Friday, 24 August 2012

September 2012

Propagation Summary

During the second half of August, Solar activity has been at very low to high levels. Two active sunspot regions dominated from 13 August, with multiple C-class solar flares.   Many of these events were associated with discrete radio frequency bursts.  On 17 August, 5 more M class solar flares were observed, but not all were directed towards earth.  Geomagnetic field activity was at predominantly quiet to active levels throughout this period. 

Forecast of Solar and Geomagnetic Activity 20 August - 15 September 2012

A return to predominantly low levels is expected to prevail from 01-15 September. Following an increase to high flux levels on 22-26 August, a return to normal background levels is expected to prevail for the remainder of the period.  Geomagnetic field activity is expected to be at mostly quiet levels, except for 9, 10 and 15 September when the effects of a recurrent coronal hole may cause quite to unsettled conditions. From:  

NZ4O "Daily" Propagation Forecast

Thomas Giella has announced that his NZ4O Medium Frequency, High Frequency and 6 Meter Radio Wave Propagation Forecast is now published on a 'daily' basis. It can be found on line at: and   . Thomas notes that each new edition will be available at around 1300 UTC, but that there will be no daily e-mail notice about its being posted. Just check the websites for the daily updates. (Via Mike Terry).

Solar Cycle comparison Chart
Solar cycle 24 has displayed much less activity than recent cycles.  The monthly smoothed sunspot number could peak between 50 and 70 in 2013. Models based on solar polar magnetic field strength indicate the peak could occur as early as in 2012.  A comparison chart showing solar cycles 21 to 24 can be found at:





August 2012

Propagation Summary

Solar activity ranged from very low to high levels during late July.  Highest activity occurred on the 19th with an M7 flare and a partial halo coronal mass ejection.

Geomagnetic field activity ranged from quiet to major storm levels. Activity on 16 July began at major storm levels and decreased to unsettled levels as the day passed. Quieter to unsettled conditions followed by the 20th.

Forecast of Solar and Geomagnetic Activity

The first half of August will see very low solar activity, but with a slight chance of major flare activity from 30 July to 13 August. The Solar flux is expected to be normal to moderate and on 3-5 august and on 11-15.  Higher levels could prevail on 6010 August.  Geomagnetic field activity is expected to be at quiet to unsettled levels with isolated active periods up to 20th August.

Solar cycle Prediction

The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 60 in the spring of 2013. We are currently over three years into Cycle 24. The current predicted size makes this the smallest sunspot cycle in about 100 years. 

Meteor showers

Perseid Meteor showers are forecast from 30 July-18 August, peaking on 12-13th.