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Earth from Space – Roze Glacier

Satellite image of Roze Glacier

Russia's remote Severny Island is home to the huge Roze Glacier.

PART OF THE RUSSIAN FEDERATION, the archipelago of Novaya Zemlya consists of two big islands—Yuzhny in the southwest, and Severny in the northeast—separated by a narrow strait. The archipelago divides the Barents Sea from the Kara Sea.

An ice cap covers much of Severny, and from this ice cap, several outlet glaciers flow seaward. The easternmost glacier on Severny’s southeastern coast is Roze.

On June 5, 2011, the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured this natural-colour image of Roze Glacier fringed by sea ice.

The glacier pushes slowly seaward between two rocky ridges. Uneven snow cover on the rock surfaces creates a patchwork of brown and white. Some snow also rests on the adjacent sea ice, which appears in shades of white and gray. In the east, a large patch of gray ice immediately offshore may owe its colour to a layer of melt water or simply a lack of snow cover.

On the glacier itself, isolated pools of melt water form ovals and slivers of blue-gray. Dwarfing the melt ponds, two long parallel stripes extend southward toward the coast. The stripes look like debris along the sides of a relatively fast-flowing ice stream, which may have picked up rocks and dirt from an upslope rock outcrop.

Glaciers gain ice through snow accumulation, and lose it through melting and calving icebergs. A report released in 2006 by the Laboratoire d’Etudes en Géophysique et Océanographie Spatiales stated that Roze Glacier, in addition to other glaciers along Severny’s southeastern coast, underwent overall ice loss between 1990 and 2000.

Several hundred years ago, the Little Ice Age prompted many glaciers to advance. Glaciers do not respond to changing climate immediately, but may advance or retreat years, decades, even centuries afterwards.

A study published in 2009 reported that the glaciers on Novaya Zemlya likely reached their maximum extent related to the Little Ice Age near the end of the nineteenth century, and have since retreated at varying rates.

See the full-size image of Roze Glacier here.

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 based on image interpretation by Walt Meier, National Snow and Ice Data Centre.

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Russia’s twin volcanoes

Klyuchevskaya and Bezymianny volcanoes on Russia's Kamchatka Peninsula.

A satellite image of the Klyuchevskaya and Bezymianny volcanoes erupting on Russia's Kamchatka Peninsula.

Neighbouring volcanoes on Russia’s Kamchatka Peninsula acted up at the same time in mid-February 2010. Klyuchevskaya Volcano in the north and Bezymianny Volcano in the south both sent plumes skyward over a snowy landscape. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite captured this false-colour image on February 13, 2010.

Low-angled sunlight illuminates the southern slopes of Kamchatka’s rugged landscape, as well as the southern sides of both volcanic plumes. The plumes’ light colour suggests that, of the visible material in each plume, steam predominates over volcanic ash. Both plumes cast shadows toward the northwest.

Reaching a height of 4,835 metres (15,860 feet), Klyuchevskaya (also Kliuchevskoi) Volcano is both the tallest and most active volcano on Kamchatka. It is a stratovolcano—a steep-sloped, conical structure composed of alternating layers of solidified ash, hardened lava, and rock fragments ejected by earlier eruptions.

On February 11, 2010, the Kamchatka Volcanic Eruption Response Team (KVERT) reported above-background seismic activity at Klyuchevskaya Volcano, including gas and/or steam plumes reaching 6 kilometres (20,000 feet) above sea level, lava flows, and Strombolian eruptions—intermittent explosions or fountains of rock—roughly 300 metres (1,000 feet) above the volcano’s summit.

Dwarfed by its neighbour, Bezymianny reaches 2,882 metres (9,455 feet) above sea level. Compared to the volcano immediately to the north, it releases a smaller, thinner plume. Like Klyuchevskaya, Bezymianny is also a stratovolcano.

On February 11, KVERT reported that Bezymianny was releasing plumes that could affect low-flying aircraft, and it might have experienced a moderate explosive event on February 5-6, 2010. More significant seismic activity at Klyuchevskaya, however, obscured data from Bezymianny.

Kamchatka lies along the Pacific Ring of Fire—a seismically active area encircling the Pacific Ocean. Both Klyuchevskaya and Bezymianny were intermittently active in late 2009 and early 2010.

NASA Earth Observatory image created by Jesse Allen, using data provided courtesy of NASA / GSFC / METI / ERSDAC / JAROS, and the US / Japan ASTER Science Team. Text adapted from information issued by Michon Scott.