Earth ChangesS


Beaker

California Overdue for Massive Quake

The Southern California Earthquake Center (link), an international research collaborative headquartered at the Univ. of Southern California (link), has developed advanced simulation models of how the ground will shake in a magnitude 8.0 earthquake on the southern San Andreas Fault.

Evidence pulled from sediment in three deep trenches suggests the south end of the San Andreas Fault is likely overdue for a massive quake based on historical averages.

This section of the fault has gone perhaps 140 years longer than the average 180 years between quakes, according to the research reported in the February issue of the Bulletin of the Seismological Society of America.


The study also nixes the idea that lake changes in the now-dry region caused past quakes.

However, the findings do not change existing thinking about the threat of a major quake - potentially measuring 7.0 to 8.0 on the Richter scale - for Southern California, including the Los Angeles Basin. Projections of such a quake in recent years led to the nation's largest-ever drill, the Great Southern California ShakeOut, last year. The 2011 ShakeOut is set for Oct. 20. There's even a video projection of the quake's probable route created by the Southern California Earthquake Center. The last earthquake to originate from the area occurred in about 1690.

Radar

Study: Tremors can signal volcano eruption

U.S. and Canadian scientists say volcanoes produce distinctive tremors minutes, days or even weeks before they erupt, making prediction of events possible.

Researchers at Yale University, along with colleagues at the University of British Columbia, said no matter their size or shape, explosive volcanoes produce tremors at similar frequencies, a Yale release said Wednesday.

Prior to most explosive eruptions the volcanoes shake slightly but measurably, and the shaking becomes more dramatic during the eruption itself and is a primary precursor used by vulcanologists for forecasting an eruption.

"Tremor is very mysterious, most notably because it shakes at pretty much the same frequency in almost every explosive volcano, whether it's in Alaska, the Caribbean, New Zealand or Central America," Yale geology professor David Bercovici said.

Snowflake

Winter storm moving into Las Vegas area

High winds today, rain tonight and possibly some snow on Saturday for western foothills of Spring Mountains, forecasters say

Get ready for a mostly cloudy and breezy day, with winds gusting as high as 50 mph in the Las Vegas Valley.

Temperatures will climb to the low 60s today, but the National Weather Service has issued weather advisories and warnings as a winter storm rolls in tonight, bringing wet weather and snow for the weekend.

The wind advisory, which runs from 10 a.m. today until 1 a.m. Saturday, includes Las Vegas, North Las Vegas, Henderson, Boulder City, Summerlin, Nellis, Mountains Edge, Seven Hills and Blue Diamond, the weather service said.

Alarm Clock

Canada: Mount Baker Overdue for Eruption

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© Creative Commons photo, WikimediaMount Baker
Mount Baker is long overdue for an eruption, considering how much "wagging" is going on inside the volcano.
Mark Jellinek, a volcanologist at the University of British Columbia, told the Montreal Gazette that the Washington volcano is showing signs of activity, most notably that it's shaking and vibrating - "wagging," as those in the volcano business say - because of giant columns of magma moving from within.

Jellinek and Yale researcher David Bercovici published research in the journal Nature saying the movement could help predict when the mountain will explode.

Binoculars

Volcano Watch: Things are not always what they seem

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© USGS / B. GaddisAs lava entered the sea in July 2008, littoral explosions sent incandescent lava fragments skyward, building a small littoral cone on the flank of Kilauea
The Hawaiian Islands are home to numerous beautiful landforms. The islands themselves are volcanoes, but these volcanoes are speckled with secondary landforms.

For example, there are numerous cones, or puu, strewn along the coast from the "Road to the Sea" to the Kahuku fault scarp. Are these primary vents? If so, this region would be in Lava Flow Hazard Zone 1 because, by definition, Hazard Zone 1 includes primary vents. Yet this region is not designated Lava Flow Hazard Zone 1.

The "cones" along the coast are littoral cones. Littoral cones are a type of volcanic landform created when lava flows come into contact with the sea. Littoral is a word that means "of or pertaining to the shore of a lake, sea, or ocean."

When seawater and lava interact, the water is converted instantly to steam. This transformation is so abrupt that steam-driven explosions occur. The explosions fragment the lava and propel lava bombs and tephra into the air. The fragments deposited on shore form the cones.

Attention

Philippines: 7 quakes recorded at Taal Volcano

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Taal Volcano
At least seven volcanic quakes were recorded around restive Taal Volcano in Batangas in the last 24 hours, state volcanologists said Friday.

The Philippine Institute of Volcanology and Seismology also noted weak steaming activity even as it said Alert Level 1 stays.

"Alert Level 1 is still enforced over Taal Volcano. This means that a hazardous eruption is not imminent. However, the public is reminded that the Main Crater should be strictly off-limits due to sudden occurrence of steam explosions and accumulation of toxic gases," it said in its Taal update.

Cloud Lightning

Heavy Rain, Winds Bring Flood Threat to U.S. Northeast

Flights to airports in parts of the U.S. Northeast were delayed as much as three hours or more as a storm packing 2 inches (5 centimeters) of rain and wind gusts as high as 60 mph (97 kph) moved across the northern U.S.

Winter storm warnings range from Ohio to Maine, while high wind warnings and watches extend from North Carolina to Massachusetts, according to the National Weather Service (link). Almost 1,100 flights were canceled today, the FlightAware tracking service reported.

A cold front will move through the New York City area about 3 p.m., raising sustained winds to as high as 30 mph with gusts of 60 mph or higher, said Lauren Nash, a weather service meteorologist in Upton, New York.

Cloud Lightning

US: Body of 4th Amish child swept away by flood waters found

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© unknown
Emergency workers in rural Kentucky have found the body of a fourth Amish child killed a buggy flipped in a rain-swollen creek.

The discovery dashed hopes that the 11-year-old girl might have been alive and clinging to a tree or rock through the night.

Arrow Up

The Rise in Sea Level of the Mediterranean is Accelerating

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© IEOIn this image, scientists are collecting samples during the RADMED campaign.
At the end of the 20th century, the rise in sea level of the Mediterranean sea was lower than in the rest of the world due to atmospheric pressure, but since the start of the 21st century the levels of the Mediterranean have regained pace and seem to be accelerating. This has been demonstrated by the updated results from the second edition of the book Cambio Climático en el Mediterráneo Español (Climate Change in the Spanish Mediterranean).

"The sea level in the Mediterranean has risen by between 1 and 1.5 millimetres each year since 1943, but this does not seem set to continue, because it now seems that the speed at which it rises is accelerating", Manuel Vargas Yáñez, main author of the book Cambio Climático en el Mediterráneo Español, and researcher in the Spanish Oceanography Institute (IEO), tells SINC.

The publication, which in its second edition includes, for the first time, climate figures from 1943 to 2008 using a marine observation system which is unique in Spain and pioneering in Europe, confirms that the Mediterranean is becoming warmer. Its salinity is also increasing, and the rise in sea level is accelerating. Since the start of the 21st century the level has already risen by 20 centimetres.

However, "during the last three years which were added to the study (from 2005 to 2008) the rise in temperatures has been slower than at the end of the 20th century, when the sea temperatures rose significantly", points out Vargas Yáñez, who insists on the necessity to study long series of figures to show the impact of climate change in the Mediterranean.

Igloo

US: Unusual Snow Followed by Record Lows

After bringing snow to the Pacific Northwest Wednesday into Thursday, a very cold storm originating from Alaska will continue southward along the coast of California.

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© unknownSetup: Cold storm moves from CA to AZ
The image to the right shows this low-pressure system moving from California into the Southwest Friday through Saturday, bringing snow to unusual places along its path.

Snow will fall to elevations as low as 1,000 feet in the San Francisco Bay Area on Friday. By Friday night into Saturday morning, it's not out of the question that some flakes may fall as low as sea level in the Bay Area. This is all dependent on how much moisture is leftover as the coldest air arrives.

Map: See Bay Area winter storm alerts

According to the National Weather Service, it has not snowed in downtown San Francisco since February of 1976. This gives an idea of the rarity of snow in San Francisco thanks to the marine influence of the Pacific Ocean.