Propagation Summary
Sunspot numbers have progressively dropped since 2002 with the lowest numbers recorded in 2008. However, since 2009 there has been a upward trend but the Solar Flux progression charts at http://solarcycle24.com/flux.htm still show the sunspot numbers to be consistently lower than predicted. There are more historical charts at: http://wm7d.net/hamradio/solar/historical.shtml
January’s Solar activity is predicted to be on yet another downward trend. The Solar Flux is forecast to drop from 90 to 80 during January. The Boulder A index will stay at 5, except for 4 - 6 and 20 - 21 January. The Boulder A index is likely to remain at a steady 2 for this period.
Global Eruption Rocks the Sun
On August 1, 2010, an entire hemisphere of the sun erupted. Filaments of magnetism snapped and exploded, shock waves raced across the stellar surface, billion-ton clouds of hot gas billowed into space. "The August 1st event really opened our eyes," says Karel Schrijver of Lockheed Martin's Solar and Astrophysics Lab in Palo Alto, CA. "We see that solar storms can be global events, playing out on scales we scarcely imagined before." "The whole-sun approach could lead to breakthroughs in predicting solar activity," commented Rodney Viereck of NOAA's Space Weather Prediction Centre in Boulder, CO. "To predict eruptions we can no longer focus on the magnetic fields of isolated active regions," says Title, "we have to know the surface magnetic field of practically the entire sun." This revelation increases the work load for space weather forecasters, but it also increases the potential accuracy of their forecasts
(NASA Science News. 6 December 2010).
NASA Solar Shield Project
Solar storms don’t just affect radio propagation. Every hundred years or so, a solar storm comes along so potent it fills the skies of Earth with blood-red auroras, makes compass needles point in the wrong direction, and sends electric currents coursing through the planet's topsoil. The most famous such storm, the Carrington Event of 1859, actually shocked telegraph operators and set some of their offices on fire. A 2008 report by the National Academy of Sciences warns that if such a storm occurred today, we could experience widespread power blackouts with permanent damage to many key transformers. Solar Shield is a new and experimental forecasting system for the North American power grid," explains project leader Antti Pulkkinen, a Catholic University of America research associate working at NASA's Goddard Space Flight Centre. "We believe we can zero in on specific transformers and predict which of them are going to be hit hardest by a space weather event."
The troublemaker for power grids is the "GIC" – short for geomagnetically induced current. When a coronal mass ejection (a billion-ton solar storm cloud) hits Earth's magnetic field, the impact causes the field to shake and quiver. These magnetic vibrations induce currents almost everywhere, from Earth's upper atmosphere to the ground beneath our feet. Powerful GICs can overload circuits, trip breakers, and in extreme cases melt the windings of heavy-duty transformers.
This actually happened in Quebec on March 13, 1989, when a geomagnetic storm much less severe than the Carrington Event knocked out power across the entire province for more than nine hours. The storm damaged transformers in Quebec, New Jersey, and Great Britain, and caused more than 200 power anomalies across the USA from the eastern seaboard to the Pacific Northwest. A similar series of storms in October 2003 triggered a regional blackout in southern Sweden and may have damaged transformers in South Africa. Pulkkinen stresses that Solar Shield is experimental and has never been field-tested during a severe geomagnetic storm.
“The more data we can collect from the field, the faster we can test and improve Solar Shield. The next solar maximum is expected around 2013, so it's only a matter of time.“ Full article at: http://science.nasa.gov/science-news/science-at-nasa/2010/26oct_solarshield/
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