ESA's Envisat captures breath of volcanoJuly 12, 2007Indonesia's Mount Gamkonora volcano is spewing hot ash and smoke into the air, as seen in this image taken by the MERIS instrument aboard ESA's satellite Envisat, causing more than 8000 people to be evacuated amid fears of an imminent eruption, according to officials. Officials raised the alert to the highest level on Tuesday after the volcano, located in the eastern province of North Maluku, started spitting out flaming material, indicating magma was approaching the crater's surface making an eruption more likely, Saut Simatupang of Indonesia's Vulcanological Survey told Reuters news agency. The 1635m volcano, located about 2400 km northeast of Jakarta, began releasing smoke and ash on Saturday and spewed it as high as 4000m on Monday. Mount Gamkonora is the highest peak on Halmahera Island. Indonesia is located within the Pacific 'Ring of Fire', a continuous line (40 000 km long) of volcanoes and fault lines circling the edges of the Pacific Ocean, and has more than a hundred active volcanoes within its territory. The majority of the 1500 active volcanoes on the Earth's surface, of which around 50 erupt each year, are located along the Pacific 'Ring of Fire'. At least 500 million people live close to an active volcano. As world population increases, so does the potential threat from every eruption. Although there is no way ground-based monitoring can be carried out on all volcanoes across the globe, space-based monitoring helps identify the volcanoes presenting the greatest danger. Satellite radar, such as that aboard Envisat and ERS-2, allows scientists to track small changes in the Earth's movement that improves their ability to predict volcanic eruptions. Synthetic Aperture Radar Interferometry, InSAR for short, involves mathematically combining different radar images, acquired from as near as possible to the same point in space at different times, to create digital elevation models and reveal otherwise undetectable changes occurring between image acquisitions. Combined radar and optical data acquired from space are also very useful when an eruption begins. The synoptic view taken from optical and radar instruments aboard Envisat can simultaneously show the ash plume, the ash falling area, the lava streams and the volcanic cone shrinkage or expansion. Atmospheric sensors are used to identify the gases and aerosols released by the eruption, and quantify their wider environmental impact. Having access to these data over long periods of time is important for scientists to identify and analyse long-term trends and changes. ESA now has a 16-year archive of homogenous data thanks to the continuity of satellites ERS-1, ERS-2 and Envisat. Envisat and ERS-2, with a difference in overpass time of 30 minutes, are continually adding to the archive. To boost the use of Earth Observation (EO) data at volcanic observatories, ESA has started to monitor volcanoes worldwide within the framework of the Agency's Data User Element programme. The Globvolcano project, started in early 2007, will define, implement and validate information services to support volcanological observatories in their daily work by integration of EO data, with emphasis on observation and early warning. European Space Agency |
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| Related Volcano Current Events and Volcano News Articles Supervolcano eruption -- in Sumatra -- deforested India 73,000 years ago A new study provides "incontrovertible evidence" that the volcanic super-eruption of Toba on the island of Sumatra about 73,000 years ago deforested much of central India, some 3,000 miles from the epicenter, researchers report. Study uses satellite imagery to identify active magma systems in East Africa's Rift Valley A team from the University of Miami, University of El Paso and University of Rochester have employed Interferometric Synthetic Aperture Radar (InSAR) images compiled over a decade to study volcanic activity in the African Rift. The study, published in the November issue of Geology, studies the section of the rift in Kenya. African Desert Rift Confirmed as New Ocean in the Making In 2005, a gigantic, 35-mile-long rift broke open the desert ground in Ethiopia. At the time, some geologists believed the rift was the beginning of a new ocean as two parts of the African continent pulled apart, but the claim was controversial. HyBIS explores the Casablanca seamount In October, the hydraulic benthic interactive sampler HyBIS maintained by the National Oceanography Centre, Southampton (NOCS) made ten dives over the Casablanca Seamount, a four-kilometre high seamount located some 300 miles west of Morocco. Tsunami waves reasonably likely to strike Israel "There is a likely chance of tsunami waves reaching the shores of Israel," says Dr. Beverly Goodman of the Leon H. Charney School of Marine Sciences at the University of Haifa following an encompassing geo-archaeological study at the port of Caesarea. "Tsunami events in the Mediterranean do occur less frequently than in the Pacific Ocean, but our findings reveal a moderate rate of recurrence," she says. Scientists measure the rate of ascent of volcanic magma Plinian volcanic eruptions are notoriously destructive. These very powerful eruptions often occur after long periods of quiescence and are preceded by relatively short periods of seismic restiveness. 'Rosetta Stone' of supervolcanoes discovered in Italian Alps Scientists have found the "Rosetta Stone" of supervolcanoes, those giant pockmarks in the Earth's surface produced by rare and massive explosive eruptions that rank among nature's most violent events. The eruptions produce devastation on a regional scale - and possibly trigger climatic and environmental effects at a global scale. Researchers to study rebirth of an island after volcanic eruption When Alaska's Kasatochi Volcano erupted on Aug. 7, 2008, it virtually sterilized Kasatochi Island, covering the small Aleutian island with a layer of ash and other volcanic material several meters thick. UB Geologists to Help Communicate the Dangers of Colombian Volcano During the past decade, residents of Pasto, Colombia, and neighboring villages near Galeras, Colombia's most dangerous volcano, have been threatened with evacuation, but compliance varies. Obsidian 'trail' provides clues to how humans settled, interacted in Kuril Islands Archaeologists have used stone tools to answer many questions about human ancestors in both the distant and near past and now they are analyzing the origin of obsidian flakes to better understand how people settled and interacted in the inhospitable Kuril Islands. More Volcano Current Events and Volcano News Articles |
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