By Scott Bachmeier •
GOES-18 (GOES-West) Dust RGB images (above) showed a plume of resuspended volcanic ash (brighter shades of violet) from Mount Aniakchak, which was being lofted by strong SE winds — gusting as high as 45 knots at Port Heiden — and transported NW across Bristol Bay on 26 October 2023. A Volcanic Ash Advisory was issued at 2130 UTC (below), cautioning pilots of hazardous airborne ash between the Surface and an altitude of 3000 feet. While a subtle signature of the plume was also evident in GOES-18 Ash RGB imagery, it was a bit more obvious in the Dust RGB (below) — both RGBs use the same spectral bands and spectral band differences, but the individual RGB components are scaled differently (so an examination of both is advised, in order to determine which RGB is best to track this type of ash-related feature). GOES-18 True Color RGB images from the CSPP GeoSphere site (below) provided a good view of the resuspended ash plume (shades of tan) as it moved NW across the water.Categories: GOES-18, Red-Green-Blue (RGB) images