February 16, 2011

Solar Flares Gonna Get Your Mama

In December I posted an item about the Carrington Event, the Big Solar Flare of 1859, that fried telegraph offices and that would, if repeated, do tremendous damage to our communications and energy infrastructure. Chet Nagle of the Daily Caller has more detail on recent predictions and what it would all mean.
On August 1st and 2nd of last year, an entire hemisphere of the solar disk erupted. The side of the sun facing the earth convulsed in flares, waves of plasma, radio storms and glowing magnetic arcs that blew billions of tons of the sun into space. Astronomers saw solar mayhem so unusual, so violent, that its significance to civilization and life on earth is now being debated by astrophysicists, chemists, engineers, and even clerics. Our alert media did not tell you about it? Then watch the recording of the event by NASA's Solar Dynamics Observatory here.
What you will see if you click on the link is a movie of the sun taken in the extreme ultraviolet part of the spectrum; a clock in the lower left of the screen shows the time and date.

“Wow,”’ you say. “What a light show!” Yes, indeed, and when the solar tsunami reached the earth on August 3rd, it created an aurora borealis display as far south as Iowa. Earth’s magnetic field reverberated from the impact like a big bell hit by a sledgehammer. “Okay,” you say. “I’m sure glad that’s over.” Unfortunately, it is not over. In fact, it is just beginning. Analysts believe a second, greater solar flare is coming — in 2012.

Solar flares appear in eleven-year cycles. The science of why they happen, and how they affect the earth, is complex and replete with words like: coronal mass ejections, auroral electrojet, geomagnetic storm, and solar maximum — or solar max. And scientists, like Mausumi Dikpati of the National Center for Atmospheric Research, believe the next solar max will likely be a “doozy.”

Solar max events are fairly common. One in 1958 blew Northern Lights all the way down to Mexico. A 1972 solar max knocked out telephone lines across Illinois. In 1989, six million people in Canada were blacked out when their power lines were overloaded and fried. That solar max melted huge transformers as far south as New Jersey. In 2005, an x-ray storm left the sun at the speed of light, reached us in eight minutes, and interrupted satellite communications and GPS signals.

The biggest recorded solar max occurred in 1859, the famous Carrington White Light Solar Flare. That “doozy” caused night skies to erupt in auroras so brilliant that newspapers could be read as easily as in daylight. Northern Lights were seen in Cuba, Jamaica, and the Bahamas. Telegraph systems went wild, and sparks shocked telegraph operators and set telegraph paper on fire. Even when telegraphers disconnected batteries, powerful solar max currents in the wires still allowed messages to be transmitted.

In 1859, there were no satellites, of course. There were no cell phones, radio, television, GPS, or Internet. The national power grid did not exist either, and we weren’t dependent on electricity and electronics. Now imagine what would happen if a geomagnetic storm like the 1859 event occurred today, a solar max scientists estimate was driven by the power of 100 billion atomic explosions the size of the Hiroshima bomb!

Somehow the question of whether this will help Obama get reelected, which Nagle subsequently gets into, seems secondary to me. Googling "Mausumi Dikpati of the National Center for Atmospheric Research" yielded the following story from NASA Science News, dated March 10, 2006:
It's official: Solar minimum has arrived. Sunspots have all but vanished. Solar flares are nonexistent. The sun is utterly quiet.

Like the quiet before a storm.

This week researchers announced that a storm is coming--the most intense solar maximum in fifty years. The prediction comes from a team led by Mausumi Dikpati of the National Center for Atmospheric Research (NCAR). "The next sunspot cycle will be 30% to 50% stronger than the previous one," she says. If correct, the years ahead could produce a burst of solar activity second only to the historic Solar Max of 1958.

That was a solar maximum. The Space Age was just beginning: Sputnik was launched in Oct. 1957 and Explorer 1 (the first US satellite) in Jan. 1958. In 1958 you couldn't tell that a solar storm was underway by looking at the bars on your cell phone; cell phones didn't exist. Even so, people knew something big was happening when Northern Lights were sighted three times in Mexico. A similar maximum now would be noticed by its effect on cell phones, GPS, weather satellites and many other modern technologies.

Dikpati's prediction is unprecedented. In nearly-two centuries since the 11-year sunspot cycle was discovered, scientists have struggled to predict the size of future maxima—and failed. Solar maxima can be intense, as in 1958, or barely detectable, as in 1805, obeying no obvious pattern.

The key to the mystery, Dikpati realized years ago, is a conveyor belt on the sun.

We have something similar here on Earth—the Great Ocean Conveyor Belt, popularized in the sci-fi movie The Day After Tomorrow. It is a network of currents that carry water and heat from ocean to ocean--see the diagram below. In the movie, the Conveyor Belt stopped and threw the world's weather into chaos.

The sun's conveyor belt is a current, not of water, but of electrically-conducting gas. It flows in a loop from the sun's equator to the poles and back again. Just as the Great Ocean Conveyor Belt controls weather on Earth, this solar conveyor belt controls weather on the sun. Specifically, it controls the sunspot cycle.
Solar physicist David Hathaway of the National Space Science & Technology Center (NSSTC) explains: "First, remember what sunspots are--tangled knots of magnetism generated by the sun's inner dynamo. A typical sunspot exists for just a few weeks. Then it decays, leaving behind a 'corpse' of weak magnetic fields."

Enter the conveyor belt.

"The top of the conveyor belt skims the surface of the sun, sweeping up the magnetic fields of old, dead sunspots. The 'corpses' are dragged down at the poles to a depth of 200,000 km where the sun's magnetic dynamo can amplify them. Once the corpses (magnetic knots) are reincarnated (amplified), they become buoyant and float back to the surface." Presto—new sunspots!

All this happens with massive slowness. "It takes about 40 years for the belt to complete one loop," says Hathaway. The speed varies "anywhere from a 50-year pace (slow) to a 30-year pace (fast)."

When the belt is turning "fast," it means that lots of magnetic fields are being swept up, and that a future sunspot cycle is going to be intense. This is a basis for forecasting: "The belt was turning fast in 1986-1996," says Hathaway. "Old magnetic fields swept up then should re-appear as big sunspots in 2010-2011."

Like most experts in the field, Hathaway has confidence in the conveyor belt model and agrees with Dikpati that the next solar maximum should be a doozy. But he disagrees with one point. Dikpati's forecast puts Solar Max at 2012. Hathaway believes it will arrive sooner, in 2010 or 2011.

"History shows that big sunspot cycles 'ramp up' faster than small ones," he says. "I expect to see the first sunspots of the next cycle appear in late 2006 or 2007—and Solar Max to be underway by 2010 or 2011."
From NASA's Earth Observatory site comes news that will no doubt improve scientific understanding of the sun's mysteries.
For the first time in history, the world has a full view of the far side of the Sun—and of the entire 360-degree sphere at once, for that matter—thanks to NASA’s Solar Terrestrial Relations Observatory (STEREO). On February 6, 2011, the twin satellites reached opposite sides of the Sun, allowing space weather watchers to detect activity at any point on the sphere and to image eruptions that might be headed toward Earth.
“For the first time ever, we can watch solar activity in its full 3-dimensional glory,” said Angelos Vourlidas, a member of the STEREO science team from the U.S. Naval Research Laboratory. . . (download high definition animation here)

It has been a long journey to a full 360 view of our nearest star. For hundreds of years, ground-based astronomers could only observe the Earth-facing side of the Sun. (Unlike the Moon, the Sun rotates, but we can only see half of the sphere at a time.) With the launch of the Solar and Heliospheric Observatory in 1995, researchers developed methods of helioseismology—studying wave propagation from inside the Sun—to model what was happening on the far side.
It has only been since October 2006, with the launch of STEREO, that scientists have been able to get a true “view” around the earth-visible limb of the Sun. For nearly five years, the two spacecraft slowly moved out in opposite arcs from a common point in the line from Sun to Earth. It took until this month to get to the full separation of 180 degrees.

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