (click image to play animation). In the shortwave IR images the darker black to red pixels indicate very hot IR brightness temperatures exhibited by the fire source region.

Himawari-8 0.64 μm visible (left) and 3.9 μm shortwave IR (right) images (click to play animation)

Himawari-8 0.64 μm visible (left) and 3.9 μm shortwave IR (right) images (click to play animation)

The third pyroCb formed around 52.8 N 108.5 E. Himawari-8 detected the smoke plume and clouds around the fires, as well as the fire hot spots. Starting at 08:00 UTC on August 24, the animation below shows visible (.64 μm) on the left and shortwave IR (3.9 μm) on the right (click image to play animation). In the shortwave IR images the darker black to red pixels indicate very hot IR brightness temperatures exhibited by the fire source region.

Himawari-8 0.64 μm visible (left) and 3.9 μm shortwave IR (right) images (click to play animation)

Himawari-8 0.64 μm visible (left) and 3.9 μm shortwave IR (right) images (click to play animation)

Himawari-8 10.4 μm IR channel imagery the minimum cloud-top IR brightness temperatures could be found. The animation below, starting at 06:00 UTC on 24 August, shows that the first pyroCb reached around -52.8 ºC (yellow color enhancement) at 07:30 UTC, the second pyroCb reaching -48ºC (lime green color enhancement) at 11:00 UTC, and the third pyroCb reach -48ºC (lime green color enhancement) at 11:00 UTC.

Himawari-8 10.4 μm IR images (click to play animation)

Himawari-8 10.4 μm IR images (click to play animation)

The fourth and fifth pyroCb happened later in the day so visible imagery wasn’t available. The fourth pyroCb formed at 53.4 N 109.8 E and the fifth forming at 54.2 N 109.6 E. Himawari-8 detected the smoke plume and clouds around the fires, as well as the fire hot spots. Starting at 11:00 UTC on August 24, the animation below shows shortwave IR (3.9 μm, click image to play animation). In the shortwave IR images the darker black to red pixels indicate very hot IR brightness temperatures exhibited by the fire source region.

Himawari-8 0.64 μm visible (left) and 3.9 μm shortwave IR (right) images (click to play animation)

Himawari-8 0.64 μm visible (left) and 3.9 μm shortwave IR (right) images (click to play animation)

Also, Himawari-8 10.4 μm IR channel imagery the minimum cloud-top IR brightness temperatures could be found. The animation below, starting at 11:00 UTC on 24 August, shows that the fourth pyroCb reached around -52.1 ºC (yellow color enhancement) at 13:00 UTC, and the fifth pyroCb reaching -48.7ºC (lime green color enhancement) at 14:30 UTC.

Himawari-8 10.4 μm IR images (click to play animation)

Himawari-8 10.4 μm IR images (click to play animation)

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 24 August from 05:15 UTC to 05:37 UTC, which is just a few hours before the pyroCbs formed. The smoke from these fires can be seen around 55 N  indicated by a dark grey and red color.  The second image is 1064 nm Total Attenuated Backscatter plot, the smoke on this plot is indicated by a red color. The third image is the Depolarization image the smoke is indicated by a blue/green color. The fourth image is the Attenuated Ratio plot between 1064 nm and 532 nm. The smoke is indicated by the magenta 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. The last image shows the subtype of the aerosols that have been detected by the LIDAR. This shows that the aerosols that the LIDAR has detected are smoke (indicated by the black pixels) around 55 N.

CALIPSO 532 nm Total Attenuated Backscatter on 24 August (click to enlarge)

CALIPSO 532 nm Total Attenuated Backscatter on 24 August (click to enlarge)

CALIPSO 1064 nm Total Attenuated Backscatter on 24 August (click to enlarge)

CALIPSO 1064 nm Total Attenuated Backscatter on 24 August (click to enlarge)

CALIPSO Depolarization Ration on 24 August (click to enlarge)

CALIPSO Depolarization Ration on 24 August (click to enlarge)

CALIPSO Attenuated Color Ratio between 1064 nm and 532 nm on 24 August (click to enlarge image)

CALIPSO Attenuated Color Ratio between 1064 nm and 532 nm on 24 August (click to enlarge image)

CALIPSO Vertical Feature Mask on 24 August (click to enlarge image)

CALIPSO Vertical Feature Mask on 24 August (click to enlarge image)

CALIPSO Aerosol Subtype plot on 08 August (click to enlarge image)

CALIPSO Aerosol Subtype plot on 08 August (click to enlarge image)

Below is an animation of the convergence at 250 mb shown by a color fill, the the 250 mb geopotential height contoured every 30 meters and the wind barbs.It has been investigated that upper level divergence is associated with the ability for pyroCu to turn into a pyroCb (Peterson et al., BAMS, Feb. 2015, 229-247). Starting at 6 UTC on 23 August the spots of the pyroCbs are indicated by the white dots. These pyroCbs are in an area of divergence indicated by the light blue and dark green color. This is conducive to the strengthening of the pyroCb. If there is divergence at upper levels there is rising air below that area of divergence. These conditions are favorable to the pyroCb developing.


250 mb Convergence(color fill), Geopotential Height (contoured every 30 m) and wind barbs every 6 hours starting on 23 August 6 UTC.


250 mb Convergence(color fill), Geopotential Height (contoured every 30 m) and wind barbs every 6 hours starting on 23 August 6 UTC.

This Skew-T taken at 12 UTC on 24 August after the pyroCb located at 52.6 N 109.5 E. From the Skew-T it is apparent that there is a good amount of CAPE which is favorable for convective development. This will help turn pyroconvection into a pyroCb. Furthermore, from the Skew-T the winds are veering indicating a cyclonic motion.
824skewt526Skew-T at 12 UTC (click to enlarge) Green line is dew point and red line is temperature.

This Skew-T taken at 12 UTC on 24 August after the pyroCb located at 52.8 N 108.5 E. From the Skew-T it is apparent that there is a good amount of CAPE which is favorable for convective development. This will help turn pyroconvection into a pyroCb. Furthermore, from the Skew-T the winds are veering indicating a cyclonic motion.
824skewt528Skew-T at 12 UTC (click to enlarge) Green line is dew point and red line is temperature.

This Skew-T taken at 12 UTC on 24 August after the pyroCb located at 53.2 N 109.7 E. From the Skew-T it is apparent that there is a small amount of CAPE which is favorable for convective development. The less amount of CAPE has lead to a warmer cloud top brightness temperature and a lower cloud top height. This will help turn pyroconvection into a pyroCb. Furthermore, from the Skew-T the winds are veering indicating a cyclonic motion.
824skewt532Skew-T at 12 UTC (click to enlarge) Green line is dew point and red line is temperature.

This Skew-T taken at 12 UTC on 24 August after the pyroCb located at 53.4 N 109.8 E. From the Skew-T it is apparent that there is a good amount of CAPE which is favorable for convective development. This will help turn pyroconvection into a pyroCb. Furthermore, from the Skew-T the winds are veering indicating a cyclonic motion.
824skewt534.002Skew-T at 12 UTC (click to enlarge) Green line is dew point and red line is temperature.

This Skew-T taken at 12 UTC on 24 August after the pyroCb located at 54.2 N 109.6 E. From the Skew-T it is apparent that there is a good amount of CAPE which is favorable for convective development. There is a dry layer around 550 hPa.This will help turn pyroconvection into a pyroCb. Furthermore, from the Skew-T the winds are veering indicating a cyclonic motion.
824skewt542Skew-T at 12 UTC (click to enlarge) Green line is dew point and red line is temperature.

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