Confirms Solar Storm Near 2012
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.
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.
Right: Intense auroras over Fairbanks, Alaska,
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.
Above: Earth's "Great Ocean Conveyor Belt."
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.
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."
Right: The sun's "great conveyor belt."
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."
Who's right? Time will tell. Either way, a storm