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:  http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt  

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: www.solarcycle24.org and www.wcflunatall.com/propagation.htm   . 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: http://www.solen.info/solar/cyclcomp.html

 

 

 

 

August 2012

Propagation Summary

Solar activity ranged from very low to high levels during late July.  Highest activity occurred on the 19^th 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 20^th.
http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt 

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 20^th 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 12-13^th.
http://www.radio-electronics.com/info/propagation/meteor-scatter-

 

 

June 2011

Propagation Summary

Solar conditions continued to look dismal, although the solar flux did get up to 149 on 21st April.   May marked the start of the Sporadic E season in the Northern Hemisphere so 28MHz and 50MHz will be humming at times. This rather suggests that F layer propagation on 28MHz is non-existent.  Not so - the 706T Amateur Radio DXpedition to Yemen has been romping in to the UK on 10m CW during early May. Not terribly loud, but definitely workable. (Steve Nichols http://g0kya.blogspot.co.uk/ )

Solar Maximum is forecast for May 2013

Solar minimum occurred in December, 2008. The panel decided that the solar cycle 24 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 expected to occur in May, 2013. http://www.swpc.noaa.gov/SolarCycle/ 

Propagation Forecast Up to 16 June

Solar activity is expected to be at very low to low levels with a slight chance for M-class flares through 31 May and again from 14 June through the end of the forecast period.  
Low to moderate levels are expected from 31 May through 13 June.

Geomagnetic field activity is expected to be quiet to active on 22 - 23 May as the arrival of the 18 May Coronal Mass Ejection and a coronal hole high speed stream become active. Quiet to active conditions are also expected on 06 - 09 June as another coronal hole high speed stream moves into an active position. Mostly quiet to unsettled conditions are expected until at least mid June.

April 2012

Propagation Summary.
Predominantly quiet levels are expected to prevail from 21-27 March. On 28 - 31 March, quiet to
active conditions are expected. Quiet conditions are also expected from 01 - 02 April.
From 03 - 04 April, quiet to unsettled conditions are expected, and then quiet levels should prevail from 05 - 12 April, then from 13-14 April, quiet to unsettled conditions should return. A
more detailed forecast can be found at: http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt
The recent solar storms have been in the news during March, and activity will increase during 2012, as we approach the peak of Solar cycle 24. A recent flurry of eruptions on the sun did more than spark pretty auroras around the poles. NASA-funded researchers say the solar storms
of March 8th through 10th dumped enough energy in Earth’s upper atmosphere to power every residence in New York City for two years. “This was the biggest dose of heat we’ve received from a solar storm since 2005,” says Martin Mlynczak of NASA Langley Research Centre.
“It was a big event, and shows how solar activity can directly affect our planet.”
(NASA Science News 22 March 2012)
In terms of propagation, this will usually cause a blackout of HF signals by bringing the ionospheric layers closer to the earth and severely reducing the hop that we normally rely on to receive HF signals at a distance. However, in theory, it could enable you to receive HF signals closer to home which would not normally be receivable. Many of these solar storms are on the far side of the sun but these recent storms were directed towards earth. Depending upon which side of the earth is being affected, propagation could vary considerably, so these are interesting times, as far as propagation is concerned.

April Meteor Showers
Lyrid Meteor Showers are forecast from 19-24 April, peaking on the 21st. Details at: http://www.radio-electronics.com/info/propagation/meteor-scatter-burst-communications/meteors-showers-types.php
Links to all articles at www.jameswelsh.org.uk).
Thanks to Ken Fletcher and Mike Terry for regular updates.

February 2012

Propagation Summary
The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 96 in February of 2013. We are currently about three years into Cycle 24. Increased activity in the last few months has raised the predicted maximum and moved it earlier in 2013. The current predicted size still makes this the smallest sunspot cycle in over 80 years.
The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 96 in February of 2013. We are currently about three years into Cycle 24. Increased activity in the last few months has raised the predicted maximum and moved it earlier in 2013. The current predicted size still makes this the smallest sunspot cycle in over 80 years.

Forecast of Solar and Geomagnetic Activity 25 January - 20 February 2012 Solar activity is expected to be low with M-class flares likely until Regions 1401 and 1402 depart on 28 January. Predominantly quiet levels are expected for the remained of the period. Protons greater than 10 MeV remained above event threshold on 25 - 26 January. A return to background levels is expected for the remainder of the period. The greater than 2 MeV electron flux is expected to be at normal to moderate levels the entire period. The geomagnetic field is was at active to minor storm levels on 25 January as effects from the CME from 23 January waned. Quiet levels returned on 26 and 27 January as a coronal hole high speed stream (CHHSS) became geoeffecitve. A return to quiet levels is expected until 02 - 03 February, with quiet to unsettled levels expected as another CH HSS becomes geoeffective. Predominantly quiet levels are expected from 04-08 February. Another CH HSS is expected to become geoeffective with quiet to unsettled levels expected from 09-10 February. Predominantly quiet levels are expected for the remainder of the period.
http://www.swpc.noaa.gov/ftpdir/weekly/WKHF.txt

Sunspot 1402 produced a major X1.7 Solar Flare on 27 January at 18:37 UTC. An R3 Level Radio Blackout resulted, which led to the fading of HF signals on the sunlit side of Earth. The proton levels are on the rise again and the Moderate S2 level Radiation Storm threshold has been reached. A video of the solar flare is on line at:
http://www.youtube.com/watch?v=3uwojBpajIg&feature=player_embedded

Solar Conditions by Steve Nichols
Good solar conditions continue and we seem to have gone through quite a long period of settled geomagnetic conditions, which has helped no end. The solar flux index has hovered around the 130 mark with no really large fluctuations and as a result we are still seeing the higher bands come to life, notably 10m. But this is really the month for good low-band openings - 160m, 80m an 40m. Tony G3ZRJ reported hearing long delay echoes on 80m at about 2100z on 1st January 2012. These are either signals coming around the world "the wrong way", or aided by magnetospheric ducting, or some other form of propagation that we don't really understand. Whatever, it makes for some interesting effects. http://g0kya.blogspot.com
There is an article about Long Delay echoes (LDE’s) by radio ham Chris Codella at: http://www.w2pa.com/Home/articles/80m-echo-observations

Understanding LF and HF Propagation. (Free Ebook)
In 2008/2009, Alan Melia (G3NYK) and Steve Nichols (G0KYA) wrote a series of features on understanding LF and HF propagation for the RSGB "RadCom" magazine. The book can be downloaded in PDF format at: http://www.infotechcomms.co.uk/Understanding_LF_and_HF_propagation.pdf

Thanks to Mike Terry and Ken Fletcher for regular updates

January 2012

Propagation Summary
The Solar Flux charts have shown a sharp increase in sunspot activity since mid November and by the end of November, average sunspot numbers have actually risen to 95 for the first time since 2003. This has even exceeded the predicted peak forecast for the first quarter of 2013. http://www.swpc.noaa.gov/SolarCycle/
Solar activity was at very low levels on 19 December and increased to low levels from 20–24 December, and finally ending the period (25 December) at moderate levels. Region 1376 was the most active group with frequent B– and C–class flare production until 25 December when new Region 1387 began producing multiple C–class flares and one M–class flare. On 22 December at 0208 UTC, Region 1381 produced a C5 flare associated with weak Types II and IV radio sweeps and a faint CME, determined to be non–geoeffective. Region 1386 produced a C5/Sf flare at 0839 UTC. Region 1376 produced a long–duration C4 flare on the west limb at 1236 UTC associated with a non–Earth–directed CME. On 25 December at 1816 UTC, Region 1387 produced an M4/1N flare that was accompanied by Type II and Type IV radio emissions. A slight proton enhancement was observed on 25 December and achieved a max flux of 3 pfu at 0135 UTC. More information can be found at: http://www.windows2universe.org/sun/solar_activity.html

Solar activity is expected to be at low to moderate levels until 31 December when Region 1387 is forecast to rotate off the disk. Activity is expected to return to low levels with a slight chance for isolated M–class activity for the remainder of the period. No proton events are expected at geosynchronous orbit. The greater than 2 MeV electron flux is expected to be at normal to moderate levels during the period. Geomagnetic field activity is expected to be at active levels from 28–29 December due to CME (Coronal Mass Ejection) arrivals. Diminishing effects from said CMEs will have brought geomagnetic field activity to unsettled levels by 30 December. Mostly quiet conditions were predicted for 31 December, 3–4 and 7–23 January. Activity is expected to be at predominately quiet to unsettled levels 1–2 and 5–6 January due to recurrent coronal hole high speed streams. Although radio blackout warnings have been issued at the end of December, reception conditions are predicted to be good during the quiet periods. ( http://www.swpc.noaa.gov/SolarCycle/ )

2012 Meteor Showers
The next major meteor shower will be the Quadrantid shower, which is expected to peak after midnight on the morning of January 4, 2012. This shower favours northerly latitudes in the Northern Hemisphere. If the peak happens as predicted – at 0700 to 0800 UTC, means eastern North America might be in a good position to watch the 2012 Quadrantid shower. Predicting the peak and the intensity of a meteor shower is always a tricky business, though. No matter where you live, the best time to watch is before dawn on January 4. Best months of the year for meteor scatter are August, October, November, December, and early January. Actually, anytime of the year is good. Sometimes certain dates are just better than others, due to the occurrence of meteor showers. Average peak daily time for night time showers: 0500 to 1200 local time (There are a handful of daytime showers that almost rival the big night time showers and the only way you can be aware of them is to do some research of when they occur.) Best frequencies for meteor scatter: 50MHz to 100 MHz. (The entire 88 to 108MHz band is usable for meteor scatter dxing.) General distance of reception is 600 – 1200 miles. Receiving satisfactory meteor skip signals depends on where you live, what type of equipment you are using, and availability to the peak times of the day ( http://earthsky.org/astronomy–essentials/earthskys–meteor–shower–guide ) Links to these articles can be found at http://www.jameswelsh.org.uk/ .
Thanks to Ken Fletcher and Mike Terry for regular updates during 2011

November 2011

Propagation Summary
The Solar flux has peaked at 140 on September 27-28^th but there is again a downward trend, which will see a drop to 105 by November 7^th. The only noticeable disturbance on propagation conditions was on October 5-6, with the Boulder A index peaking at 18, and the K Index peaking at 5. The general trend for sunspot activity is up, although certainly not to the predicted levels. Daily updates can be found at http://www.wm7d.net/hamradio/solar/27d_forecast.shtml

Historical Solar charts going back to 1950 are available at http://www.solen.info/solar/history/

Implications for Long Term Space Climate Change

“The recent solar minimum was the longest and deepest of the space age, with the lowest average sunspot numbers for nearly a century. The Sun appears to be exiting a grand solar maximum (GSM) of activity which has persisted throughout the space age, and is headed into a significantly quieter period. Indeed, initial observations of solar cycle 24 (SC24) continue to show a relatively low heliospheric magnetic field strength and sunspot number (R), despite the average latitude of sunspots and the inclination of the heliospheric current sheet showing the rise to solar maximum is well underway. We extrapolate the available SC24 observations forward in time by assuming R will continue to follow a similar form to previous cycles, despite the end of the GSM, and predict a very weak cycle 24, with R peaking at ∼65–75 around the middle/end of 2012. Similarly, we estimate the heliospheric magnetic field strength will peak around 6nT. We estimate that average galactic cosmic ray fluxes above 1GV rigidity will be ∼10% higher in SC24 than SC23 and that the probability of a large SEP event during this cycle is 0.8, compared to 0.5 for SC23. Comparison of the SC24 R estimates with previous ends of GSMs inferred from 9300 years of cosmogenic isotope data places the current evolution of the Sun and heliosphere in the lowest 5% of cases, suggesting Maunder Minimum conditions are likely within the next 40 years.” From: http://www.agu.org/pubs/crossref/2011/2011GL049328.shtml

Solar Flare Alerts by Text or Phone

Real time solar activity alerts to your mobile phone or landline phone can be set up online at http://spaceweathertext.com (text) and http://spaceweatherphone.com (voice).

Future Sunspot Cycle Predictions

Sunspot Cycles are Difficult to Accurately Predict. Solar physicists believe the speed of a massive circulating current of hot plasma within the Sun predicts the amplitudes of sunspot Cycles approximately twenty years into the future. In the years prior to 2006 that speed had become lower than ever before. Based on the plasma-speed/future-cycle-amplitude theory, a team led by physicist Mausumi Dikpata of the National Centre for Atmospheric Research predicted Cycle 24 would be intense. NASA solar physicist David Hathaway agreed, but predicted Solar Cycle 25 will be very weak.

VHF Propagation Software

A new VHF propagation gadget is available from SV2AGW. There are two Windows Vista Side Bar gadgets, for Europe and North America. They display Aurora and Sporadic-e propagation using the dxrobot images. George Rossopoulos, SV2AGW has also produced software for AX.25 Packet / APRS, which can be downloaded from his website. http://www.sv2agw.com/downloads/default.htm (Via Mike Terry)

Thanks to Mike Terry and Ken Fletcher for regular updates. The next Propagation report will be in January. Links to these articles and more are available at http://www.jameswelsh.org.uk