By Scott Bachmeier •
2.5-minute rapid scan JMA Himawari-8 Shortwave Infrared (3.9 µm) images (above) showed numerous thermal anomaly (or “hot spot”, darker red to black pixels) signatures of wildfires across southeastern North Korea and northeastern South Korea on 04 April 2019 (media story). The fires were fanned by strong west-southwest winds in the wake of a cold frontal passage associated with an anomalously-deep midlatitude cyclone moving across far northeastern China (surface analyses); winds gusted to 53 knots at Yangyang International Airport (station identifier RKNY) to the south of Sokcho at 09 UTC (below). Standing wave clouds — forming in response to the strong westerly winds — were seen downwind of the mountainous terrain of the eastern Korean Peninsula from 1030-1930 UTC. Comparisons of VIIRS Day/Night Band (0.7 µm), Near-infrared (1.61 µm and 2.25 µm), Shortwave Infrared (3.75 µm and 4.05 µm) and Infrared Window (11.45 µm) images from NOAA-20 at 1649 UTC and Suomi NPP at 1739 UTC are shown below (courtesy of William Straka, CIMSS). A subtle thermal signature of the largest fires — located between Gangneug and Donghae, and also near Sokcho — was even apparent as darker pixels on the Infrared Window (I-Band 5, 11.45 µm) images. On the Day/Night Band images, note the striking lack of city lights in the southeastern portion of North Korea in these nighttime scenes. Thermal signatures of the fires were also captured by KMA COMS-1 Shortwave Infrared (3.9 µm) imagery (below), but not as well as with Himawari-8 given the inferior spatial resolution (4 km, vs 2 km for Himawari-8) and image frequency (15 minutes, vs 2.5 minutes with the Himawari-8 Japan Sector).Categories: COMS, Fire detection, Himawari-8, NOAA-20, Suomi NPP, VIIRS