Thursday 12 October 2017

Geomagnetic Propagation Enhancement

The past week has seen a period of quiet solar activity ramp up over the past 24 hours to a Kp between 4 and 5.  Despite being close to solar minimum, disturbed days are quite frequent, no doubt helped by coronal holes.

Luckily, I've been running WSPRlite at 50mW for the past few days as well.  This provided a valuable insight into the propagation enhancements that can occur during more active geomagnetic conditions.

Here's how things panned out geomagnetically, courtesy of NOAA's Space Weather Centre:



Here's the plot at 14MHz, where my 50mW is in blue, and my reference, GI8 comparison station is in red:


As you can see, during the preceding few days, conditions were quiet and propagation drops off in the late evening until early morning, even at 200mW (red).

But with the onset of active conditions, the nighttime propagation shows quite strong enhancements, with fairly rapid variability during darkness.

Here's some detail:


With the restoration of quieter conditions later, propagation returned to the normal drop-off in the middle of the night. Here's the plot either side of the disturbance (ignore the accidental inclusion of a distance label!):



So, the next time you see an active geomagnetic forecast, don't think it's all bad news.  It could surprise you with some unexpected DX!

1 comment:

Alex said...

This is very interesting... you should write a paper and forward it to ARRL,TAPR and any other amateur radio magazine!!

Great work;
Alex - VE7DXW