Saturday, August 13, 2011

Ash cloud Geology

Ash cloud Geology

Ash cloud Geology. The Anabro (Nabro) volcano in the Northern Red Sea Region of Eritrea has erupted sending an ash plume more than 13.5 kilometres into the sky and disrupting air traffic across eastern Africa. Part of the Afar Triangle, the stratovolcano is one of many volcanic caldera complexes in the north easternmost part of the East African Rift valley region. Nabro is located in the Danakil Depression, close to Eritrea’s border with Ethiopia and north of Djibouti, and has not erupted in at least 150 years. It is the most prominent of 3 large volcanoes (Nabro, Dubbi, Mallahle) in the region, each containing a large summit caldera.The volcano erupted at 2103 GMT Sunday evening. The Volcanic Ash Advisory Center (VAAC) said Monday that the 5,331 ft volcano has resulted in a large ash plume of up to 13.5 kilometres (8 miles) high. The scale of the eruption, compared to the ongoing eruption in Chile and 2010′s eruption at Eyjafjallaj√∂kull in Iceland, remains unclear.

The eruption was preceded by seven moderate earthquakes yesterday afternoon. A 5.6 magnitude quake at 21.03 GMT signalled the start of the eruption. The quake was centred 48 km south of the town of Edd (pop 11,259) and 199 km southwest of the city of Al-h’udaydah (pop 617,871). A 4.6 magnitude quake followed less than 35 minutes later.

On Monday afternoon officials in Ethiopia warned citizens to protect themselves from the ash and smoke coming from the volcanic eruption. says ash is falling on the northern Ethiopian town of Mekele. Asamara, the capital city of Eritrea, is also said to be affected by ash from the erupting volcano. Ethiopian Airlines confirmed that all air services are operating as normal at present (1700hrs GMT). However, German airline Lufthansa said Thursday evening it had cancelled flights to Eritrea and Ethiopia.

Meanwhile, the latest ash advisory issued by the VAAC (see below graphic) is predicting that the Ash plume will spread towards the Middle East Monday night. By 6am Tuesday the ash plume is expected get caught in a west-to-east jet stream and spread to the skies over parts of Egypt, Sudan, Eritrea, Ethiopia, Djibouti, Somalia, Israel, Jordan, Yemen, Saudi Arabia and Iraq.

The Jerusalem Post reported Monday evening that the ash plume may cause disruption to air traffic in Israel, Egypt, Jordan. “For now it looks like the ash is going to arrive to our southern border around Eilat southeast of us,” said Evgeny Brainin, a forecaster for Israel Meteorological Service. “It’s not likely to go Israel, but around us, perhaps to Jordan and Saudi Arabia even by tonight.

Read more: irishweatheronline