Experts Predict Weakest Solar Cycle Since 1928
The sun may soon begin moving into a more active period for sunspots, although forecasters predict it will be a fairly mild outbreak.
But even one significant solar storm can wreak havoc on satellites and electrical systems here on Earth.
A weak solar cycle refers to the number of storms, but it only takes one powerful storm to create chaos, according to Doug Biesecker, a scientist with the National Oceanic and Atmospheric Administration’s (NOAA) space weather prediction division.
Indeed, a report by the National Academy of Sciences found that if a storm as strong as one in 1859 took place today, it could cause $1-$2 trillion in damages during the first year, and would require four to ten years to recover.
The 1859 storm shorted out telegraph wires, igniting fires in Europe and North America. It caused such a surge in the Earth’s magnetic field that people read newspapers from the illumination produced by the strong northern lights.
However, there is much more at stake today than mere telegraph lines. The global positioning system, vulnerable electrical grids and satellites that play crucial roles in all forms of communications could all be severely disrupted by a powerful solar storm.Â
An expert panel predicted that a strong blast of solar wind would threaten transportation, national security, financial services and other critical functions. NOAA’s solar prediction center collaborates closely with industry and government agencies to ensure they are prepared to respond if and when such damage might occur, Biesecker told the Associated Press.
Although the most severe storms seem unlikely this cycle, small-scale disruptions to airline flights, electrical service, GPS signals, television, cell phone service and radio are likely.Â
On the positive side, the solar storms often create colorful auroras, known as the northern and southern lights, high in the polar skies.Â
A panel of international experts led by Biesecker said Friday that it expects the forthcoming solar cycle would be the weakest since 1928. The prediction calls for the solar cycle to peak in May 2013 with a monthly average of 90 sunspots per day. If the experts are right, it will be the weakest cycle since a peak of 78 daily sunspots in 1928.
The panel defined solar storms as eruptions of matter and energy that escape from the sun, some of which head toward Earth.
Cycles of more and fewer sunspots typically last several years. The current cycle will be the 24th since counting began during the 1750s.
National Weather Service Director David L. Johnson warned that issuing such long-term outlooks is a work in progress.
"Issuing a cycle prediction of the onset this far in advance lies on the very edge of what we know about the sun," said Johnson in a statement.
The current prediction represents only the third time researchers have tried to make such a forecast. In 1989, a panel predicted the 22nd cycle, which peaked that same year. Scientists predicted cycle 23 in 1996. Both of the previous panels were more accurate in predicting timing rather than intensity, Biesecker said.
The last solar minimum occurred in December, according to researchers. NASA’s W. Dean Pesnell said the forecasts are based on indicators such as the sun’s magnetic field strength at the poles and the reaction of the Earth’s magnetic field to the sun. Both are currently weak, Pesnell said, with only a few sunspots visible in the past two years.
Although scientists were divided in their preliminary forecast for the upcoming cycle issued in 2007, Biesecker said researchers have now reached consensus.
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