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Earth from Space – Eruption in the Red Sea

Satellite image of a volcanic eruption in the Zubair Group

NASA Earth Observing-1 (EO-1) satellite image of a volcanic eruption in the Zubair Group of islands in the Red Sea.

AN ERUPTION OCCURRED in the Red Sea in December 2011. According to news reports, fishermen witnessed lava fountains reaching up to 30 metres tall on December 19.

The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra and Aqua satellites observed plumes on December 20 and December 22. Meanwhile, the Ozone Monitoring Instrument (OMI) on NASA’s Aura satellite detected elevated levels of sulphur dioxide, further indicating an eruption.

The activity in the Red Sea included more than an eruption. By December 23, 2011, what looked like a new island had appeared.

The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured these high-resolution, natural-colour images on December 23, 2011 (above), and October 24, 2007 (below).

Satellite image of Zubair Group islands

A satellite image of the same region, taken in 2007, shows no sign of the new volcanic island.

The image from December 2011 shows an apparent island where there had previously been an unbroken water surface. A thick plume rises from the island, dark near the bottom and light near the top, perhaps a mixture of volcanic ash and water vapour.

The volcanic activity occurred along the Zubair Group, a collection of small islands off the west coast of Yemen. Running in a roughly northwest-southeast line, the islands poke above the sea surface, rising from a shield volcano.

This region is part of the Red Sea Rift where the African and Arabian tectonic plates pull apart and new ocean crust regularly forms.

Wider satellite image of a volcanic eruption in the Zubair Group

This wider view shows more of the islands in the Zubair Group.

Close up satellite image of a volcanic eruption in the Zubair Group

And this close up gives a better view of the new island and the huge plume of smoke and steam.

NASA Earth Observatory image created by Jesse Allen, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Text adapted from information issued by Michon Scott.

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Iceberg’s break from Matusevich Glacier

Matusevich Glacier iceberg calves

NASA's Earth Observing-1 (EO-1) satellite spotted large icebergs calving from the Matusevich Glacier in East Antarctica.

The Matusevich Glacier flows toward the coast of East Antarctica, pushing through a channel between the Lazarev Mountains and the northwestern tip of the Wilson Hills.

Constrained by surrounding rocks, the river of ice holds together. But stresses resulting from the glacier’s movement make deep crevasses, or cracks, in the ice.

After passing through the channel, the glacier has room to spread out as it floats on the ocean. The expanded area and the jostling of ocean waves prompts the ice to break apart, which it often does along existing crevasses.

See the full-size, high-resolution image here (will open in a new window or tab).

On September 6, 2010, the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured this natural-colour image of the margin of Matusevich Glacier.

Shown here just past the rock-lined channel, the glacier is calving large icebergs. Low-angled sunlight illuminates north-facing surfaces and casts long shadows to the south. Fast ice anchored to the shore surrounds both the glacier tongue and the icebergs it has calved.

Compared to the glacier and icebergs, the fast ice is thinner with a smoother surface. Out to sea (image left), the sea ice is even thinner and moves with winds and currents.

Matusevich Glacier does not drain a significant amount of ice off the Antarctic continent, so the glacier’s advances and retreats lack global significance. Like other Antarctic glaciers, however, Matusevich helps glaciologists form a larger picture of Antarctica’s glacial health and ice sheet volume.

NASA Earth Observatory image created by Jesse Allen and Robert Simmon, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Text adapted from information issued by Michon Scott (NASA Earth Observatory) based on image interpretation by Robert Bindschadler, NASA Goddard Space Flight Centre, and Walt Meier, National Snow and Ice Data Centre.

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