Halldór,
for some reason, the
Icelandic activity seems to have much more "bass response"
below 4 kHz on your receiver. I have read that for fairly close lightning
events, an enhanced ELF E-field component can be observed, resulting
from the quasistatic field term. But with the source at about 200 km
from you, this effect should appear only beneath about 240
Hz.
Yes WWLLN is clearly seeing the volcano, so there
must be a significand fraction of cloud-to-ground lightning. However
Blitzortung.org does not seem to pick it up, which is probably because due
to their geographic distribution of detectors, and perhaps also to
higher trigger thresholds.
Best 73,
Markus (DF6NM)
Sent: Saturday, May 21, 2011 11:51
PM
Subject: Re: LF: Volcano eruption on
my VLF-grabber
Hi Halldor & group
Interesting! I
can see the stationary blip on the WWLLN plot over Iceland, I guess that's your
volcano. ...
73 Scott VE7TIL
On 5/21/2011 12:54
PM, Halldór wrote:
Hi all,
Looks like that the new eruption in Iceland is
showing up on my VLF-grabber. Static activity started as soon as the
eruption got through the ice around 19:15 and ash began to fall. Lightnings
are always in the ash cloud. Activity is building up. More ash means more
lightnings. It will be interesting to follow this activity next
days.
73 Halldor
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