In a Bishop Hill discussion about some very dodgy stats methods the mainstream cli-sci community is using, this nice little factoid popped up from commenter ‘dearieme’:
The Jeffreys Prior: fine, but one must be careful not to follow Sir Harold in all his science.
From Wikipedia: Jeffreys was a strong opponent of continental drift. For him, continental drift was “out of the question” because no force even remotely strong enough to move the continents across the Earth’s surface was evident.
Which put me in mind of those solar scientists such as Leif Svalgaard who say that planetary effects on the Sun are “out of the question because no force from the planets even remotely strong enough to affect the Sun is evident”.
Which led me to wonder if consideration of the forces which move continents around might throw up any ideas about the planetary-solar connection. What I discovered on Wikipedia’s plate tectonics page is that the question of what the forces are, and how strong they are relative to each other is very much an open question and a hot subject of ongoing debate.
Alfred Wegener’s idea back in the early 20th century was that continental drift was largely due to tidal forces from Moon and Sun. This was eclipsed by considerations around convection in the mantle, because it was thought that the forces were too small, but has recently enjoyed a renaissance, in combination with consideration of pole-equator compression, coriolis force, and axial wobbles.
So it seems the science of plate tectonics is very much NOT settled, and indeed the Wiki page states quite clearly that “The debate is still open”: Putting more flesh on that admission in this passage:
The sources of plate motion are a matter of intensive research and discussion among earth scientists. One of the main points is that the kinematic pattern of the movements itself should be separated clearly from the possible geodynamic mechanism that is invoked as the driving force of the observed movements, as some patterns may be explained by more than one mechanism. Basically, the driving forces that are advocated at the moment, can be divided in three categories: mantle dynamics related, gravity related (mostly secondary forces), and Earth rotation [tidal and axial wobble] related.
Now let’s contrast this situation with the planetary-Solar theory and mainstream solar physics. We have an observed set of kinematic measurements correlating the motion of the planets and observed solar variations in a variety of metrics such as the incidence of solar flares, the rate of circulation of latitudinal belts, the sunspot number, the meridional flows, the solar wind speed and density. But mainstream solar physicists such as Leif Svalgaard and Cornelis de Jager dismiss possible planetary effects by invoking the argument that the forces are too small.
Perhaps it is time to take a leaf out of the geophysicists book and adopt the policy that “the kinematic pattern of the movements themselves should be separated clearly from the possible solar system dynamic mechanism (or mechanisms) that are invoked as the driving force of the observed movements.
After all, it would be a pity to miss out on the prospect of being able to accurately predict the future evolution of solar activity levels simply because we don’t yet understand the underlying mechanisms. Especially now that important institutions such as NASA are admitting that solar variation has a much larger effect on the variability of the Earth’s climates than has been appreciated hitherto.
I’ll end this short essay with a quote from Sir David Attenborough, who’s not all bad:
I once asked one of my lecturers why he was not talking to us about continental drift and I was told, sneeringly, that if I could I prove there was a force that could move continents, then he might think about it. The idea was moonshine, I was informed.