Photos

At the top left, the capital city of Sudan, Khartoum, is located at the convergence of the Blue Nile and the White Nile. Although the Blue Nile is much shorter than the White Nile, it contributes about 80% of the flow of the river. The Dahlak Archipelago is seen off the Red Sea coast of Eritrea. Because of their isolation, the numerous coral reefs of the Dahlak Archipelago are some of the most pristine in the world. North of the Rift Valley, in central Ethiopia, are the Simien Mountains and Lake Tana. Lake Tana is the source of the Blue Nile. Photo courtesy of NASA.

The stratovolcano, Nabro, rumbled to life on 12 June 2011, following a series of earthquakes. This satellite image was taken the following day. There had been no previous historical reports of eruptions at Nabro. Photo courtesy of NASA.

Astronaut photo of Nabro, taken 4½ months before the June 2011 eruption. Before its 2011 eruption, the volcano was widely believed to be extinct. Image courtesy of NASA.

Satellite view of the Nabro Volcano taken on 24 June 2011. The bright red areas indicate hot surfaces. Hot volcanic ash glows above the vent, located in the center of Nabro’s caldera. To the west of the vent, portions of an active lava flow (particularly the front of the flow) are also hot. The speckled pattern on upstream portions of the flow are likely due to the cool, hardened crust splitting and exposing fluid lava as the flow advances. The bulbous blue-white cloud near the vent is likely composed largely of escaping water vapor that condensed as the plume rose and cooled. The whispy, cyan clouds above the lava flow are evidence of degassing from the lava. Image courtesy of NASA.

View of the Nabro Volcano as of 29 June 2011 shows the extent of the lava flow and that the intensity of the eruption has abated somewhat. The eruption continued for many more weeks. Image courtesy of NASA.