What is this graph and what does it shows us ?

This graph is one of the major outcome of the IONOSFERA project : it intends to visualise the relationship between Radioamateur's use of the ionosphere (through HF radio links) and the Space Weather conditions. Although, the existence of such relationship has already been documented several times in the past, only in a qualitative manner, reaching now a quantitative knowledge of this relationship is one of the objectives of the IONOSFERA project ...

This graph then collects the number of radio links (in radioamateur language they are called "QSO") achieved daily by a group of 16 Radioamateurs (in radioamateur language they are called "OM") over the world, during a given timeframe chosen to include both quiet and stormy Space Weather conditions. The dataset consists of about 120.000 QSOs over the [6 - 160] meters wavelength range, made independently by the various Radioamateurs, as no exchange of information relating to the scope of this project has been provided to them at the time of QSO data collection.

In the graph, the number of QSOs have been plotted in two ways : (in green) as the total number of QSOs achieved in a given day, summing for that day all the Radioamateurs data and, (in blue) as the total number of QSOs achieved in a given day, divided by the number of Radioamateurs of the group, active on that day. The graph also shows the daily Space Weather conditions : (in dotted orange) the Geomagnetic conditions solely, provided by the product of the Ap and Kp indices and, (in dotted purple) the full Space Weather condition provided by a product of the Solar radio flux F10.7 and the Ap, Kp indices.

The graph clearly shows that peaks of Radioamateur activity through the ionosphere, do not correspond with peaks of Space Weather conditions (and vice-versa). Qualitatively this means, the graph confirms that Radioamateurs easily "work" the ionosphere under quiet Space Weather conditions (the opposite is also true).

And quantitatively ?

Having two parameters : the daily number of QSOs (per OM) and, another parameter defining the (full) Space Weather conditions, which show an opposite behaviour over time, it can be expected that plotted as a function between each other, these two parameters will more or less follow an inverse law ...

The following graphs show this behaviour of the daily number of QSOs achieved per OM, as a function of the parameter "KAF", derived in the framework of IONOSFERA, as indicator of the full Space Weather condition.

On the graph here below, it is impressive to see how "KAF" gives a quantitative limit to the easiness of Radioamateur activity through the ionosphere : when KAF goes over 500 it becomes very improbable to successfully achieve a QSO !

  

 
  The graph plotted directly here above concerns with the same data sample (number of QSOs per OM) but zoomed over the KAF < 500 range. Should we want to make a further classification we could say that :
  • When KAF is lower or in the range of 100, then the use of the ionosphere for Radioamateur purposes is easy
  • When KAF is comprised between 100 and 250, then the use of the ionosphere for Radioamateur purposes is still relatively easy
  • When KAF is over 250, then the use of the ionosphere for Radioamateur purposes becomes difficult

The KAF parameter can then be used operationally to assess the (current) practicability of the ionosphere for Radioamateurs (and other HF radio Operators) 

KAF ? or how is this parameter derived ?

It has been said previously that KAF is a product of the Solar radio flux index F10.7 (which informs us about the Sun activity) with a product of the Ap and Kp indices (informing us about the - Earth - geomagnetic conditions). For the purpose of the analysis presented here above, KAF has been derived as a daily value with the following formula, by use of the daily average of the various Kp (updated every 3-hours) :

KAF = DayAverage(Kp) x Ap x F10.7 / 100

However (and this is done in the "Tools" Section of this site), the current KAF can be estimated in real-time thanks to the availability in SWENET of the current (estimated and/or measured) values of the different Space Weather indices needed for its derivation. 

Other Analyses ...

The IONOSFERA Project will continue the analysis of the received QSOs (about 120.000) in light of the Space Weather. Please visit our website for further updates !

 

  
 

Many thanks to the following Radioamateurs who kindly provided us with their logfiles :

ON4UN, PI4CC, IV3KTY, F5RRS, IH9YMC, I7RIZ, IO3TRK, K3WWP, I4CLK, I2MOV, HB9DHG, IK3ASM, XR2G, ED4MDC, G3PSM and IZ2CHO !

  

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