21 Volcanoes Across Country Ready to Erupt
Candra Malik | October 01, 2010
In this file photo, Mount Sinabung, one of the 21 volcanoes being monitored for signs of danger. (JG Photo) Bandung. Twenty-one volcanoes across Indonesia could erupt at any time, leading to natural disasters, officials have warned.
An official from the Volcanology and Geological Disaster Mitigation Agency (PVMBG) told the Jakarta Globe on Friday that the alert for 18 volcanoes had been raised from Level 1, or "normal," to Level 2, or "beware."
Hendrasto, the head of the PVMBG's Volcano Observation Unit, said that three other volcanoes were on Level 3, or "standby," just one step below full alert, or Level 4.
One of those three is Mount Sinabung in Karo district, North Sumatra, which began erupting on Aug. 29 after lying dormant for 400 years. Its last major eruption, on Sept. 7, spewed volcanic ash more than 5,000 meters into the atmosphere.
"We downgraded Sinabung from Level 4 to Level 3 on September 23," Hendrasto said. "However, we still urge the public to remain alert for any danger."
Most of the villagers who were evacuated after the initial eruption have since been allowed to return to their homes.
The two other volcanoes on Level 3 alert are Mount Karangetang on Siau Island in North Sulawesi and Mount Ibu on Halmahera Island in North Maluku. Karangetang is considered the most active volcano in the archipelago, with 41 major eruptions since 1675. Its last eruption, on Aug. 6, is believed to have killed four people.
Ibu, meanwhile, has experienced ongoing eruptions since April 5, 2008, feeding a lava flow down one side of the mountain.
The 18 volcanoes on Level 2 alert include Papandayan in West Java, Slamet in Yogyakarta, Merapi in Central Java and Semeru and Bromo in East Java.
"Semeru and Slamet are the highest peaks in their provinces, while Bromo is a popular tourist destination," Hendrasto said. "Because of their popularity, we are urging the regional administrations to issue a warning advising the public of the raised alert status."
Other volcanoes on Level 2 alert include Talang in West Sumatra, Kaba in Bengkulu, Kerinci in Jambi and Anak Krakatau in the Sunda Strait, between Sumatra and Java.
Anak Krakatau is the remnant of Krakatau, whose violent eruption in August 1883 killed an estimated 40,000 people and was heard up to 5,000 kilometers away.
The eruption caused tsunamis as far away as South Africa, and resulted in global temperatures dropping by more than 1 degree Celsius.
Kerinci, at 3,800 meters, is the highest peak in Sumatra and the highest volcano in the country. It is a popular destination with hikers and wildlife enthusiasts because it lies inside the Bukit Barisan National Park.
In the east of the country, the Level 2 volcanoes are Batur in Bali, Sangeang Api and Rinjani in West Nusa Tenggara, Egon and Rokatenda in East Nusa Tenggara, Soputan and Lokon in North Sulawesi, and Dukono and Gamalama in North Maluku.
"Our officials will keep monitoring these volcanoes around the clock and provide real-time updates," Hendrasto said.
All 21 volcanoes highlighted have erupted sometime this year, and are among 59 active volcanoes across the country.
----------------------------------------------------------------------------------------------------------------------------------------------------------------------
An island's rebirth: Life emerges after a catastrophic volcanic eruption
Released: 8/25/2010 12:47:16 PM
Anchorage, Alaska — A secluded island in the Aleutian chain is revealing secrets of how land and marine ecosystems react to and recover from a catastrophic volcanic eruption that appeared at first glance to destroy all life on the island.
Yet little by little – a wingless beetle here, a tuft of grass there, Kasatochi, an island in the Alaska Maritime National Wildlife Refuge rarely studied by scientists before its Aug. 7, 2008, volcanic eruption, is showing signs of recovery.
In the summer of 2009, scientists with the U.S. Geological Survey, U.S. Fish and Wildlife Service, and the University of Alaska Museum of the North returned to the island to begin long-term studies to better understand the effects of the eruption and how quickly the island's ecosystems recover.
 |
| Kasatochi volcano, Alaska, after its eruption on Aug. 7, 2008. Picture taken at 17,000 feet above seal level. Picture courtesy of Jerry Morris. |
 |
| Summit crater and crater lake of Kasatochi volcano, August 6, 2008, the day before the eruption. The crater shown here is about 4,000 feet in diameter. Photo by Chris Ford, USFWS. |
Despite the frequency of volcanic eruptions in Alaska, this is one of the first studies of its kind in the remote Aleutian Islands. Their findings are detailed in a series of 10 reports published in the August 2010 issue of the journal Arctic, Antarctic, and Alpine Research.
Prior to the eruption, Kasatochi was one of the most picturesque of the Aleutian Islands. Its steep slopes were covered with low-growing grasses and wildflowers, and in the center of the island there was a steep-walled crater filled at the bottom with a small turquoise lake.
Kasatochi Island hosted a colony of about 250,000 least and crested auklets, making it one of the major seabird breeding colonies in the Aleutian Islands. In turn, the numerous seabirds attracted avian predators such as bald eagles, peregrine falcons and ravens. Kasatochi Island was also home to a rookery of endangered Steller sea lions.
But after the eruption, other than sea lions loafing on a newly formed beach, the island appeared to be completely devoid of life. The entire island and neighboring seafloor were covered with thick layers of volcanic ash and deposits from the eruption.
That first summer after the eruption, teams of geologists, botanists, entomologists, ornithologists and marine ecologists visited Kasatochi and nearby islands four times to document the effects of the eruption and establish a baseline with which long-term observations will be compared. The team also set up sampling plots and equipment such as seismometers, time-lapse cameras and bird song recorders.
"When we first landed on the island, we were unsure of what we would find," said project manager Tony DeGange of the USGS. "The formerly lush, green island was uniformly gray and in the 10 months since the eruption, considerable erosion of volcanic ash had occurred."
By late summer, the team found several kinds of green plants scattered around the island.
"Even more exciting was the discovery of one small remnant plant community," said USGS research geneticist Sandra Talbot. "Most of the plants likely originated from underground root systems, rhizomes or seed banks that survived the eruption, particularly in areas that were protected from the hot volcanic flows and where the ash eroded off quickly to expose the pre-eruption soils."
Entomologist Derek Sikes from the University of Alaska Museum of the North also discovered that terrestrial arthropods had survived the eruption. He found wingless carrion beetles, a centipede and a spider, as well as kelp flies and a blowfly that were eating bird carcasses and kelp that had washed up on the island.
Thousands of seabirds returned to the island that first summer, although none nested successfully, according to Jeff Williams of the U.S. Fish and Wildlife Service's Alaska Maritime National Wildlife Refuge.
"The auklet colony was buried under volcanic debris and ash," Williams said. "They were unable to locate suitable nesting crevices and laid eggs on the ground or in the water instead. It will be interesting to see if erosion eventually exposes the rock crevices that these birds need for nesting or if they eventually abandon the island. Steller sea lions," he added, "were the only wildlife species to breed successfully."
Similar to what the research team found onshore, nearshore habitats were blanketed with sediments and were largely devoid of life. Most of the kelp forests in the ocean around the island had been covered with volcanic debris.
"We are now in the midst of our second year of research at Kasatochi Island, and our intent is to continue this work for many years," said DeGange. "The Aleutian Islands are a part of the Pacific ring of fire, and destructive volcanic eruptions are a primary form of ecosystem disturbance in these earthquake- and volcano-prone zones that reach from Chile up to Alaska and down through the South Pacific. Kasatochi Island is a natural laboratory that will help us understand how volcanic eruptions shape Aleutian Island ecosystems."
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
NASA image Shiveluch and Klyuchevskoy display plumes of ash
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
You really must see this footage--up close and personal with a volcano
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
--
Got Penguins?
Penguin News Today
The Science of Penguins
Gentoo Penguins of Gars O'Higgins Station, Antarctica
>^,,^<
__._,_.___
No comments:
Post a Comment