LF: Re: Thunderstorms and LF-Propagation Disturbances

["Alan Melia" <alan.melia@btinternet.com>]

Hi Peter that is very interesting, I have not seen anything quite like that 
before. It is a nice observation. I have heard of the effect, but not seen 
to convincing a plot.
Alan
G3NYK

----- Original Message ----- 
From: "pws" <pws@legal-medicine.de>
To: <rsgb_lf_group@blacksheep.org>
Sent: Wednesday, July 04, 2012 5:50 PM
Subject: LF: Thunderstorms and LF-Propagation Disturbances


> Hi,
>
> I'm observing the strength of HGA22 since some years.
> At late evening of 2012-07-02 strong thunderstorm activity happened
> over E-Germany/Poland/Czech Republic. That's right below the
> reflection area, assuming a 1-hop propagation.
> See: http://www.df3lp.de/misc/hga22/propagation_path.png
>
> It's well known that lightnings may heat the ionosphere from
> below causing disturbances (SIDs). I very often observed
> those phenomena called "early/fast events". But what happened
> last Monday evening looks record-breaking. I never saw such
> chain of ionospheric disturbances.
> See: http://www.df3lp.de/misc/hga22/2012-07-02_thunderstorm.png
>
> Yellow is the raw signal at 10 samples/sec. and blue represents
> a running median of 100 data points. The comb-like structures
> are from the modulation bursts - I'm receiving the "space"
> frequency only. As you can see that's all "signal" and not
> qrn/qrm or local interference. A control receiver running
> ~6km apart confirms the observations.
>
> Peter, df3lp