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| NASA scientist David Hathaway is a fraud and has no clue what is going on with the Sun. Please Read!
| New Klee Errrr
User ID: 516537
10/3/2008 11:07 AM
Report abusive post | NASA scientist David Hathaway is a fraud and has no clue what is going on with the Sun. Please Read!
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This guy does not have a clue yet he always quoted as an expert.
Two Years Ago
[link to www.newscientist.com]
The next 11-year sunspot cycle will be late but strong according to a new computer prediction. The model used was virtually spot on when applied retrospectively to "forecast" the last eight solar cycles.
"We predict the next cycle will be 30% to 50% stronger than the last cycle," says the model's creator, Mausumi Dikpati, of the National Center for Atmospheric Research's High Altitude Observatory in Boulder, Colorado, US.
The Sun is currently near its minimum activity, at the tail end of a solar cycle, numbered 23. "Onset of the next cycle will be delayed by six to 12 months, to late 2007 or early 2008," Dikpati says. She expects the next peak to hit in 2012.
Sunspots are the dark blotches that temporarily appear on the Sun when magnetic field lines near the star's outer layer push through the surface. View a video of sunspot activity from 1996 to 2005, captured by the SOHO satellite (36MB mpeg file, NASA/ESA). And NASA has more videos, here.
Although each solar cycle – from sunspot minimum to maximum and back again – is roughly 11 years, the periods can vary in length and intensity. The factors governing the cycle have been largely inscrutable.
Dikpati's team tackled the problem by incorporating updated solar dynamical theories along with observations of the Sun dating back to 1880. The result is a model of the Sun with a 20-year "memory" of its magnetic field activity.
Coronal ejections
The model can be tested using past data to "predict" the nature of cycles that have in fact already occurred – and it describes cycles 16 to 23 with better than 97% accuracy. If the model proves to make accurate real predictions, it will finally answer the 150-year-old question of what causes the sunspot cycle, said David Hathaway, a solar astronomer at NASA's Marshall Space Flight Center in Huntsville, Alabama, US, during a press conference on Monday.
And understanding the solar cycle is not just important for science. If the magnetic field lines that pop up to the Sun's surface as a sunspot are twisted and rotate, the spot can yield solar flares and coronal mass ejections, which spew radiation and charged particles in Earth's direction.
Such storms can disrupt the Earth's upper atmosphere, causing numerous problems. So knowing when a cycle is likely to peak could be particularly important during a strong sunspot cycle, says Richard Behnke, director of the US National Science Foundation's Upper Atmospheric Research Section.
"This prediction suggests we're potentially looking at more communications and navigations disruptions, more satellite failures, possible disruptions of electrical grids, blackouts, and more dangerous conditions for astronauts," he says.
Spot the difference
The new results contradict those of a model published in 2005 that found the next cycle could be the weakest in 100 years. Leif Svalgaard, a member of the team behind that model, says the key difference boils down to one simple thing: "How long does the Sun remember its magnetic field?"
Both models are based on the idea that the movement of the Sun's spots is driven by a current of plasma, which pushes the remnants of spots toward the poles, where they sink.
But Svalgaard's model assumes the polar fields left over as one cycle declines then seed the sunspots of the next cycle – i.e. the field strengths from the last cycle directly indicate the strength of the sunspots during the next solar cycle. "We think the Sun forgets its magnetic memory," Svalgaard told New Scientist.
In Dikpati's new model, a sunspot's remnants are carried poleward and down to a depth of about 200,000 kilometres by a plasma "conveyor belt" over a span of about 20 years. They are then carried by a slow flow back toward the equator, and eventually surface as sunspots once again.
This means the strength of the next cycle would depend on the strength of the polar fields from the last three cycles. Cycles 21 and 22 were relatively strong, while cycle 23 was weak, so Dikpati's model predicts the next cycle will be stronger, while Svalgaard's suggests it will be weaker.
Watching and waiting
"It's good the models are diverging," Svalgaard says. "If all models predict the same thing, we don't get wiser." Which model is right will become clear in the first few years of the next solar cycle. "We're all waiting," he says.
Dikpati's model looks excellent based on the tests on previous cycles, but while Hathaway's group at NASA's Marshall Space Flight Center agrees with the prediction of a strong next cycle, they disagree about a delayed onset.
Based on the last 12 cycles, "large cycles usually start early", Hathaway told New Scientist. He expects the cycle to begin in late 2006 or early 2007: "We're anxiously awaiting the appearance of those first spots in the new cycle."
Today
[link to www.nytimes.com]
The Sun has been strangely unblemished this year. On more than 200 days so far this year, no sunspots were spotted. That makes the Sun blanker this year than in any year since 1954, when it was spotless for 241 days.
The Sun goes through a regular 11-year cycle, and it is now emerging from the quietest part of the cycle, or solar minimum. But even for this phase it has been unusually quiet, with little roiling of the magnetic fields that induce sunspots.
“It’s starting with a murmur,” said David H. Hathaway, a solar physicist at NASA’s Marshall Space Flight Center in Huntsville, Ala.
As of Thursday, the 276th day of the year, the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center in Boulder, Colo., had counted 205 days without a sunspot.
In another sign of solar quiescence, scientists reported last month that the solar wind, a rush of charged particles continually spewed from the Sun at a million miles an hour, had diminished to its lowest level in 50 years.
Scientists are not sure why this minimum has been especially minimal, and the episode is even playing into the global warming debate. Some wonder if this could be the start of an extended period of solar indolence that would more than offset the warming effect of human-made carbon dioxide emissions. From the middle of the 17th century to the early 18th, a period known as the Maunder Minimum, sunspots were extremely rare, and the reduced activity coincided with lower temperatures in what is known as the Little Ice Age.
Compared to the Maunder Minimum, the current pace of sunspots “makes it look like we’re having a feast, not a famine,” Dr. Hathaway said.
Scientists expect that sunspot activity will pick up in the coming months, but exactly what will happen next is open to debate. Dr. Hathaway had predicted two years ago, based on the Sun’s behavior near the end of the last cycle, that the maximum this time would be ferocious.
“I’m getting worried about that prediction now,” he said. “Normally, big cycles start early, and by doing that, they cut short the previous cycle. This one hasn’t done that.”
But many of the other competing predictions — more than 50 over all — pointed to a quieter-than-average cycle. “They do kind of go all over the map,” said Douglas Biesecker, a physicist at the Space Weather Prediction Center who led an international panel that reviewed predictions.
The solar wind is another piece of the puzzle. David J. McComas of the Southwest Research Institute in San Antonio and one of the researchers who analyzed data from the Ulysses Sun-watching spacecraft, said that the strength of the solar wind seemed to be in a long-term decline. The pressure exerted by the solar wind particles during the current minimum is about a quarter weaker than during the last solar minimum, Dr. McComas said.
Dr. McComas said scientists were still trying to figure out how all the data fits together.
“There are a number of researchers who predict the next solar cycle,” he said. “There are also a number of investment counselors who predict the future of the stock market.” |
| itdincor 
User ID: 493005
10/3/2008 12:12 PM
 | | Re: NASA scientist David Hathaway is a fraud and has no clue what is going on with the Sun. Please Read! | Quote |
Well, we don't know for if this will cause global cooling or not. At least, not that I've read.
The sun being the source of all energy on Earth, this unusual occurrence will surely have some effect.
So, OP, what is your opinion? Will this cause warming, cooling, or no perceptible effect?
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