Named after an evil troll, Katla has a larger magma chamber than Eyjafjallajokul's. Its last major eruption in 1918 continued more than a month, turning day into night, starving crops of sunlight and killing off some livestock. The eruption melted some of the ice-sheet covering Katla, flooding surrounding farmlands with a torrent of water that some accounts have said measured as wide as the Amazon. Now, clusters of small earthquakes are being detected around Katla, which means an eruption could be imminent, seismologists say. The earthquakes have been growing in strength, too. After a long period of magnitude 3 tremors, a magnitude 4 quake was detected last week. "It is definitely showing signs of restlessness."
Teams of seismologists and geologists at the university are tracking the spike in seismic activity and working with disaster officials to prepare communities near Katla like Vik, a small town of some 300 people. Civil defense authorities have been holding regular meetings with scientists. Disaster officials have also drafted an evacuation plan and set aside temporary housing, but many fear they may have less than an hour to evacuate once the volcano erupts. Records show that Katla usually has a large eruption twice a century. Since its last eruption was almost exactly 93 years ago, it is long overdue for another, seismologists say. "There is most definitely increased activity. The question is whether it calms down after this or whether there is an eruption."
The eruption of Laki in 1783 was one of Iceland's deadliest. It freed poisonous gases that turned into smog and floated across the jet stream, killing thousands of people with toxic fumes in the British Isles alone. As sulfur dioxide was pumped into the atmosphere, crop production fell across western Europe because of the smog. Famine spread. And the sun reportedly turned a blood-red hue — a phenomenon painted by many artists of the time. Temperatures in Europe were about 2 degrees Celsius (3.6 degrees Fahrenheit) below average. The winter of 1784 was also reportedly one of the longest and coldest on record in North America, with the Mississippi River freezing in New Orleans. Scientists believe volcanic ash floating over the Atlantic was a factor. "Volcanoes can be quite beautiful, but they can also obviously be quite destructive."
Of Iceland's more than 22 volcanoes, seven are active and four are particularly active — including Katla and Hekla. Although it doesn't pose the same flood risk as Katla because it's not situated beneath an icecap, Hekla is one of Iceland's most active volcanoes and sits in the path of most international flight patterns. Like Katla, Hekla is also overdue for a large eruption and could produce a disruptive and dangerous ash cloud that, in addition to disrupting air travel, could lower overall temperatures across continents by blocking out sunlight for days or weeks.
The capital Reykjavik also sits on a plate boundary but it hasn't seen any eruptions for some 800 years. Still, one of the plates is showing an uplift, or expansion of the crust, which could mean either that a volcano could be nearing an eruption or there is an increase of geothermal activity. Much of Iceland's infrastructure was built during a lull in volcanic activity. "One of these days that situation will change and we will definitely see more eruptions close to Reykjavik."
Going to bed at night saying we’ve done something wonderful –
that’s what matters.**
LARGEST QUAKES -
This morning -
5.6 AMURSKAYA OBLAST', RUSSIA
6.7 EASTERN NEW GUINEA REG., P.N.G.
5.0 SOUTH OF BALI, INDONESIA
6.1 SOUTH OF BALI, INDONESIA
5.3 MARIANA ISLANDS REGION
5.2 NORTHERN PERU
5.6 OFF COAST OF OREGON
Quake debris clean-up at halfway point in Haiti - Haiti still faces a massive reconstruction effort following the January 12, 2010 quake, which killed more than 300,000 people and caused massive damage in the poorest country in the Americas.
Volcano experts in Spain's Canary Islands say the threat of an eruption on Hierro island has eased after pressure in the area was reduced following the undersea event this week.
Possible 'super volcano' trigger - A catastrophic so-called super-eruption of a major volcanic system happens about every 100,000 years, and U.S. researchers say they've found a possible trigger.
Scientists have long considered what could set off such massively destructive events, and researchers say they think it's a combination of temperature influence and the geometrical configuration of the magma chamber deep beneath the volcano system. The creation of a malleable ring of rock around the magma chamber allows the pressure to build over tens of thousands of years, creating extensive uplifting in the roof above the magma chamber until geologic faults above the chamber cause it to collapse and trigger a massive eruption.
"You can compare it to cracks forming on the top of baking bread as it expands. As the magma chamber pressurizes at depth, cracks form at the surface to accommodate the doming and expansion. Eventually, the cracks grow in size and propagate downward toward the magma chamber. In the case of very large volcanoes, when the cracks penetrate deep enough, they can rupture the magma chamber wall and trigger roof collapse and eruption."
The eruption of super-volcanoes can trigger planetary climate change by inducing Ice Ages and other impacts. "Short of a meteor impact, these super-eruptions are the worst environmental hazards our planet can face. Huge amounts of material are expelled, devastating the environment and creating a gas cloud that covers the globe for years."
TROPICAL STORMS -
In the Atlantic -
No current tropical storms.
In the Pacific -
-Tropical storm Irwin was located about 150 mi. (245 km) W of Manzanillo, Mexico. There are no coastal watches or warnings in effect.
-Tropical storm Banyan was located approximately 355 nm SSE of Hong Kong, China.