Sunspot Solar Storm Warning
Researchers predict the imminent arrival of more intense solar storm in the last 50 years.
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March 10, 2006: The news is confirmed: the Solar minimum has arrived. Sunspots have disappeared. There are no solar flares. The sun is quiet.
Like the calm before the storm.
This week a group of researchers announced that a storm is coming-the most intense for at least solar in fifty years. The prediction was made by a team led by Mausumi Dikpati of the National Center for Atmospheric Research (National Center for Atmospheric Research, or NCAR). "The next sunspot cycle will be 30 to 50% more intense than before," she says. If this is correct, in the coming years will see a burst of solar activity second only to the historic Solar Max of 1958.
That was a solar maximum. The space was just beginning:
s atélite Sputnik was launched in October 1957 and Explorer 1 (the first U.S. satellite) in January 1958. In those days you could not tell if a solar storm underway by looking at the bars on a cell phone signal. Even so, people knew something big was happening when Northern Lights were sighted three times in Mexico. Today, a similar solar maximum intensity would have a noticeable effect on cell phones, GPS, weather satellites and many other modern technologies. Right: Auroras intensive on Fairbanks, Alaska, in 1958. [More Information]
Dikpati's prediction is unprecedented. In the nearly two centuries since the discovery of the solar cycle of 11 years, scientists have struggled to predict the maximum intensity of future 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 several years ago, is the Sun Belt Transportation
We have something similar here on Earth: the Great Ocean Conveyor Belt, popularized by the movie The Day After Tomorrow (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 film, the conveyor belt stops and this causes a mess in the earth's climate.
Above: The "Great Ocean Conveyor Belt" of the Earth [More Information]
The Sun's conveyor belt is a current, no water, but gas that conducts electricity. It flows in a loop that goes from Ecuador solar poles and back. As the Great Ocean Conveyor Belt controls the climate of the Earth, the Sun Belt controls the climate of our star. Specifically, it controls the sunspot cycle.
solar physicist David Hathaway of the National Center for Space Science and Technology (National Space Science & Technology Center or NSSTC) explains: "First, remember what sunspots are-tangled knots of magnetism generated by the sun's inner dynamo A typical sunspot lasts only a few weeks. Then decays, leaving behind a 'corpse' of weak magnetic fields.
This is the conveyor belt.
"The top of the conveyor belt skims the surface of the sun, sweeping up the magnetic fields of sunspots. The 'corpses' are dragged toward the poles at a depth of 200,000 km where the sun's magnetic dynamo can amplify them. Then the corpses (magnetic knots) are reincarnated (amplified), they become buoyant and float out to the surface. "Presto-new sunspots!
Right: The" Great Conveyor Belt "of the Sun [larger image]
All this happens with massive slowness. "It takes about 40 years to complete the belt loop," says Hathaway. The speed varies "between a slower pace than 50 years at a rapid pace in 30 years."
When the belt becomes "fast", means that many of the magnetic fields are being swept, and that the future will be intense solar cycle. This is the basis of solar weather predictions: "The belt was accelerating in the cycle from 1986 to 1996," says Hathaway, "the magnetic fields were swept then reappear now as big sunspots in the period from 2010 to 2021 ".
Like most experts in the field, Hathaway has confidence in the conveyor belt model and agrees with Dikpati that the next solar maximum will be very intense. But disagree on one point. Dikpati's prediction puts the solar maximum in 2012. Hathaway believes it will come sooner, perhaps in 2010 or 2011.
"History shows that big sunspot cycles intensify faster than the small spots," he says. "I see the first sunspots of the next cycle in late 2006 or 2007, and incoming solar maximum around 2010 or 2011."
Who is right? Only time will tell. But either way, a storm brewing served by
mireya70
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