Mount Sinabung eruption in Indonesia

August 10th, 2020 |

Himawari-8 True Color RGB images [click to play animation | MP4]

Himawari-8 True Color RGB images [click to play animation | MP4]

JMA Himawari-8 True Color Red-Green-Blue (RGB) images created using Geo2Grid (above) displayed the gray to tan hues of a narrow west-to-east oriented volcanic ash cloud following an eruption of Mount Sinabung on 10 August 2020.

A sequence of Terra MODIS False Color RGB, Ash Probability, Ash Loading, Ash Height and Ash Effective Radius products from the NOAA/CIMSS Volcanic Cloud Monitoring site (below) showed various characteristics of the ash plume at 0415 UTC.

Terra MODIS False Color RGB, Ash Probability, Ash Loading, Ash Height and Ash Effective Radius [click to enlarge]

Terra MODIS False Color RGB, Ash Probability, Ash Loading, Ash Height and Ash Effective Radius [click to enlarge]

A plot of 00 UTC rawinsonde data from Medan (below) helped to explain the different ash height and ash transport characteristics — the higher-altitude portion of the ash plume was transported westward by easterly flow above the 500 hPa (5.9 km) level, while the lower-altitude portion moved eastward due to westerly winds below 500 hPa.

Plot of 00 UTC rawinsonde data from Medan, Indonesia [click to enlarge]

Plot of 00 UTC rawinsonde data from Medan, Indonesia [click to enlarge]

1 week of volcanic cloud emission from Nishioshima

August 1st, 2020 |

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

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 (faster animations are also available: gif | mp4). Brighter shades of pink in the Ash RGB images suggest a higher concentration of ash within the volcanic cloud. 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 Chichijima (below).

Plots of rawinsonde data from Chichijima [click to enlarge]

Plots of rawinsonde data from Chichijima [click to enlarge]

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

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


Vortices downwind of the Kuril Islands

July 28th, 2020 |

Himawari-8 “Red” Visible (0.64 µm) images [click to play animation | MP4]

Himawari-8 “Red” Visible (0.64 µm) images [click to play animation | MP4]

JMA Himawari-8 “Red” Visible (0.64 µm) images (above) showed trains of vortices extending downwind (southeast) of the Kuril Islands on 28-29 July 2020 (surface analyses). One unusual aspect of these features was the development of small cloud elements within the cloud-free “hole” portion of some of the vortices.

H/T to Santiago Gassó for alerting us to this interesting case.

Solstice solar eclipse shadow moving across southern Asia

June 21st, 2020 |

Himawari-8 True Color RGB images [click to play animation | MP4]

Himawari-8 True Color RGB images [click to play animation | MP4]

The shadow of a rare June Solstice annular solar eclipse moved across parts of Africa, the Arabian Peninsula and southern Asia on 21 June 2020. In Asia, the path of the shadow of totality was captured on Himawari-8 True Color Red-Green-Blue (RGB) images created using Geo2Grid (above).

The shadow was also evident in FY-2G Full Disk visible imagery, from the SSEC Geostationary Satellite Imagery site (below).

FY-2G Visible images [click to enlarge]

FY-2G Visible images [click to enlarge]