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 Deep magma matters in volcanic eruption cycle Although the Soufriere Hills volcano on Montserrat exhibits cycles of eruption and quiet, an international team of researchers found that magma is continuously supplied from deep in the crust but that a valve acts below a shallower magma chamber, releasing lava to the surface periodically. Discovered: World's Largest Tsunami Debris A line of massive boulders on the western shore of Tonga may be evidence of the most powerful volcano-triggered tsunami found to date. Up to 9 meters (30 feet) high and weighing up to 1.6 million kilograms (3.5 million pounds), the seven coral boulders are located 100 to 400 meters (300 to 1,300 feet) from the coast. Extinct may not be forever for some species of Galapagos tortoises Yale scientists report that genetic traces of extinct species of Galapagos tortoises exist in descendants now living in the wild, a finding that could spur breeding programs to restore the species, The report appears in Proceedings of the National Academy of Sciences. Magmatically triggered slow earthquake discovered at Kilauea Volcano, Hawaii Kilauea experienced a new dike intrusion, where magma rapidly moved from a storage reservoir beneath the summit into the east rift zone and extended the rift zone by as much as 1 meter. Yellowstone's Ancient Supervolcano: Only Lukewarm? The geysers of Yellowstone National Park owe their eistence to the "Yellowstone hotspot"--a region of molten rock buried deep beneath Yellowstone, geologists have found. Up, Up and Away: Studying Volcanoes With Balloon People do all kinds of crazy things in Hawaii, but flying balloons over a volcano usually isn't one of them. Unless you're Adam Durant, that is. Robot Vehicle Surveys Deep Sea Off Pacific Northwest The first scientific mission with Sentry, a newly developed robot capable of diving as deep as 5,000 meters (3.1 miles) into the ocean, has been successfully completed by scientists and engineers from the Woods Hole Oceanographic Institution (WHOI) and the University of Washington (UW). New robot scouts best locations for components of undersea lab Like a deep-sea bloodhound, Sentry - the newest in an elite group of unmanned submersibles able to operate on their own in demanding and rugged environments - has helped scientists pinpoint optimal locations for two observation sites of a pioneering seafloor laboratory being planned off Washington and Oregon. Fire under the ice An international team of researchers was able to provide evidence of explosive volcanism in the deeps of the ice-covered Arctic Ocean for the first time. 1600 Eruption Caused Global Disruption The 1600 eruption of Huaynaputina in Peru had a global impact on human society, according to a new study of contemporary records by geologists at UC Davis. More Volcano Current Events and Volcano News Articles |
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