Friday, April 25, 2008

Recent History of Sunspots

In an atmospheric science class at CSU in the late 70's the professor provided a fairly convincing discussion that sun spots control human activity and the earths climate. Sunspots are historically correlated with temperature on earth. During the Dalton Minimum, beginning in 1790, the number of sunspots was low, as the earth's climate turned cold for a few decades. I had not heard nor read much on sun spots until recently.

Background
Sunspots are areas of strong magnetic activity, where material wells up from below. The sun goes through a number of cycles, one including 11 year cycles on sunspots. The dark spots are like tops on a soda bottle, and sometimes they erupt and send bubbles of superheated gas called plasma, into space.
Solar storms spew charged particles into space, and when they interact with Earth's protective magnetic field, electrical charges can dip into the lower atmosphere and even to the ground. These can disrupt radio transmissions and sometimes even power transmission.

Solar Cycle 23 peaked in 2001
Solar Cycle 24 is predicted to start about now

Current situation
You can see the current sunspot activity at
SpaceWeather.com
As of today, April 25 - NO SUNSPOTS?

Implications of low activity?
Geophysicist Phil Chapman was the first Australian to become a NASA astronaut and served as mission specialist on the Apollo 14 lunar mission. Chapman has written that the previous time a cycle was delayed like this was during what was called the Dalton Minimum, a particularly cold period that lasted several decades starting in 1790. "Northern winters became ferocious," he says

So far this year, SOHO has detected just three sunspots, including number 992, which appeared on April 23. One was found in January and lasted only two days. Another appeared earlier this month but vanished within 24 hours. There should be more, many more.

Recent Prior Predictions/Observations
Looking back at recent predictions regarding sunspot activity:
Sun.com May 26, 2008

Adding to the tangle of understanding, the new sunspots have a magnetic polarity consistent with Solar Cycle 23 rather than the new cycle, proving yet again that much remains to be learned about the temperature of the sun.
One of the new sunspots, No. 989, kicked up a moderate solar flare Tuesday. NOAA forecasters put the odds at 50-50 for additional moderate flares today.
Sun.com Dec 2007
"New solar cycles always begin with a high-latitude, reversed polarity sunspot," Hathaway explained in a NASA statement.
"Reversed polarity" means a sunspot with opposite magnetic polarity compared to sunspots from the previous solar cycle. "High-latitude" refers to the sun's grid of latitude and longitude. Old cycle spots congregate near the sun's equator. New cycle spots appear higher, around 25 or 30 degrees latitude. The shift is not certain, however. If it's really the start of a new cycle, there ought to be a sunspot associated with the magnetic knot, but there is none. In fact, Hathaway announced a possible beginning to Solar Cycle 24 back in August, 2006.

Sun.com July 2006
Astronomers say the sun has begun its next cycle of activity, part of an 11-year ebb and flow in sunspots and solar flares. Solar activity is near the low point in the cycle now. Few sunspots appear and solar flares are rare. But on July 31, a tiny sunspot appeared and then vanished after a few hours. It was a normal event, except that it was magnetically backward. "We've been waiting for this," said 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 sophisticated models at UCAR in Boulder predicted increase sunspots for cycle 24, beginning in 2007. "The scientists have confidence in the forecast because, in a series of test runs, the newly developed model simulated the strength of the past eight solar cycles with more than 98% accuracy."
UCAR Boulder CO March 6, 2006
The next sunspot cycle will be 30-50% stronger than the last one and begin as much as a year late, according to a breakthrough forecast using a computer model of solar dynamics developed by scientists at the National Center for Atmospheric Research (NCAR). The NCAR team's computer model, known as the Predictive Flux-transport Dynamo Model, draws on research by NCAR scientists. he scientists expect the cycle to begin in late 2007 or early 2008, which is about 6 to 12 months later than a cycle would normally start. Cycle 24 is likely to reach its peak about 2012.


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