Hi Well, specific to Old Faithful ….
They look at the current eruption and rate it for height and duration. Based on that rating, they make a guess about the wait for the next one. Their guess is typically a +/- 10 minute sort of thing. Very much like predicting the weather. https://www.nps.gov/yell/planyourvisit/geyser-activity.htm <https://www.nps.gov/yell/planyourvisit/geyser-activity.htm> Bob > On Apr 1, 2022, at 9:09 AM, Lux, Jim <[email protected]> wrote: > > As I re-read Fleming's "You Only Live Twice" last night, which features a > geyser that is "regulated" by a valve of some sort I was intrigued by this > idea: > > Can one discipline a geyser to an external source? > > a) I assume there's some data somewhere on eruption timing - sure, Old > Faithful is quite regular, sufficiently that they can say "the next eruption > will occur at" and people will gather and watch it. But what's the ADEV? As > a kid in the early 70s, I didn't think to ask this question, and neither > Allan nor Leeson seem to mention it in their papers from 1966. There is a > lot of variation in timing performance of various geysers, though. Old > Faithful *is* regular, and in a place where it's watchable. > > b) Are periodic geysers actually regulatable ?- From the little I know about > how they work, I would think the eruption frequency depends on things like > the water temperature and flow. It's also possible that the valve in > Fleming's novel is purely fictional, because it serves as part of a plot > device at the end (much like closing off the safety valve on a boiler). > > Or, are geysers an example of a chaotic system that is only seemingly regular > in some sense? That is, it's not like a VCO, with a consistent and well > defined relation between the control input and the period. Changing the > control input may change the period in an unpredictable way. Some geysers > stop working if the surrounding hydrology changes. Or is that simply that the > Q of the oscillator is so high that it's easy to "get out of operating > range". That would be like trying to discipline a spurious parasitic > oscillation in an amplifier. > > _______________________________________________ > time-nuts mailing list -- [email protected] -- To unsubscribe send an > email to [email protected] > To unsubscribe, go to and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] -- To unsubscribe send an email to [email protected] To unsubscribe, go to and follow the instructions there.
