Friday 22 May 2009

Propagation June '09

Propagation Forecast
The Boulder 'A' index has remained at a steady 5 and the K index at 2. The first half of June will see 2 fluctuations in these figures. The first one being June 1 – 4 with the A index peaking at 10 and the K index at 4 on June 4th, and again 10th June with the A index peaking at 8 and the K index at 3. The Solar Flux is also starting to vary. June will start out at 70 but this will rise to 72 by Jun 4th and to 74 by the 8th, where it will remain until at least June 13th.

Solar Cycle 24 Prediction Update: Solar Minimum Was December 2008
The Solar Cycle 24 Prediction Panel has reached a consensus decision on the prediction of the next solar cycle (Cycle 24). First, the panel has agreed that solar minimum occurred in December, 2008. This still qualifies as a prediction since the smoothed sunspot number is only valid through September, 2008. The panel has decided that the next solar cycle will be below average in intensity, with a maximum sunspot number of 90. Given the predicted date of solar minimum and the predicted maximum intensity, solar maximum is now expected to occur in May, 2013. Note, this is a consensus opinion, not a unanimous decision. A supermajority of the panel did agree to this prediction. See: http://www.swpc.noaa.gov/SolarCycle/SC24/

This contradicts a report in March 2006 when Dr David Hathaway of the National Space Science and Technology Centre (NSSTC) announced that solar minimum had already arrived and that Solar Maximum would peak in 2010-2011 and would be 30% to 50% stronger than the historic solar maximum of 1958.

In 2006, researchers announced that the most intense storm in 50 years was coming. The prediction came from a team led by Mausamu Dikpati of the National Centre for Atmospheric Research (NCAR). The next sunspot cycle was predicted to be 30% to 50% stronger than the historic solar max of 1958.
From: http://www.nasa.gov/vision/universe/solarsystem/10mar_stormwarning.html

The 1958 Solar Maximum
In 1958 satellites were in their infancy with the Russian Sputnik being launched in October and also Explorer 1, the first US satellite was launched that year. Even so, people knew something was happening when the Northern Lights were sighted 3 times over Mexico. If a similar maximum happened today, it would be noticed by its effect on mobile phones, weather satellites and possibly domestic TV satellites.

The Conveyor Belt Effect
Dr David Hathaway of the NSSTC also has a theory about the ‘Conveyor Belt’ effect which is caused by revolving magnetic fields which carry sunspots away from the sun and back again when they lose their energy.
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. All this happens with massive slowness and a loop can last between 30 and 50 years, so predictability is still variable. Pictures at: http://www.nasa.gov/vision/universe/solarsystem/10mar_stormwarning.html
Historical Solar data Charts Solar charts from 1954 to 2006 from the World Data Centre are available at http://www.solen.info/solar/history/

Thanks to Mike Terry and Ken Fletcher for regular updates. Links to these articles can be found at www.jameswelsh.org.uk

No comments: