Saturday, November 8, 2008

History of Cycle 24 Predictions

Nov 8, 2008: New-cycle sunspot 1007 has disappeared over the sun's western limb.

It is informative to review the solar model predictions for cycle 24 sunspots.

NASA May 20, 2003
Hathaway predicts cycle 24 to begin Dec 2006

NASA Oct 2004
"Hathaway and colleague Bob Wilson, both working at NASA's Marshall Space Flight Center, believe they've found a simple way to predict the date of the next solar minimum. "So, using Hathaway and Wilson's simple rule, solar minimum should arrive in late 2006. That's about a year earlier than previously thought. It'll give us a chance to see if our 'spotless sun' method for predicting solar minimum really works.""

September 15, 2005
"Actually, solar minimum, the lowest point of the sun's 11-year activity cycle, isn't due until 2006..... Hathaway is waiting for 2006 when solar minimum finally arrives."

NOAA Jan 6, 2006
The next sunspot minimum is forecast to occur in late 2006 through mid 2007.

March 6, 2006
For almost the entire month of February 2006 the sun was utterly blank. What's going on? NASA solar physicist David Hathaway explains: "Solar minimum has arrived."

NASA March 10, 2006
March 10, 2006: It's official: Solar minimum has arrived.
"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."
"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."
"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.""

March 2006
That forecast is what provoked Dr. Hathaway at NASA's Marshall Space Flight Center to bet Dr. Gilman that solar cycle 24 was going to come on quickly in 2006 because it was going to be so strong - perhaps the strongest solar cycle on record.

NASA August 15, 2006
"We've been waiting for this," says David Hathaway, a solar physicist at the Marshall Space Flight in Huntsville, Alabama. "A backward sunspot is a sign that the next solar cycle is beginning." The next cycle, Solar Cycle 24, should begin "any time now," returning the sun to a stormy state.

NASA Dec 21, 2006
"Dec. 21, 2006: Evidence is mounting: the next solar cycle is going to be a big one."
"Solar cycle 24, due to peak in 2010 or 2011 "looks like its going to be one of the most intense cycles since record-keeping began almost 400 years ago," says solar physicist David Hathaway of the Marshall Space Flight Center. He and colleague Robert Wilson presented this conclusion last week at the American Geophysical Union meeting in San Francisco."

"According to their analysis, the next Solar Maximum should peak around 2010 with a sunspot number of 160 plus or minus 25. This would make it one of the strongest solar cycles of the past fifty years—which is to say, one of the strongest in recorded history."

Dec 14, 2007 NASA

It may not look like much, but "this patch of magnetism could be a sign of the next solar cycle," says solar physicist David Hathaway of the Marshall Space Flight Center. For more than a year, the sun has been experiencing a lull in activity, marking the end of Solar Cycle 23, which peaked with many furious storms in 2000--2003. "Solar minimum is upon us," he says.

NOAA April 25, 2007
"The next 11-year cycle of solar storms will most likely start next March [2008] and peak in late 2011 or mid-2012 – up to a year later than expected – according to a forecast issued today by NOAA’s Space Environment Center in coordination with an international panel of solar experts"

NOAA April 27, 2007

"Expected to start last fall [2007], the delayed onset of Solar Cycle 24 stymied the panel and left them evenly split on whether a weak or strong period of solar storms lies ahead, but neither group predicts a record-breaker."
“The Space Environment Center’s space weather alerts, warnings, and forecasts are a critical component of NOAA’s seamless stewardship of the Earth’s total environment, from the Sun to the sea,” said retired Vice Adm. Conrad C. Lautenbacher, Ph.D., NOAA administrator."
Jan 2008; First sunspot of Cycle 24 - "Hang on to your cell phone, a new solar cycle has just begun."
With the appearance of Sunspot 981 -- a high-latitude, reversed polarity sunspot -- on Friday, January 4, experts at NASA and NOAA said that Cycle 24 is now here.

"This sunspot is like the first robin of spring," said solar physicist Douglas Biesecker of the Space Weather Prediction Center, part of NOAA. "In this case, it's an early omen of solar storms that will gradually increase over the next few years."
"NASA's Hathaway, along with colleague Robert Wilson at a meeting of the American Geophysical Union in San Francisco last month, said that Solar Cycle 24 "looks like it's going to be one of the most intense cycles since record-keeping began almost 400 years ago."

NASA March 28, 2008
"Barely three months after forecasters announced the beginning of new Solar Cycle 24, old Solar Cycle 23 has returned."

NOAA & NASA June 27, 2008
"The panel expects solar minimum to occur in March, 2008. The panel expects the solar cycle to reach a peak sunspot number of 140 in October, 2011 or a peak of 90 in August, 2012."

NASA July 11, 2008

"The sun is behaving normally. So says NASA solar physicist David Hathaway."
"There have been some reports lately that Solar Minimum is lasting longer than it should. That's not true. The ongoing lull in sunspot number is well within historic norms for the solar cycle."
"some observers are questioning the length of the ongoing minimum, now slogging through its 3rd year."

"It does seem like it's taking a long time," allows Hathaway, "but I think we're just forgetting how long a solar minimum can last."

November 7, 2008, NASA
"After two-plus years of few sunspots, even fewer solar flares, and a generally eerie calm, the sun is finally showing signs of life. "I think solar minimum is behind us," says sunspot forecaster David Hathaway of the NASA Marshall Space Flight Center."

"From January to September, the sun produced a total of 22 sunspot groups; 82% of them belonged to old Cycle 23. October added five more; but this time 80% belonged to Cycle 24. The tables have turned. Even with its flurry of sunspots,the October sun was mostly blank, with zero sunspots on 20 of the month's 31 days."

1 comment:

iblog said...

human influence on solar activity -

what causal link? what feedback loop?

interesting idea