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Monday, March 8

Turkey rocked by 6.0 quake. Is this part of a pattern or just another day at Earth's office?

The quake struck at 4:30 this morning, local time, in Elazig province in eastern Turkey. Six villages were hit hard; the death toll is 57 with about 70 injured. The search for survivors has already been called off so it doesn't seem the toll will rise much higher.

Is there any special significance to the timing of the earthquakes that have struck recently? Faith Mangan reported on March 1 at a Fox News blog that "the earth is constantly on the move: in the last 8 to 30 days, more than 400 earthquakes have been recorded."

What does seem out of the ordinary is that two historic quakes, one in Haiti and the other in Chile, occurred within weeks of each other. There were also record-setting snowstorms in the Atlantic and southern regions of the USA and in Western Europe. These were followed by unseasonable torrential rains in Kenya and neighboring Uganda, which set off a devastating landslide in the latter country, and by unusual storms that generated rare cyclones in Australia and Western Europe. Haiti was also hit by unseasonable rains in February.

Lost in the shuffle of major record-breaking snowstorms this winter was a major earthquake in the northern California town of Eureka (6.5 magnitude, but no serious injuries or damage), which struck on February 10. And there was a surprising earthquake 50 miles northwest of Chicago on February 10 that was three miles deep. The quake struck the day after Snowmageddon 2 -- the historic blizzard in North America, which followed the historic Nor'easter three days prior. Although the quake's magnitude was small (3.8) it was felt as far away as Wisconsin and was only the second notable earthquake in more than 30 years to strike the region.

Then there was the strange weather in the American southwest this winter. From Dr Jeff Masters at the Weather Underground blog, dateline January 22:
The most powerful low pressure system in 140 years of record keeping swept through the Southwest U.S. yesterday, bringing deadly flooding, tornadoes, hail, hurricane force winds, and blizzard conditions. We expect to get powerful winter storms affecting the Southwest U.S. during strong El NiƱo events, but yesterday's storm was truly epic in its size and intensity.

The storm set all-time low pressure records over roughly 10 - 15% of the U.S. -- over southern Oregon and most of California, Nevada, Arizona, and Utah. Old records were broken by a wide margin in many locations, most notably in Los Angeles, where the old record of 29.25" set January 17, 1988, was shattered by .18" (6 mb).

Bakersfield [California] broke its record by .30" (10 mb). The record-setting low spawned an extremely intense cold front that rumbled thought the Southwest, and winds ahead of the cold front reached sustained speeds of hurricane force -- 74 mph --last night at Apache Junction, 40 miles east of Phoenix (Arizona).

Wind gusts as high as 94 mph were recorded in Ajo, Arizona, and a Personal Weather Station in Summerhaven (on top of Mt. Lemmon next to Tucson, Arizona) recorded sustained winds of 67 mph, gusting to 86 mph, before the power failed. Prescott, Arizona sustained winds at 52 mph, gusting to 67 as the cold front passed, and high winds plunged visibility to zero in blowing dust on I-10 connecting Phoenix and Tucson.

The storm spawned one possible tornado in Arizona, which touched down at 8:32 pm MST in Phoenix near Desert Ridge Mall. No damage or injuries were reported. If verified, it would be only the 7th January tornado in Arizona since record keeping began in 1950.[...]
There's more eye-popping information in the same report about that record low-pressure system. But moving along there's been a lot of other record-setting weather this winter, in the United States at least.

From a February 12 report at the Examiner:
There has been a break in the record weather pattern that just brought two blizzards in 5 days to Baltimore, but the pattern itself is not letting up. The southern storm today is dropping snow in Alabama and Georgia. As of 5 pm, Atlanta set a record for the date with 1 inch of snow and more to fall. This storm has prompted Winter Storm Warnings from the Gulf Coast to coastal South Carolina and Georgia. ... Yesterday it passed through Texas and dumped a record 11 inches on Dallas bringing their season total to over 14 inches. The last storm was in December when the city saw its first white Christmas in 83 years. ...

Florida had its hard freeze in January and the coldest Orange Bowl on record. Back in December 2009, Houston received record snow of 0.8 inches ... but up to 6 inches fell farther inland. It was the earliest snow on the record, and the only time in their recorded history that it snowed two years in a row. A reminder of last year's early snow that also set a record in Las Vegas on December 18th. Meanwhile Baltimore has its record setting snowfall for December and the record total month of December with last week's blizzard. Go back to October, and find that record snow at Penn State (in Pennsylvania) cancels tailgating on Homecoming Weekend.[...]
So while perhaps in any given year some part of the world can report unusual or even record-breaking weather or geological events, it does seem we've had a cluster of unusual climate/geologic events within about three months.

The question is whether the cluster means anything more than greater human attention to Earth's housekeeping. I don't think there's any way to objectively answer the question because extensive record-keeping on climate/geological events is not that old. There's just not enough information to draw a conclusion, beyond the general understanding that Earth generates patterns of periodic upheavals.

What we do know with great certainty is that megacities are something new on the planet. This observation begins Joel Achenbach's wonderfully gloomy report for the Washington Post on February 23 titled Under the world's greatest cities, deadly plates -- as in plates that can suddenly slip and cause the ground to swallow a quarter million or so people in a few seconds. The report brings out that the greatest fault resides not in the Earth but in human nature:
... The theory of plate tectonics, largely developed since the 1960s, explains why earthquakes happen in general. The major plates of the earth's crust move constantly, creeping along at about the speed of fingernail growth. They rarely move smoothly past one another but are usually locked in place.

On a strike-slip fault of the type that ruptured in Haiti, strain builds on the fault line for decades or centuries. The fault in Haiti had not ruptured in 240 years. An earthquake is a sudden, stress-relieving event. The fault is said to "break."

Scientists can map faults and estimate how much strain has accumulated since the last quake. What they can't do is say that a given fault will break tomorrow or next year or 10 years from now. Any calculation of earthquake probabilities has a lot of slop in the numbers.

"The problem is, the slop is huge on a human time scale," said Susan Hough, a seismologist with the U.S. Geological Survey. "We're wired to deal with the immediate. We're not geared to plan and stress about things likely to happen in 30 years." ...
Achenbach ends with what I consider an alarming bit of advice from a seismologist named Roger Bilham:
Bilham said he would like to see the United Nations develop a building-inspection program akin to its efforts to look for banned nuclear, biological and chemical weapons.
The United Nations was not even capable of managing something as relatively simple as an oil-for-food program without turning it into a ripoff. And how much inspection does it require, if you know that the vast majority of buildings in a city perched near a fault do not use reinforced concrete?
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