Pyrocumulonimbus clouds in Sichuan, China
10-minute JMA Himawari-9 AHI “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm) and “Clean” Infrared Window (10.4 µm) images (above) showed the formation of 2 pyrocumulonimbus (pyroCb) clouds spawned by a wildfire in Sichuan Province, China on 16 March 2024. The initial (smaller, shorter-lived) pyroCb developed at 0820 UTC — exhibiting cloud-top 10.4 µm infrared brightness temperatures of -40ºC and colder, denoted by the shades of blue — with the second (larger, somewhat longer-lived) pyroCb developing at 0910 UTC. The wildfire began to make a rapid northeastward run during the ~5 hour period shown in the animation. The fire environment across that region became more favorable as wind speeds increased with the approach of a deepening surface cyclone, as shown in surface analyses (the pyroCb-producing wildfire was located near 30º N latitude, 131º E longitude).Himawari-9 True Color RGB images created using Geo2Grid (below) showed the east-northeast transport of the wildfire smoke plume, with its embedded pyroCb cloud.