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An 11-year epoch of increasingly severe solar storms that could fry power grids, disrupt cell-phone calls, knock satellites back to Earth, endanger astronauts in space, and force commercial airliners to change their routes to protect their radio communications and to avoid deadly solar radiation could begin as soon as this fall, scientists announced Monday.
When the solar cycle reaches its peak in 2012, it will hurl at Earth mammoth solar storms with intense radiation and clouds of high-speed subatomic particles millions of miles across, the scientists said.
A storm of that magnitude could short-circuit a world increasingly dependent on giant utilities and satellite communications networks. Such a storm in 1989 caused power grids to collapse, causing a five-hour blackout in Quebec.
Monday's forecast was announced by scientists from agencies including NASA and the National Science Foundation, based on research centered at the National Center for Atmospheric Research in Colorado.
There is disagreement on exactly when the new cycle will begin -- one key researcher predicted the cycle will start in late 2007 or early 2008, and another said it could begin either late this year or in early 2007. But they did agree that the most severe storms won't begin popping on the solar surface for several years, but when they do, they'll be huge.
The solar storms in the past have knocked out huge power grids and screwed up global electronics and data communications, but "the next sunspot cycle will be 30 to 50 percent stronger than the last one," the scientists said in Monday's statement.
Reaching that 50 percent threshold would make it the most intense solar cycle since the late 1950s and the second worst since the early 1700s, Peter Gilman, one of the researchers, said in a phone interview.
Astronomers will monitor the sun daily in the coming months to see how it's doing. Early warning signs will be the formation of large groups of sunspots, which are clusters of solar magnetic fields that are cooler than the rest of the sun.
"I look (at telescopic images of the sun) almost every day, thinking, 'It could be today,' " said David Hathaway, solar physics team leader at NASA's Marshall Space Flight Center in Alabama. He compared it to "waiting for the first sparrow of spring."
Solar storms can happen at any time during an 11-year solar cycle. However, by far the worst storms are likeliest to occur during the period known as "solar maximum," or solar max for short. The last solar max was in 2001.
The scientists are confident of their forecast for 2012 because they've successfully used a new computer model to "forecast" the past. That is, they used records of old solar cycles to figure out how the sun should have behaved during eight past cycles, as far back as the early 20th century. They "forecast" the sun's past behavior -- "hindcasting," they call it -- "with more than 98 percent accuracy" the scientists said.
"I'm really excited about this (discovery)," said NASA's Hathaway. "It's based on sound physical principles, and it finally answers the 150-year-old question: What causes the sunspot cycle?"
The cycle's victims could include space satellites. The coming storms could heat the upper levels of Earth's atmosphere, causing it to expand and exert drag on low-flying satellites -- perhaps enough drag to tug some of them back to Earth. Solar storms have been blamed for the U.S. Skylab space station's premature fall back to Earth in 1979.
Air travelers could be affected, too. Since the end of the Cold War, to avoid headwinds, airlines have increasingly flown subpolar routes to get between the United States and other Northern Hemisphere continents quickly and cheaply. But during solar storms, they must avoid the poles and fly more southerly routes.
They do so partly in order to avoid having their radio communications disrupted over dangerous polar terrain and partly to avoid exposing passengers -- especially pregnant women -- to the increased radiation, said solar-storm expert Joseph Kunches, chief of the forecast and analysis branch of the U.S. National Oceanic and Atmospheric Administration's Space Environment Center in Boulder, Colo.
The northern and northeastern portions of North America are historically more vulnerable to system outages caused by solar storms than California and most of the Western states, said Gregg Fishman, spokesman for the California Independent System Operator. That's possibly because among other things, he said, there's a higher iron and mineral content in the North and Northeast that conducts the ground current more easily and allows for more of an impact during solar storms.
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The next 11-year solar storm cycle should be significantly stronger than the current one, which may mean big problems for power grids and GPS systems and other satellite-enabled technology, scientists announced today.
The stronger solar storms could start as early as this year or as late as 2008 and should peak around 2012.
"We predict the next solar cycle will be 30 to 50 percent stronger than the last cycle," said Mausumi Dikpati, a solar scientist with the National Center for Atmospheric Research in Boulder, Colorado, yesterday in a telephone briefing with reporters.
The last cycle peaked in 2001.
A new technique enabled the scientists to better predict the severity of the next cycle. The technique, called helioseismology, allows researchers to "see" inside the sun by tracing sound waves reverberating inside the sun—creating a picture of the interior like ultrasound creates a picture of an unborn baby.
"For the first time we can predict the strength of the 11-year solar activity cycle using computer simulations of the sun's physics," Dikpati said.
(See solar-storm images.)
Storms in the Sun
Solar storms are linked to twisted magnetic fields in the sun that suddenly snap and release tremendous amounts of energy. The storms can disrupt satellite communications, cause power outages, and expose astronauts to high amounts of radiation.
Predicting space weather is becoming more important as more people rely on technology that solar storms can disrupt, according to Richard Behnke, director of upper atmosphere research with the National Science Foundation in Arlington, Virginia.
"This prediction of an active solar cycle suggests we are potentially looking at more communication and navigation disruptions, more satellite failures, possible disruption of electric grids and blackouts, more dangerous conditions for astronauts—all these things," Behnke said during the briefing.
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As the world scrambles to prepare for hurricanes and earthquakes of unprecedented strength, some scientists say the sun poses an equal threat, with predictions calling for a 2012 sun storm of immense proportions.
If the idea of a solar storm sounds too much like the stuff of sci-fi, consider this: a single large solar flare has a million times more energy than the largest earthquake, according to Space.com.
The vast space between the Earth and the Sun is filled with electrically-charged particles, radiation, magnetic fields, and electromagnetic energy that could play havoc with Earth in the event of elevated solar output.
The last great solar super storm was 145 years ago. But, this event provides little context given our very recently-adopted dependence on satellite-based technologies.
Last month, experts convened in Colorado during Space Weather Week (April 25-28) to discuss the issues surrounding the approaching 2012 event. If the storm turns out to be at the same scale as the one in 1859, economic disaster would ensue, with immediate costs around the $20 billion mark.
Sten Odenwald of the QSS Corp., based at NASA's Goddard Space Flight Center in Greenbelt predicts that in the 2012 storm will kill only the oldest of the 300 geosynchronous Earth-orbiting (GEO) satellites. However the storm would likely reduce the life of all the other satellites by five to 10 years.
These longer-term problems would add tens of billions of dollars more over the years, Odenwald says. The GEO satellites alone generate about $97 billion US in revenue each year.
A solar superstorm could also:
force about 100 low Earth-orbiting spacecraft to undergo earlier-than-normal reentry
disrupt Global Positioning Systems the world over
force the International Space Station to lose altitude
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