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Why is the Earth not slowing down?

My assumption is that the slowdown we have observed long-term has been due to friction, both the planet's impact with particles in its path and movement toward gravitational coupling with the Sun's rotation (like the Moon has achieved with the Earth). The first process would make the year longer (or retard its shortening), while the second process would speed the year up (although, as the year shortened, our orbit would move closer to the Sun). These countervailing processes might lead to the departures from trend we see. I don't believe in global warming, but maybe I'm wrong. If the overall temperature of the planet was increasing, would that somehow affect the length of the year?

"My assumption is that the slowdown we have observed long-term has been due to friction, both the planet's impact with particles in its path and movement toward gravitational coupling with the Sun's rotation (like the Moon has achieved with the Earth). The first process would make the year longer (or retard its shortening), while the second process would speed the year up (although, as the year shortened, our orbit would move closer to the Sun). These countervailing processes might lead to the departures from trend we see. I don't believe in global warming, but maybe I'm wrong. If the overall temperature of the planet was increasing, would that somehow affect the length of the year?"

Very interestingly the Sun has many "modes" of "breathing". The primary mode is a very slight radial "breathing" of a few meters in diameter. The interesting thing is that it is precisely 960 minutes long. That is 2/3 of an Earth day, and I have never seen an explanation of why the SUN's internnal modes should give a rat's ass as to the length of an earth day.

There is still a debate about the "speed of gravity". Under classical mechanics (Newtonian) it is easy to show that gravity must have an infinite velocity. Otherwise the Earth and all the planets would be flung from orbit in a few thousand years due to a sort of inverse of the Poynting-Roberson effect. But general relativity resolves the issue, showing that gravity travels at the speed of light, not infinitely fast, and that planets will still stay in their proper orbits.

Interestingly, studies of the overall dynamics of the Solar System with the digital orrery at Caltech show that the solar system as a whole is chaotic and that the orbit of (e.g.) Pluto cannot be predicted with certainty into the far future. The implication is that if one planet's orbit cannot be predicted, then none of them can. However the persistence of the solar system as a stable (yet chaotic) system presents a powerful plausibility argument that things are likely to stay much the same, since they have for the last several billion years...

--Boris

I found this at hypertextbook.com. I think LOD = Length Of Day, but I don't know how it could be measured precisely enough to detect such small changes:

# Solar flares are known to abruptly alter the Earth's rotation. For example, the great flares of 1959 and 1972 brought abrupt changes in the LOD. Both long-term and short-term changes in solar activity alter the Earth's rotation. The 11-year, 22-year and 56-year solar cycles are conspicuous in the LOD data. Long-term (secular) changes were noted at times of fluctuations in solar activity in the past, and the evidence indicates that these changes were very likely abrupt. Observations of the LOD, like so many other geophysical phenomena, reveal the solar-FEM linkage.

I wonder if the weakened solar magnetic field (due to the solar magnetic reversal) has temporarily halted the magnetic braking of the Earth's rotation.