Eruption of Popocatépetl in Mexico

October 2nd, 2019 |

GOES-16

GOES-16 “Red” Visible (0.64 µm), Split Window (10.3 – 12.3 µm), Ash RGB, Dust RGB and SO2 RGB images [click to play animation | MP4]

A sequence of GOES-16 (GOES-East) “Red” Visible (0.64 µm), Split Window (10.3 – 12.3 µm), Ash RGB, Dust RGB and SO2 RGB images (above) revealed signatures of volcanic plumes from an eruption of Popocatépetl on 02 October 2019. According to the Volcanic Ash Advisory issued at 1323 UTC (below), the longer plume moving westward — which was clearly seen in the Visible imagery — extended to an altitude of 21,000 feet. The second volcanic plume moving northwestward — which exhibited subtle signatures in the Split Window and RGB images — extended to an altitude of 24,000 feet. Although neither the Split Window nor the RGB images showed strong volcanic cloud signatures, taken together they helped to confirm the presence and transport of the 2 separate plumes.

GOES-16 Split Window image with the text of the 1323 UTC Volcanic Ash Advisory [click to enlarge]

GOES-16 Split Window (10.3 – 12.3 µm) image showing the text of the 1323 UTC Volcanic Ash Advisory [click to enlarge]

The radiometrically-retrieved Volcanic Ash Height product from the NOAA/CIMSS Volcanic Cloud Monitoring site indicated a maximum height in the 5-7 km range for the westward-moving plume (below).

GOES-16 Volcanic Ash Height product [click to play animation | MP4]

GOES-16 Volcanic Ash Height product [click to play animation | MP4]

Eruption of Ulawun in Papau, New Guinea

August 3rd, 2019 |

Volcanic ash height [click to play animation | MP4]

Volcanic ash height [click to play animation | MP4]

The Ulawun volcano erupted just after 09 UTC on 03 August 2019 — retrieved Volcanic Ash Height images from the NOAA/CIMSS Volcanic Cloud Monitoring site (above) showed values generally in the 16-18 km range, with some portions of the umbrella cloud as high as 18-20 km. An advisory issued by the Darwin VAAC estimated the maximum volcanic ash height to be 63,000 feet or 19.2 km.

Volcanic Ash Loading and Effective Radius products (below) indicated that there were high amounts of large ash particles within the volcanic cloud as it drifted southwestward.

Volcanic ash loading [click to play animation | MP4]

Volcanic ash loading [click to play animation | MP4]

Volcanic ash effective radius [click to play animation | MP4]

Volcanic ash effective radius [click to play animation | MP4]

Eruption of the Ubinas volcano in southern Peru

July 19th, 2019 |

GOES-16 Ash, SO2 and CIMSS Natural Color RGB images [click to play animation | MP4]

GOES-16 Ash, SO2 and CIMSS Natural Color RGB images [click to play animation | MP4]

A sequence of GOES-16 (GOES-East) Ash, SO2 and CIMSS Natural Color Red-Green-Blue (RGB) images (above) showed the volcanic cloud following an eruption of Ubinas in southern Peru on 19 July 2019. The volcanic plume was rich in both ash and SO2.

A plot of surface data from La Paz, Bolivia (below) indicated that the visibility dropped to 3 miles around 16 UTC as the volcanic cloud was drifting over that area (located about 150 miles downwind of Ubinas).

Time series of surface data from La Paz, Bolivia [click to enlarge]

Time series of surface data from La Paz, Bolivia [click to enlarge]

Terra MODIS Ash Probability, Ash Loading, Ash Height and Ash Effective Radius from the NOAA/CIMSS Volcanic Cloud Monitoring site (below) confirmed the high amounts of ash loading (of generally small ash particles) — with maximum radiometrically-retrieved Ash Height values in the 18-20 km range.

Terra MODIS Ash Probability, Ash Loading, Ash Height and Ash Effective Radius at 1440 UTC [click to enlarge]

Terra MODIS Ash Probability, Ash Loading, Ash Height and Ash Effective Radius at 1440 UTC [click to enlarge]

GOES-16 retrieved Ash Height values (below) were in general agreement with those obtained using the higher-resolution MODIS data.

GOES-16 Ash Height images [click to play animation | MP4]

GOES-16 Ash Height images [click to play animation | MP4]

Ulawun volcano erupts in Papau New Guinea

June 26th, 2019 |

Himawari-8 Visible (0.64 µm, left), Shortwave Infrared (3.9 µm, center) and Infrared Window (10.4 µm, right) images [click to play animation | MP4]

Himawari-8 Visible (0.64 µm, left), Shortwave Infrared (3.9 µm, center) and Infrared Window (10.4 µm, right) images [click to play animation | MP4]

The Ulawun volcano erupted just after 0430 UTC on 26 June 2019 — a comparison of Himawari-8 Visible (0.64 µm), Shortwave Infrared (3.9 µm) and Infrared Window (10.4 µm) images (above) showed the thermal anomaly (yellow to red 3.9 µm pixels) preceding the eruption and the development of a well-defined umbrella cloud after the eruption. The coldest cloud-top infrared brightness temperature was -83.6ºC in conjunction with a prominent overshooting top at 0600 UTC. Note the eastward-moving cloud material that originated from this overshooting top — judging from Merauke/Mopah, Indonesia rawinsonde data (plot | data), the westerly winds required for such transport existed in the stratosphere at altitudes of 20-24 km. The pocket of warmer cloud-top 10.4 µm brightness temperatures associated with this stratospheric cloud material was the warmest at (-57.2ºC) at 0640 UTC (which, with the adjacent -82.7ºC overshooting top, created a cold/warm couplet whose magnitude was 25.5ºC). In addition, concentric gravity waves propagating outward across the volcanic cloud top were evident on the imagery.

Himawari-8 Infrared Window images (below) showed that the volcanic cloud dissipated fairly quickly. The eastward drift of the stratospheric cloud material also became difficult to follow after a couple of hours — even in Low-level Water Vapor (7.3 µm) imagery (which is also sensitive to SO2 absorption).

Himawari-8 Infrared Window (10.4 µm) images [click to play animation | MP4]

Himawari-8 Infrared Window (10.4 µm) images [click to play animation | MP4]

Himawari-8 Shortwave Infrared (3.9 µm) images (below) revealed a thermal anomaly or “hot spot” (yellow to red pixels) for several hours leading up to the 0430 UTC volcanic eruption.

Himawari-8 Shortwave Infrared (3.9 um) images [click to play animation | MP4]

Himawari-8 Shortwave Infrared (3.9 µm) images [click to play animation | MP4]

Regarding the intensity of the thermal anomaly, a plot of volcano radiative power (VRP) and volcanic cloud longwave infrared brightness temperature (below) showed that the VRP exceeded 1 GW several hours prior to the formation of the eruption umbrella cloud.

Plot of volcano radiative power (red) and volcanic cloud longwave infrared brightness temperature (green), courtesy of Mike Pavolonis (NOAA/NESDIS) [click to enlarge]

Time series plot of volcano radiative power (red) and volcanic cloud longwave infrared brightness temperature (green), courtesy of Mike Pavolonis (NOAA/NESDIS) [click to enlarge]

Himawari-8 False Color RGB imagery along with radiometrically retrieved Ash Height, Ash Effective Radius and Ash Loading products (below) revealed a volcanic cloud characterized by high ash loading of large particles, having height values generally in the 16-20 km range (with a maximum height of 22 km).

False Color RGB (top left), Ash Height (top right), Ash Effective Radius (bottom left) and Ash Loading (bottom right) [click to play animation | MP4]

False Color RGB (top left), Ash Height (top right), Ash Effective Radius (bottom left) and Ash Loading (bottom right), courtesy of Mike Pavolonis (NOAA/NESDIS) [click to play animation | MP4]

An oblique view of of the Ulawun volcanic cloud was provided by GOES-17 “Red” Visible (0.64 µm) images (below). This view accentuated the vertical extent of overshooting tops, and the large solar angle helped to highlight the cloud-top gravity waves. The 3-dimensional aspect of the two distinct eruption pulses (with umbrella clouds at two different altitudes) along with the westward-drifting stratospheric plume were a bit more obvious in the GOES-17 images.

GOES-17 "Red" Visible <em>(0.64 µm)</em> images [click to play animation | MP4]

GOES-17 “Red” Visible (0.64 µm) images [click to play animation | MP4]