The revelation comes from a new study that peered into the mantle beneath the Pacific Northwest to see what happens when ancient ocean crust from the Pacific Ocean runs headlong into a churning plume of ultra-hot mantle material. Geologically speaking, the Pacific Northwest is a peculiar place. Hot spots usually sit way out on their own in the middle of a tectonic plate (think Hawaii or the Galapagos). Not Yellowstone - it pokes its way to the surface just a few hundred miles from the edge of the North America plate, where a giant trench sends the Juan de Fuca tectonic plate sliding underneath Washington, Oregon, and northern California.
Around 19 million years ago, the Yellowstone hot spot first ascended from deep within the mantle. As it neared the surface, it ran into the subducting Juan de Fuca plate. But the Juan de Fuca plate was itself young at the time (there's a mid-ocean ridge just off the coast of Oregon that forms brand new crust to this day), so it hadn't had the chance fully harden yet. When the crust and hot spot met, the hot mantle plume to found a weakness in the plate - perhaps a pre-existing fracture - and punched a giant hole through it.
The encounter has had several amazing consequences. First, and most obvious, over the last several million years it resurfaced much of northern Nevada, Idaho, and Wyoming in basalt through a series of massive volcanic eruptions. Then there were the tremendous supervolcanic explosions, which coated much of the western U.S. in thick blankets of ash and made the Yellowstone park region what it is today. Second, the rise of the Yellowstone plume also coincided with a large change in the rate at which the crust of the Pacific Ocean dives beneath North America. It's possible that the shattered underlying plate simply didn't pull as much weight anymore, and the subduction zone slowed down. (map)
Peter Drucker
LARGEST QUAKES -
This morning -
None 5.0 or higher.
Yesterday -
9/4/10 -
5.0 PAPUA, INDONESIA
5.0 PAPUA, INDONESIA
5.7 PAPUA, INDONESIA
5.2 SOUTH SANDWICH ISLANDS REGION
5.3 NEAR COAST OF CENTRAL PERU
6.1 TONGA
5.1 SOUTH ISLAND OF NEW ZEALAND
9/3/10 -
5.6 SOUTHERN SUMATRA, INDONESIA
5.1 HOKKAIDO, JAPAN REGION
5.5 SOUTH ISLAND OF NEW ZEALAND
5.7 SOUTH ISLAND OF NEW ZEALAND
7.0 SOUTH ISLAND OF NEW ZEALAND
6.3 ANDREANOF ISLANDS, ALEUTIAN ISLANDS
5.1 NEW IRELAND REGION, P.N.G.
5.1 MID-INDIAN RIDGE
5.0 VANUATU
5.1 NEW BRITAIN REGION, P.N.G.
NEW ZEALAND - A curfew has been imposed in Christchurch, New Zealand after a major earthquake caused extensive damage in the nation's second-largest city. Residents in the city of 372,600 were ordered to stay inside between 7pm and 7am as authorities battle to restore water, power and phone services in the devastated city. About 80 police officers were being sent from Auckland to the South Island to help with law enforcement amid reports of mounting frustration, fighting, serious back logs at petrol stations and traffic jams as people try to leave the city. Residents were evacuated from some areas because of disrupted power and water supplies, and an official state of emergency has been declared.
"The scale of what has happened here is enormous." The mayor said it was miraculous that no one was killed in the quake - measuring 7.0 according to the U.S. Geological Survey - attributing that to the fact it struck about 4.30am when most people were in bed. There were fires reported in the city as power was restored, and the central business district was cordoned off by police amid reports of looting and extensive damage to some older buildings. The damage bill could be as high as NZ$2 billion ($1.6 billion). One man in his 50s is in a serious condition in intensive care at the Christchurch Hospital after a chimney collapsed on him. Another man, also in his 50s, was seriously injured by falling glass. As many as 1000 residents from Christchurch's seaside suburbs were told to prepare for evacuation with flooding expected due to broken water and sewage pipes. Emergency services rescued 10 people from holes which opened up in the ground due to the shaking.
USGS experts said the quake, which struck New Zealand's South Island 45km west of the island's largest city of Christchurch at a depth of 5km, was the result of movement within the crust of the Pacific plate. Scientists have described the earthquake as THE MOST SIGNIFICANT QUAKE SINCE 1931, when a magnitude 7.8 earthquake struck Hawke's Bay. A number of aftershocks were recorded in the area and authorities were concerned about reports that the weather was due to worsen - bringing heavy rain and strong winds to the area in the next 24 to 36 hours.
A series of aftershocks have rattled Christchurch, New Zealand. New Zealand's Civil Defence estimated that more than 500 buildings had been damaged. Local officials say power has been largely restored and tankers will supply water. The country experiences more than 14,000 earthquakes a year, of which only around 20 have a magnitude in excess of 5.0. The last fatal earthquake was in 1968, when a 7.1-magnitude tremor killed three people on the South Island's western coast. During the night following the earthquake, 19 aftershocks were reported. One family in Darfield, near the epicentre of the quake, reported spending the night under their dining table. "The damages are incredibly frightening." Many homeowners faced a cold winter's night and leaking or damaged homes. Hours after the quake, one building in the Christchurch city centre burst into flames, following a suspected gas leak. Daylight showed that the damage was considerably worse than first thought. "There would not be a house, there would not be a family in our city that has not in some way had damage done to their person, to their property. I think it's like an iceberg; there is... below the visible line, significant structural damage." The quake was felt widely across the South Island, including Christchurch and the nearby port city of Timaru. Gale force winds were forecast for Sunday, and authorities have warned that these may affect unstable buildings. "It was absolutely shocking, we're all terrified and scared of what's going to happen next." (map & photos)
Photos sent in of the quake damage
VOLCANOES -
INDONESIA - Sides of Mount Sinabung evacuated once more following new activity from volcano. Scores of people stayed away from their homes near Mount Sinabung for fear of another eruption of the volcano Saturday. A significant eruption Friday was felt 4.9 miles away and sent area residents scurrying back to the evacuation shelters they had only recently left. "This was the strongest eruption as ash plumes reached 3,000 meters (9,842 feet)." Sinabung had been dormant for some four centuries before it awakened last weekend. There have been three eruptions since then and scientists admit they don't know what will happen next.
Alert level raised at another Indonesian volcano: Seulawah Agam - Seulawah Agam on Aceh has been raised to the lowest Alert Status (from no alert) by the Center for Volcanology and Disaster Mitigation due to increased seismicity underneath the volcano. The volcano hasn't erupted since 1839 when it produced a VEI 2 eruption. Beyond that, little is known about Seulawah Agam - it appears that there have been no historic eruptions, but there may have been some minor hydrothermal explosions. A 3-km exclusion zone has been declared around the volcano but no evacuations have been called. This goes with the highest alert status for Sinabung and second highest for Ibu as well. When you combine that with all the volcanoes on the third highest status (Egon, Talang, Karangetang, Batur, Kaba, Anak Krakatau, Semeru, Slamet, Sangeang Api, Rinjani, Soputan and Bromo) you can see the challenge of keeping tabs on all these systems in Indonesia.
TROPICAL STORMS -
-Tropical depression 11E was 52 nmi NW of Tehuantepec, Mexico. [Several models forecast the possibility of a tropical cyclone forming IN THE SOUTHWESTERN GULF OF MEXICO during the next day tor two. It is unclear whether this would come from the remnants of tropcial depression 11-E or a brand new development.]
-Tropical storm EARL was 45 nmi WSW of Halifax, Nova Scotia.
-[Remnants of GASTON could re-develop into a tropical depression at any time. 80% chance of developing into a tropical cycone in the next 48 hours.]
-Tropical storm MALOU was 134 nmi NW of Kadena AB, Okinawa.
EARL weakened to a tropical storm after barrelling ashore in Nova Scotia as a hurricane. "Earl is now a strong tropical storm" buffeting the eastern Canadian province with winds up to 111km/h and heavy rain that has broken tree limbs and knocked down electricity lines, leaving at least 70,000 households without power. There was "conflicting information as to whether Earl was a strong tropical storm or a hurricane at landfall", but it was stated earlier on Saturday that Earl came ashore as a category one hurricane. Winds of 119km/h are considered hurricane strength, and the difference was "easily within meteorological observation errors".
Tropical Storm Earl made landfall in Nova Scotia on Saturday morning hitting the eastern Canadian coast following a rapid acceleration. One man died in the province of Nova Scotia after securing a boat that had slipped its moorings. The storm has brought high winds and heavy rain, toppling trees and power lines through the region and cutting electricity to about 200,000 homes. Earl was moving quickly north-east, with sustained winds of 102km/h. Earl made landfall near the boundary between Shelburne and Queens counties at about 1030 (1330 GMT). Roads throughout Nova Scotia, including in the main city of Halifax, were littered with fallen trees. Power cuts were reported across the province. Earlier, Hurricane Earl was downgraded to a tropical storm as it travelled up the east coast of the US. Strong winds and heavy rain lashed Long Island and Cape Cod as the storm passed by. Officials said the storm caused only minor flooding and power cuts on the US mainland.
Tropical Storm 'Gaston", which formed September 1st in the eastern Atlantic, was declared dissipated on September 2. Originally, very dry air wrapping into its circulation led to its demise. Now, it looks to be gathering for a second wind, according to the National Hurricane Center. The system is moving westward into a moist environment which also has low wind shear values. So the conditions are conducive for re-development. There's a 70% chance of it being re-classified as at least a depression by Sunday. It will retain the original name if this happens. This one is a definite threat to the Caribbean; long-range steering wind projections suggest it could make it into the Gulf as well.
The season has gotten very active in the past two weeks with four named systems (Danielle, Earl, Fiona, and Gaston) forming in the open Atlantic. Danielle formed August 22. Fiona remained a weak tropical storm and dissipated early Saturday. Both Danielle and Earl became major hurricanes but neither ever made landfall, although Earl came rather close.
Malou, the ninth tropical storm this year, is gaining power as it moves northwestward and was expected to bring gusty winds to east China.
HEAVY RAINS, SEVERE STORMS, FLOODING, LANDSLIDES -
AUSTRALIA - Hundreds of homes have been inundated as Victoria faces its WORST FLOODS IN MORE THAN A DECADE. Victoria's northeast was the hardest hit yesterday where the townships of Euroa, Benalla and Myrtleford were issued with emergency evacuation alerts and hundreds of homes are believed to have been affected. It was not clear yet how many homes were flooded or people relocated in these areas. There was still a significant risk of further flooding in those areas. "The rain fall emergency may be over but the flood emergency is yet to reach its peak. There are many communities downstream from those already affected that can still be affected. In those communities there is a strong possibility of homes being isolated and several thousand people being affected."
CHINA - The death toll from rain-triggered landslides that hit a remote village in southwestern China has risen to 24, with another 24 people still missing.
GUATEMALA - A state of emergency has been declared in Guatemala, where days of heavy rain have caused widespread flooding and landslides. At least 18 people have been killed, including at least 10 who died when a bus was engulfed by a mudslide. The rains have undone all the reconstruction work completed since Tropical Storm Agatha, which killed 165 people in May. Days of heavy rains have saturated Guatemala's mountainous terrain, causing hillsides to collapse suddenly and without warning. The worst landslide buried a packed bus as it travelled on the main Inter-American highway, west of the capital Guatemala City. In the western region of Quetzaltenango, a family of four died when their home was buried by a mudslide. At least four other deaths have been reported around the country. More than 100km (65 miles) of the Inter-American highway has been closed to all traffic, and many other roads have been blocked. A bridge that was replaced after being destroyed by Tropical Storm Agatha has again been smashed by floods, cutting the main route to the southwest of the country. Guatemala's national meteorological service forecast that the rains would continue for another 48 hours.
HEAVY SNOW / EXTREME COLD -
The uncharacteristically snowy weather that hit Northern Europe and North America in the winter of 2009/10 was caused by a RARE combination of two separate weather oscillations in the Atlantic and Pacific, claim meteorologists. The harsh winter and heavy snow surprised forecasters, arriving with temperatures at the lowest they’d been for nearly 30 years. Some climate skeptics cited the conditions as evidence against climate change, while other people pointed out that most climate change predictions include an increase in extreme weather events.
But the research claims that neither are correct, and that the FREAK weather was actually caused by an UNUSUAL match-up of a moderately strong El Niño event, and an extremely strongly negative North Atlantic oscillation. Each has a different effect on the weather. An El Niño event tends to push storm systems towards the equator, making the weather in the US and Northern Europe wetter than normal. The North Atlantic Oscillation, on the other hand, doesn’t cause precipitation, it just makes it very cold. When they combine, you get very cold, wet, conditions - snow.
“The NAO was probably AS NEGATIVE AS IT'S EVER BEEN IN THE INTRUMENTAL RECORD WHICH GOES BACK TO THE EARLY 1800s. This was a ONE IN A CENTURY TYPE OF EVENT.”
As for those who raised the spectre of climate change, the researcher is scathing in his dismissal: “Weather will continue to be weather. You have to average over a lot of weather to get the climate trends. There doesn’t seem to be any need to evoke anything else other than that.”
