This would be the monumental Solar -Terrestrial Predictions Workshop and its relevant volume (over 630 pages - see cover) completed in the 1980s. The project saw the input from over two hundred solar and space physicists covering every aspect of the problem of solar-terrestrial interactions, including: long, medium and short term solar forecasting, geomagnetic activity and auroral (substorm) forecasts, as well as ionospheric predictions.
I was at the University of the West Indies at the time, and recruited by Dr. Donald F. Neidig of the Air Force Geophysics Laboratory to make a contribution to the specialized area of statistical limitations on flare forecasts, and specifically how Poisson statistics play a role in such forecasting. My paper ‘Limitations of Empirical-Statistical Methods of Solar Flare Prognostication’ appears on pp. 276-284 of the Proceedings and received much attention from the other contributors - since of course it impacted in multiple ways on their work as well.
Sadly, this massive work - the end product of millions of man-hours of intense scientific collaboration and research- is now mostly relegated to the mists of time forgotten. Even googling the header 'Solar Terrestrial Predictions Proceedings- Meudon' brings up nothing of relevance or substance. Like so many things, because it was never digitized, it was as if it never occurred or the work never published (The final book, though dated '1984' - did not actually appear in print format until 1987.)
The
concept of a Poisson-based “delay time” for build up of magnetic free energy,
was first postulated by me in 1984, for application to “SID” (sudden ionospheric
disturbance-generating) flares, with the release attendant on a change in
initial free magnetic energy (E m = B2/2m ) given by[i]:
¶ / ¶ t { òv B2/2m dV} = 1/m òv div[(v X B) X B] dV
- òv {han | Jms |2 }dV
- òv {han | Jms |2 }dV
Since
magnetic gradients and associated scale lengths (ℓB) also will
change in time, there would be scope for accepting a Poisson process
of form P(t) = f(dt,dℓ) which would
embody an energy modulation with some inbuilt variance, with the latter having to be known to determine how much energy might be
released and when. In other words, the differing scale factors inevitably introduced variabilities that were difficult to account for. The Poisson statistics therefore had to be able to take these differing modalities into account.
More recently, Wheatland and Craig (2003)[2]
have argued that the waiting time distribution (WTD) in individual active
regions is consistent with a Poisson process in time, which would conform
to: P(t) = l(t) exp (-lt) where l(t) is the mean rate of flaring or “tick rate”. It must be noted here that a priori l(t) ¹ lm Dt since the latter variability also takes into account
variation in data indices, selection effects arising therefrom (already noted in a paper I had co-authored with Constance Sawyer, in Solar Physics, 1985, 98, 193.) In effect, we had forecast the later work of Wheatland and Craig by at least 18 years.
Being appointed to assist in this huge project - never mind it's no longer on most peoples' radars - remains one of the high points of my scientific career!
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