Slow Day

Swarm

It has been almost a year since I predicted a major earthquake would hit California in the near future -http://boggythicket.blogspot.com/2011/09/earthquake-prediction.html – and no, it hasn't happened yet.

This week, though, Southern California has experienced an "earthquake swarm” – something I didn’t know existed.

More than 400 earthquakes greater than magnitude 1.0 have been recorded in Imperial County since Saturday evening, said U.S. Geological Survey geophysicist Elizabeth Cochran. The largest were a 5.3 and a 5.5 about midday Sunday.

Scientists say the reason is not fully understood, but there is a clue: Earthquake faults work much differently south of the Salton Sea than they do closer to Los Angeles.

Take, for instance, the San Andreas fault as it runs through Los Angeles County. It’s a fault where, generally speaking, two plates of the Earth’s crust are grinding past each other. The Pacific plate is moving to the northwest, while the North American plate is pushing to the southeast.

South of the Salton Sea, the fault dynamic changes. The Pacific and North American plates start to pull away from each other, Cochran told The Times from her Pasadena office. (That movement is what created the Gulf of California, which separates Baja California from the rest of Mexico.)

So Imperial County is caught between these two types of faults in what is called the Brawley Seismic Zone, which can lead to an earthquake swarm, Cochran said.

The  last major swarm was in 2005, Cochran said, when the largest magnitude was a 5.1. The largest swarm before last weekend's occurred in 1981, when the biggest quake topped out at 5.8. Before that, there were swarms in the 1960s and 1970s.

The Imperial County Board of Supervisors declared the emergency after getting more information about damage. According to the Imperial Valley Press, 19 mobile homes have been red-tagged, several buildings -- including a school auditorium -- have been closed because of damage and water pipes broke. There has been no total damage estimate.

Most of the damage has been cosmetic, and of course a lot of stuff fell off of shelves.

the Great Facebook Experiment

My politics, like my religious beliefs (or lack thereof) are pretty hard to pigeonhole.  I guess I'm closer to being a Libertarian than any other label currently in use, but I’m not a perfect fit.   I’m a fiscal conservative and a human-rights liberal, but there are exceptions in both categories.

I think the spokesmen on both the far left and the far right are a bunch of charlatans and fools, but I do find that even the most outrageous buffoons at either end of the spectrum do occasionally get something right.

Currently, my big complaint is the lack of civility in politics.  I have a Facebook friend who posts dozens of truly offensive articles daily from some of the most blatant of the far left blogs – articles designed to inflame, full of lies and/or carefully edited half-truths. 

I was getting so tired of these tirades that I was considering “unfriending” this person, then today I discovered this option:

 

My Facebook page is Much more pleasant now.

Waterfalls and Rainbows

Came across this photo on the net, and liked it too much not to share.  It was taken somewhere in South America by Ben Steinberger, and features two of my favorite things – waterfalls and rainbows.

Hurricane or Earthquake

It’s been almost a year since I predicted a major quake would hit California soon.  So far, there have been a lot of piddley little tremors – quakes that would be news in Houston, but ignored in LA – but nothing that could be called major. 

Today, it looks like New Orleans will get another hurricane before California gets an earthquake.

Residents in unprotected, low-lying areas outside New Orleans were evacuating Monday as Tropical Storm Isaac threatened to strengthen into a hurricane that could make landfall in or near Louisiana almost seven years to the day that Hurricane Katrina struck.

It's "trying to form an eye-like feature" but it's "still a little bit shy of hurricane status," National Hurricane Center Director Rick Knabb said in a morning update.

At 65 mph, Isaac was just nine miles short of hurricane status and that should happen within the next 24 hours, Knabb added.

The governors of Alabama, Louisiana and Mississippi declared states of emergency as a hurricane warning went into effect for a roughly 300-mile stretch of the Gulf Coast in four states from Louisiana to the Florida Panhandle.

"Tonight is when the conditions will start to go downhill" ahead of landfall Tuesday night, Knabb said.

The National Hurricane Center was no longer forecasting a Category 2 hurricane on landfall, but instead a weaker Category 1. Still, Isaac will probably move slowly inland, possibly dumping as much as 18 inches of rain in places, Knabb said.

"That's going to be the big problem," NBC meteorologist Al Roker said on TODAY. "We're talking about potentially 24 hours of hurricane force winds and heavy rain."

Dead Zone

This year’s severe drought, centered in the Midwest, cut runoff and nutrient loading into the Mississippi and the Gulf of Mexico, resulting in the smallest dead zone in the Gulf in several years.

Texas A&M Oceanography professor Steve DiMarco cruised more than 1,200 miles in the Gulf in mid-August to measure this year’s oxygen-starved area, finding that only about 1,500 square miles affected by hypoxia, mostly near the Mississippi River delta off the coast of Louisiana.

“We had to really hunt to find any hypoxia at all and Texas had none,” DiMarco said. “In all, we found about 1,580 square miles of hypoxia compared to about 3,400 square miles in August 2011. What has happened is that the drought has caused very little fresh-water runoff and nutrient load into the Gulf, and that means a smaller region for marine life to be impacted.”

Hypoxia is when oxygen levels in seawater drop to dangerously low levels, defined as concentrations less than 2 milligrams per liter, and persistent hypoxia can potentially result in fish kills and harm marine life, thereby creating a “dead zone” of life in that particular area.

A trend toward larger dead zones in recent years spurred concern for commercial and sport fisheries, as marine life either dies or moves away from the oxygen-starved waters.

This was the first time in several years that the size of the dead zone stayed below the target of 1,900 miles set by the Gulf of Mexico/Mississippi River Watershed Nutrient Task Force.

The average size of the dead zone between 2005 and 2010 was 6,653 square miles, and the 2011 dead zone, fueled by a record runoff, was larger yet. The task force has been working to reduce nutrient loading.

“Despite fluctuations in the size of the dead zone due to short-term weather events, the fact remains that we have a large and persistent area of severely degraded habitat that is caused by excessive nutrient pollution draining into the Gulf,” said Robert Magnien, Ph.D., director of NOAA’s Center for Sponsored Coastal Ocean Research.

DiMarco said the size of the dead zone off coastal Louisiana has been routinely monitored for about 25 years. Previous research has also shown that nitrogen levels in the Gulf related to human activities have tripled over the past 50 years.

During the past five years, the dead zone has averaged about 5,700 square miles and has reached as high as 9,400 square miles.

The Mississippi is the largest river in the United States, draining 40 percent of the land area of the country, including vast areas of chemically fertilized farmlands. The river accounts for almost 90 percent of the freshwater runoff into the Gulf of Mexico.

“These findings confirm what we found in a trip to the Gulf back in June, and also what other researchers in Louisiana have discovered, so there is general agreement that the dead zone this year is a very, very small one.

“The changes we see year to year are extreme. For example, last year, record flooding of the Mississippi River and westerly winds in the Gulf led to a much larger hypoxic area, particularly earlier in the summer. "

Not My Truck, But…