Jul 29 2009

Solar Hurricanes: Can We Predict and Protect?

Posted by: Jonathan Marshall

How likely are we to be hit by a geomagnetic storm big enough to take down major power grids across the Northern hemisphere? What kinds of preparations have been made to avoid such an event paralyzing modern industrial civilization?

Some of those questions arose just last week in hearings before the House Homeland Security Committee, whose members took turns blasting the utility industry and public agencies for taking insufficient precautions against natural and man-made threats to the grid.

"Some in government have taken the position that (electromagnetic pulse) attack and  geomagnetic storm disruption are low-probability events," complained William Graham, chairman of the congressionally mandated Commission to Assess the Threat to the United States from Electromagnetic Pulse. "By ignoring large scale, catastrophic . . . vulnerability" the United States needlessly exposes itself to risk, he testified.

Expert opinions about the level of risk vary widely. A grid director at the California Independent System Operator told me that modern forecasting tools and protective equipment to prevent transformer failures mean "the chance of cascading blackouts caused by these solar events is highly unlikely."

On the other hand, an expert at the Edison Electric Institute admitted that "if several dozen large transformers overloaded and blew up, the full recovery time could be months or longer.  I envision an event would be cascading, that is, beginning at a specific point in a northern latitude (say, Quebec) and moving uncontrolled across paths of least resistance."

A spokeswoman for the North American Electric Reliability Corporation, which is tasked with preventing widespread blackouts, said only, "it's certainly an issue that NERC is looking into."

Finally, the National Oceanic and Atmospheric Administration (NOAA), which monitors space weather, states unequivocally: "A single strong blast of solar wind can threaten national security, transportation, financial services and other essential functions."

Let's start with some good news: For now, at least, the sun is acting like a sleeping kitten. Last year, the Sun went 266 days without showing a single sunspot, the quietest year since 1913. Though the sun started breaking out in dark spots again this June, most scientists believe the 11-year sunspot cycle will peak in 2013 at the lowest level since 1928.

The not-so-good news is that the sun could awaken from its slumber at any time and turn into a vicious lion. "As with hurricanes, whether a cycle is active or weak refers to the number of storms, but everyone needs to remember it only takes one powerful storm to cause huge problems," said Doug Biesecker, a scientist at the NOAA's Space Weather Prediction Center in Boulder. "The strongest solar storm on record occurred in 1859 during another below-average cycle."

As we saw yesterday, that 1859 storm, which electrocuted telegraph operators and lit the sky with pyrotechnics as far south as Panama, was stronger even than the 1921 event that a National Research Council study group said could shut down modern life across much of the Northern Hemisphere for a decade.

If the Sun were to get angry, several solar-observing satellites should detect the outbreak of a big geomagnetic storm and relay the information back to scientists on Earth. They include NASA's twin Solar Terrestrial Relations Observatory satellites, launched in 2006, which provide information on the speed, trajectory and shape of so-called coronal mass ejections, multi-billion ton blobs of superhot gas that the sun fires our way at a million miles per hour. These satellites can give up to 24 hours warning of severe solar space weather.

Now the bad news: these satellites serve only a temporary scientific mission, not a long-term early warning system.

NASA also has the aging Advanced Composition Explorer (ACE) satellite a million miles from Earth, which can measure the magnetic field of space weather and thus its likely impact on Earth.

"The problem is, we will only have 15 minutes of warning," NOAA's Biesecker told NEXT100. "That's not a lot of time to react." And if the ACE satellite were to fail, only one other satellite could be moved into place. "That's why NOAA is working hard to get a replacement up there," he said.

Then there's the problem of what to do with the warning. Several grid operators in North America (particularly in the Northeast and New England) have well-codified procedures for dealing with solar magnetic storms. But when the crunch comes, will they really bring down the grid, risking enormous cost and customer inconvenience, just because of an uncertain solar storm prediction? The Quebec power grid crashed in 1989 despite two-day-advance notice of major storming, Biesecker noted.

With so many doomsday scenarios circulating these days, from global flu epidemics to asteroid impacts, it's hard to focus on yet another. But the threat to our way of life from widespread grid failures would be immense. A relatively small investment in improved satellite monitoring and grid protection equipment would be insurance well worth buying.

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