July 16, 2011 - Activity at Nabro volcano, Eritrea

Activity at Nabro volcano, Eritrea

On July 10, 2011 the Moderate Resolution Imaging Spectroradiometer aboard NASA’s Aqua satellite passed over Eritrea and captured this true-color image of the subsiding eruption of Nabro, a stratovolcano at the southeast end of the Danakil Alps.

Almost a month earlier, on June 12, a swarm of earthquakes shook the region, beginning near Afambo in Eritrea and moving southward about 100 km into Ethiopia. An explosive eruption of Nabro volcano followed, sending a large plume of ash, steam and sulfur dioxide up to 14,000 meters (8 miles) into the air. The ash plume traveled over 1,000 km (620 mi), and halted flights in East Africa for a time.

The Eritrean government reported seven casualties from the eruption, but news from the region is sparse. A report from Ethiopia’s Afar Disaster Prevention and Food Security Programs Coordination Office stated that 31 people had died as a result of the volcanic ash, and that reports of livestock mortality, migration, critical water shortage, human health problems and rising malnutrition due to the effects of ash were increasing. The areas most affected were identified as the woredas (districts) of Bido, Afdera, Erebti, Elidar, Teru and Kori in Ethiopia.

In this image, red marks a large hotspot, an area where the temperature is higher than the background. In this case the hotspot mostly likely represents oozing lava. A light haze appears to cover several areas west of the volcano, indicating that some steam or ash may continue to escape, even though no ash plume is evident. A large dark area extends southwest from the caldera. This is a layer of volcanic ash which covers the land.

To the west, Lake Afdera, normally blue in satellite images, appears a murky green. This lake is a hypersaline lake, and has been mined for rock salt for centuries. Ash from the eruption covered the lake shortly after the eruption. The contamination by ash, along with concerns about sulfur dioxide contamination of the salt, caused salt production to cease. By July 1, salt production had resumed.

Image Facts
Satellite: Aqua
Date Acquired: 7/10/2011
Resolutions: 1km ( B), 500m ( B), 250m ( B)
Bands Used: 1,4,3
Image Credit: Jeff Schmaltz, MODIS Land Rapid Response Team, NASA GSFC