AAVSO: American Association of Variable Star Observers
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Solar Cycle 24--Will It Be Unusually Quiet? (Abstract)

Volume 40 number 1 (2012)

Rodney Howe
3343 Riva Ridge Drive, Fort Collins, CO 80526; ahowe@frii.com

Abstract

(Abstract only) For the last forty years or so all the AAVSO (American Association of Variable Star Observers) Very Low Frequency (VLF) Sudden Ionospheric Disturbance (SID) data have been sent to NGDC (National Geophysical Data Center). In this paper these data are put into a database and graphed in hopes of understanding these VLF SID submissions. The graphics show the NGDC accumulated Importance Rating (an index of the duration of solar flares) for all the AAVSO VLF SID submissions over the past forty years. And, if we compare these VLF SID data with the last three solar cycles of sunspot number counts compiled by the Solen group (Jan Alvestad: http://www.solen.info/solar/cyclcomp.html), it seems that the AAVSO VLF SID submissions to NGDC show our accumulated Importance Rating signals lag by 18 to 24 months after the start of each of the last three solar cycles! That puts our VLF radio’s SID IR index measure at a point where it takes at least 100 sunspot counts per month before the VLF SID accumulated IR index even shows a signal through the noise floor of our ionosphere. The VLF observer’s importance rating index is just monitoring the tip of these solar cycles with our VLF radios when compared to the sunspot number count indexes. And if the Solen sunspot predictions are right for Cycle 24, the solar sunspot peak won’t even reach the 70 mark for this next cycle. So, our VLF SID IR index signal submissions may not even be detectable in Cycle 24!