After 124 years dormant, the Jebel Al-Tair volcano erupted throwing lava and ash hundreds of metres into the air.
More information and detailed analysis of the feature can be found in the In Depth section.
by HansPeter Roesli and Jochen Kerkmann (EUMETSAT)
Jebel Al-Tair is a stratovolcano in the southern part of the Red Sea and is located in the Republic of Yemen. Stratovolcanoes are tall conical volcanoes with a steep profile and periodic explosive eruptions. For more information on Jebel Al-Tair see Global Volcanism Program.
After 124 years dormant, the volcano erupted on 30 September 2007 throwing lava and ash hundreds of metres into the air. According to Meteosat-9 Ash RGB derived product imagery (see real-time products), the first major eruption occurred between 11:15 and 11:30 UTC.
The Ash RGB product is tuned to detect SO2 and ash clouds typical of volcanic eruptions. In fact, at 11:30 UTC (PNG, 302 KB) a tiny bright puff is visible in a colour identifying SO2 , whereas at 11:15 UTC (PNG, 268 KB) no signal is visible. Already at 11:45 UTC (PNG, 305 KB) the initial SO2 release is followed by a major volcanic cloud with mixed constituents (ice, SO2 , ash) that drifts away to the north-west (driven by the high-level winds).
As in the case of the Soufriere Hills eruption in May 2006, the SEVIRI data suggest that in the early phase of this major eruption the ice cloud masked the SO2 signature. This is either because the radiative effects of the ice particles prohibited detection of SO2 or because much of the SO2 gas was absorbed onto the ice particles, only to sublimate at a later stage as the ice evaporated.
In addition to the spectacular high-level volcanic (SO2 ) cloud, which travelled long distances around the world, in the hours following the major eruption Jebel Al-Tair continued to emit SO2 at low levels (see RGB product at 21:30 UTC (30 September), PNG, 355 KB).
On 1 October 2007, the high-level SO2 cloud can be followed up the western coast of the Red Sea (see RGB product at 05:00 UTC (1 October), PNG, 337 KB). On 2 October the high-level SO2 cloud splits into two separate clouds: the larger one takes a more easterly track, following the subtropical jet stream, and crosses the Red Sea; the smaller cloud moves slowly northward over Egypt (see Aura/OMI SO2 product (2 October), JPG, 153 KB, source: S. Carn).
Unfortunately, over desert surfaces the MSG Ash RGB product looses sensitivity and the gas cloud can no longer be followed over Egypt and Saudi Arabia (see Animation Met-9 Ash RGB, 30 Sep 11:15 UTC–1 Oct 21:30 UTC, MPG, 7 MB).
An AIRS product from the Aqua satellite (JPG, 220 KB, source: F. Prata) shows that by 2 October the SO2 cloud has arrived as far as the northern parts of the Arabian Gulf. The SO2 signal from the GOME-2 instrument on Metop-A (see animation, 30 Sep–7 Oct, animated GIF, 403 KB, courtesy: Andreas Richter, University of Bremen) clearly shows the long-range transport of the SO2 cloud by the subtropical jet stream (confirmed by the Aura/OMI SO2 products given under 'see also').
Satellite Images of Jebel Al-Tair Eruption
RGB Composite (Ash RGB)
IR12.0–IR10.8, IR10.8–IR8.7, IR10.8
Full Resolution (PNG, 319 KB)
Animation (11:00–20:00 UTC, MPG, 12 MB)
RGB Composite (Airmass RGB)
WV6.2–WV7.3, IR9.7–IR10.8, WV6.2
Full Resolution (PNG, 322 KB)
Animation (11:15–20:00 UTC, MPG, 11 MB)
Hysplit model forward trajectories (GIF, 38 KB, source: NOAA)
Animation Met-9 HRV Channel (11:15–13:15 UTC, MPG, 4 MB)
Animation Met-9 Ash RGB (30 Sep 11:15 UTC–1 Oct 05:00 UTC, MPG, 8 MB)
Animation Met-9 Ash RGB (30 Sep 11:15 UTC–1 Oct 21:30 UTC, MPG, 7 MB)
Terra ASTER image (8 October 2007, JPG, 152 KB, source: NASA)
AIRS SO2 product (1 October 2007, PDF, 484 KB, source: F. Prata, NILU)
Aura/OMI SO2 product (1 October 2007, JPG, 146 KB, source: S. Carn, UMBC)
Aura/OMI SO2 product (2 October 2007, JPG, 153 KB, source: S. Carn, UMBC)
Aura/OMI SO2 product (3 October 2007, JPG, 153 KB, source: S. Carn, UMBC)
New lava flows & ash/SO2 plumes from Mount Etna (29 March 2007)
Eruption of Mount Nyamuragira, Democratic Republic of the Congo (29 November 2006)
Meteosat-8 observing Karthala eruption (29 May 2006)
MSG observes stratospheric SO2 cloud from Soufriere Hills (21 May 2006)
Volcanic eruption of Mt. Karthala, Comoros (25 November 2005)
SEVIRI SO 2 Product
Full Area (GIF, 154 KB)
Animation (AVI, 6 MB)
(30 Sep 14:30 UTC–1 October 23:30 UTC)
(courtesy: F. Prata, Norwegian Inst. for Air Research)