CIMSS Satellite Blog

Himawari-8 Ash RGB images, from 25 July to 01 August 2020 [click to play animation | MP4]

JMA Himawari-8 Ash Red-Green-Blue (RGB) images created using Geo2Grid (above) displayed the nearly continuous volcanic cloud emanating from Nishinoshima during the 1-week 25 July to 01 August period. The direction of plume transport switched from northwesterly/westerly to southerly/southeasterly during this time, which is explained by the transition in wind direction within much of the troposphere as revealed by rawinsonde data from nearby Chicijima (below).

Plots of rawinsonde data from Chichijima [click to enlarge]

VIIRS True Color RGB images from NOAA-20 and Suomi NPP [click to enlarge]

After the transition to southerly transport, VIIRS True Color RGB images from NOAA-20 and Suomi NPP as visualized using RealEarth (above), the surface visibility at Iwo Jima RJAW dropped to 4 miles on 01 August (below) as the hazy volcanic plume drifted across the area.

Time series plot of surface observation data from Iwo Jima [click to enlarge]

from CIMSS Satellite Blog https://cimss.ssec.wisc.edu/satellite-blog/archives/37820