SUBHEAD: Every time in recorded history that Eyjafjallajokull volcano has erupted, the much larger Katla volcano has also erupted. Scientists are watching Katla carefully.
By Bryan Walsh on 16 April 2010 in Time -
(http://www.time.com/time/health/article/0,8599,1982787,00.html)
Image above: Photo by Rakel Osk Sigurda of horses escaping Iceland's Eyjnafjallajökull volcanic dust cloud. From (http://www.time.com/time/photogallery/0,29307,1982747_2126706,00.html).
As volcanoes go, the eruption of Iceland's Eyjafjallajokull on Tuesday, April 13, won't make the science books. Though scientists haven't yet been able to gather enough information on the eruption to give it a score on the Volcanic Explosivity Index — which ranks volcanic events on a 1-to-8 scale — it's unlikely to score very high.
Eyjafjallajokull barely compares to major eruptions like Mount St. Helens in 1980, which released 1.5 million metric tons of sulfur dioxide into the atmosphere, or the catastrophe of Krakatoa in Indonesia in 1883, which killed more than 40,000 people and was felt around the world. During Eyjafjallajokull, by contrast, there have been no deaths, and just 800 people living near the volcano had to be evacuated.
But Eyjafjallajokull's eruption has still had a major impact on the world, as its 7-mile-high plume of volcanic gases and silicate ash has spread across much of Europe, bringing air travel across the continent to a near standstill. Britain's airspace is still closed, and authorities don't expect to loosen restrictions until sometime Saturday at the earliest. On Friday, two-thirds of European flights were canceled, as were 180 transatlantic flights. Delays and cancellations hit airports from Toronto to Tokyo, and the problems have cost the global air-travel industry an estimated $200 million a day. Not bad for a distinctly minor-league eruption. (See a gallery of the eerie beauty of the eruption.)
Still, the havoc caused by Eyjafjallajokull is a reminder that in our globalized, interconnected world, it's less the sheer power of a natural disaster than where and when it happens — and how prepared we are to respond. Eyjafjallajokull was at the right place at the right time to wreak maximum havoc on air travel. (Even relatively small amounts of volcanic ash high in the air can clog sensitive jet engines, shutting down ventilation and causing the machinery to melt down and fail.) If the volcano had erupted in the years before air travel became common, it wouldn't have caused trouble for anyone but the people of Iceland.
The same goes for other kinds of natural disasters. The earthquake that hit Haiti in January killed some 230,000 people, yet the temblor registered only a 7.0 on the Richter scale — bad, but not that bad. In fact, the quake barely compared to the 8.8 temblor that hit Chile a little more than a month later, killing fewer than 500 people.
What's the difference? Population density — the Haiti quake struck the country's dense capital of Port-au-Prince, while the Chile one missed big cities like Santiago — and preparation. Chile is a relatively well-off South American nation with a long history of earthquakes, so its buildings are designed to resist seismic waves, and the government and people know how to respond to a disaster. Impoverished Haiti, by contrast, was helpless, and its people paid the price. (See how some people fought the ash to try to reach their destinations.)
As global populations have grown and people have crowded into risk zones — like earthquake areas and flood plains — the toll of natural disasters has grown as well. According to the Center for Research on Epidemiology of Disasters, the number of catastrophic events has more than doubled since the 1980s, and the Red Cross estimates that the economic damage from disasters rose fivefold, to $629 billion, from 1985 to 2005. That doesn't necessarily mean that volcanoes and quakes are getting worse — but rather that there are more of us living in areas where we might be affected by a disaster, and we have more to lose.
Fortunately, global wealth and technology allow us to better prepare for and respond to natural disasters. In the case of the Eyjafjallajokull eruption, European air-traffic controllers already had plans in place to deal with ash clouds. Shutting down the continent's airspace and grounding thousands of flights was expensive and inconvenient, but it was far preferable to having planes fall out of the sky. And while the economic toll of such disasters may be rising, huge death tolls are far less common.
By Bryan Walsh on 16 April 2010 in Time -
(http://www.time.com/time/health/article/0,8599,1982787,00.html)
Image above: Photo by Rakel Osk Sigurda of horses escaping Iceland's Eyjnafjallajökull volcanic dust cloud. From (http://www.time.com/time/photogallery/0,29307,1982747_2126706,00.html).
As volcanoes go, the eruption of Iceland's Eyjafjallajokull on Tuesday, April 13, won't make the science books. Though scientists haven't yet been able to gather enough information on the eruption to give it a score on the Volcanic Explosivity Index — which ranks volcanic events on a 1-to-8 scale — it's unlikely to score very high.
Eyjafjallajokull barely compares to major eruptions like Mount St. Helens in 1980, which released 1.5 million metric tons of sulfur dioxide into the atmosphere, or the catastrophe of Krakatoa in Indonesia in 1883, which killed more than 40,000 people and was felt around the world. During Eyjafjallajokull, by contrast, there have been no deaths, and just 800 people living near the volcano had to be evacuated.
But Eyjafjallajokull's eruption has still had a major impact on the world, as its 7-mile-high plume of volcanic gases and silicate ash has spread across much of Europe, bringing air travel across the continent to a near standstill. Britain's airspace is still closed, and authorities don't expect to loosen restrictions until sometime Saturday at the earliest. On Friday, two-thirds of European flights were canceled, as were 180 transatlantic flights. Delays and cancellations hit airports from Toronto to Tokyo, and the problems have cost the global air-travel industry an estimated $200 million a day. Not bad for a distinctly minor-league eruption. (See a gallery of the eerie beauty of the eruption.)
Still, the havoc caused by Eyjafjallajokull is a reminder that in our globalized, interconnected world, it's less the sheer power of a natural disaster than where and when it happens — and how prepared we are to respond. Eyjafjallajokull was at the right place at the right time to wreak maximum havoc on air travel. (Even relatively small amounts of volcanic ash high in the air can clog sensitive jet engines, shutting down ventilation and causing the machinery to melt down and fail.) If the volcano had erupted in the years before air travel became common, it wouldn't have caused trouble for anyone but the people of Iceland.
The same goes for other kinds of natural disasters. The earthquake that hit Haiti in January killed some 230,000 people, yet the temblor registered only a 7.0 on the Richter scale — bad, but not that bad. In fact, the quake barely compared to the 8.8 temblor that hit Chile a little more than a month later, killing fewer than 500 people.
What's the difference? Population density — the Haiti quake struck the country's dense capital of Port-au-Prince, while the Chile one missed big cities like Santiago — and preparation. Chile is a relatively well-off South American nation with a long history of earthquakes, so its buildings are designed to resist seismic waves, and the government and people know how to respond to a disaster. Impoverished Haiti, by contrast, was helpless, and its people paid the price. (See how some people fought the ash to try to reach their destinations.)
As global populations have grown and people have crowded into risk zones — like earthquake areas and flood plains — the toll of natural disasters has grown as well. According to the Center for Research on Epidemiology of Disasters, the number of catastrophic events has more than doubled since the 1980s, and the Red Cross estimates that the economic damage from disasters rose fivefold, to $629 billion, from 1985 to 2005. That doesn't necessarily mean that volcanoes and quakes are getting worse — but rather that there are more of us living in areas where we might be affected by a disaster, and we have more to lose.
Fortunately, global wealth and technology allow us to better prepare for and respond to natural disasters. In the case of the Eyjafjallajokull eruption, European air-traffic controllers already had plans in place to deal with ash clouds. Shutting down the continent's airspace and grounding thousands of flights was expensive and inconvenient, but it was far preferable to having planes fall out of the sky. And while the economic toll of such disasters may be rising, huge death tolls are far less common.
In 1783, the volcano Laki in Iceland erupted on a massive scale, throwing so much ash and sulfur dioxide into the atmosphere that it led to a famine that killed half of Iceland's livestock and 25% of its population. An eruption of that size today likely wouldn't cause nearly as dramatic a death toll — though it might well interrupt flyers for weeks or even months. (See why volcanic ash is a health issue for air travelers.)
Authorities hope Eyjafjallajokull will quiet down in the days to come and the ash cloud will disperse, allowing European air travel to return to normal — although its last eruption, in 1821, went on for two years. Yet the volcano's worldwide impact should not have come as a surprise, considering the fallout from Iceland's economic collapse in 2008, which affected borrowers across Europe. In natural disasters as well as the financial system, what happens in Iceland doesn't always stay in Iceland.
'Angry Sister' Katla
By Mark Sappenfield on 18 April 2010 in C.S. Monitor -
(http://www.csmonitor.com/Science/2010/0418/Iceland-s-Eyjafjallajoekull-volcano-is-nothing-to-Angry-
Image above: Lightning, fire, smoke, and molten glass swirl above Eyjafjallajokul volcano on 4/17/10. From (http://www.csmonitor.com/CSM-Photo-Galleries/In-Pictures/Iceland-volcano/%28photo%29/13) Sister-Katla)
This history of Iceland will not make for comforting reading for thousands of would-be air travelers stranded across northern Europe and beyond. The last time Eyjafjallajökull erupted, it continued belching the Earth's unsettled insides for 14 months, from December 1821 to January 1823.
Scientists do not expect Eyjafjallajökull to keep northern Europe's airports closed for 14 months, but they suggest that Eyjafjallajökull's impact on world travel might not end with the end of this current eruption.
Moreover, Iceland's "Angry Sister" hasn't even awoken yet. The three times in recorded history when Eyjafjallajökull has erupted, its neighbor, the much larger Katla, has followed suit.
Data do not yet suggest that a Katla eruption is imminent. Yet, in some respects, it is the far greater concern, both in Iceland and beyond.
Katla: the sleeping sister
Katla has erupted 16 times since 930AD. In 1755 it exploded so violently that its ash settled on parts of Scotland. In 1918, Katla tore chunks of ice the size of houses from the Myrdalsjökull glacier atop it, sending them careening down its slopes and into the Atlantic on floods of melted glacier water.
While Eyjafjallavökull is virtually anonymous in Icelandic lore, Katla is one of the "Angry Sisters" along its even-more active twin, Hekla.
The 1918 eruption was the last major eruption of Katla – a volcano that has erupted twice a century, on average – which is why scientists have paid particularly close attention to it in recent days.
But while earth beneath Eyjafjallajökull trembled with thousands of small earthquakes in the months before the eruption – signaling that magma was welling up beneath the volcano – scientists have not seen the same activity at Katla yet.
Even as some scientists suggest that the current Eyjnafjallajökull eruption is abating, the past few days have been only a taste of what Icelanders have known for generations: Their island is one of the most restless places on the planet.
In 1973, an eruption near the nation's primary fishing port split the island of Heimaey in two and required its entire population to be evacuated to the Icelandic mainland by fishing boat.
On 1783, one-quarter of Iceland's population was killed when Laki erupted – an eruption so massive that it changed global weather patterns, bringing record snow to New Jersey and drought to Egypt.
And in the 1755 Katla eruption, the volume of floodwaters from the Myrdalsjökull glacier were estimated to be equal to or greater than the discharge of water from the Amazon, Nile, and Mississippi Rivers combined.
Iceland: an Arctic thread of fire
Much like lands atop the Pacific Ring of Fire, Iceland sits atop a seam in earth's crust, straddling two of the planet's tectonic puzzle pieces.
In other such places, such as Chile, one piece of crust is sliding beneath the other, pushing up the Andes mountains. But in Iceland, new earth is being born with every eruption.
Along the tectonic border marked by Iceland's volcanoes, the world is spreading, gradually pushing Iceland's halves – and the plates they sit on – farther apart. The volcanoes are making new crust, their liquid rock cooling into new landscapes, eruption by eruption, foot by foot.
In this way, Eyjafjallajökull is merely part of the ancient tectonic dance of the continents. But some scientists suggest that the changing global climate could make Icelandic eruptions more common.
As Iceland's glaciers thin, their weight upon the island's volcanoes will lighten, making it easier for magma to rise from the earth's depths, they say..
Authorities hope Eyjafjallajokull will quiet down in the days to come and the ash cloud will disperse, allowing European air travel to return to normal — although its last eruption, in 1821, went on for two years. Yet the volcano's worldwide impact should not have come as a surprise, considering the fallout from Iceland's economic collapse in 2008, which affected borrowers across Europe. In natural disasters as well as the financial system, what happens in Iceland doesn't always stay in Iceland.
'Angry Sister' Katla
By Mark Sappenfield on 18 April 2010 in C.S. Monitor -
(http://www.csmonitor.com/Science/2010/0418/Iceland-s-Eyjafjallajoekull-volcano-is-nothing-to-Angry-
Image above: Lightning, fire, smoke, and molten glass swirl above Eyjafjallajokul volcano on 4/17/10. From (http://www.csmonitor.com/CSM-Photo-Galleries/In-Pictures/Iceland-volcano/%28photo%29/13) Sister-Katla)
This history of Iceland will not make for comforting reading for thousands of would-be air travelers stranded across northern Europe and beyond. The last time Eyjafjallajökull erupted, it continued belching the Earth's unsettled insides for 14 months, from December 1821 to January 1823.
Scientists do not expect Eyjafjallajökull to keep northern Europe's airports closed for 14 months, but they suggest that Eyjafjallajökull's impact on world travel might not end with the end of this current eruption.
Moreover, Iceland's "Angry Sister" hasn't even awoken yet. The three times in recorded history when Eyjafjallajökull has erupted, its neighbor, the much larger Katla, has followed suit.
Data do not yet suggest that a Katla eruption is imminent. Yet, in some respects, it is the far greater concern, both in Iceland and beyond.
Katla: the sleeping sister
Katla has erupted 16 times since 930AD. In 1755 it exploded so violently that its ash settled on parts of Scotland. In 1918, Katla tore chunks of ice the size of houses from the Myrdalsjökull glacier atop it, sending them careening down its slopes and into the Atlantic on floods of melted glacier water.
While Eyjafjallavökull is virtually anonymous in Icelandic lore, Katla is one of the "Angry Sisters" along its even-more active twin, Hekla.
The 1918 eruption was the last major eruption of Katla – a volcano that has erupted twice a century, on average – which is why scientists have paid particularly close attention to it in recent days.
But while earth beneath Eyjafjallajökull trembled with thousands of small earthquakes in the months before the eruption – signaling that magma was welling up beneath the volcano – scientists have not seen the same activity at Katla yet.
Even as some scientists suggest that the current Eyjnafjallajökull eruption is abating, the past few days have been only a taste of what Icelanders have known for generations: Their island is one of the most restless places on the planet.
In 1973, an eruption near the nation's primary fishing port split the island of Heimaey in two and required its entire population to be evacuated to the Icelandic mainland by fishing boat.
On 1783, one-quarter of Iceland's population was killed when Laki erupted – an eruption so massive that it changed global weather patterns, bringing record snow to New Jersey and drought to Egypt.
And in the 1755 Katla eruption, the volume of floodwaters from the Myrdalsjökull glacier were estimated to be equal to or greater than the discharge of water from the Amazon, Nile, and Mississippi Rivers combined.
Iceland: an Arctic thread of fire
Much like lands atop the Pacific Ring of Fire, Iceland sits atop a seam in earth's crust, straddling two of the planet's tectonic puzzle pieces.
In other such places, such as Chile, one piece of crust is sliding beneath the other, pushing up the Andes mountains. But in Iceland, new earth is being born with every eruption.
Along the tectonic border marked by Iceland's volcanoes, the world is spreading, gradually pushing Iceland's halves – and the plates they sit on – farther apart. The volcanoes are making new crust, their liquid rock cooling into new landscapes, eruption by eruption, foot by foot.
In this way, Eyjafjallajökull is merely part of the ancient tectonic dance of the continents. But some scientists suggest that the changing global climate could make Icelandic eruptions more common.
As Iceland's glaciers thin, their weight upon the island's volcanoes will lighten, making it easier for magma to rise from the earth's depths, they say..
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