The sea level at the equator is 23 km higher than if the earth was a perfect sphere, because the earth’s rotation turns it elliptical. I do not know what the 400′ you refer to means.

]]>– Is +400′ of sea-level height accurate at equator vs. sea-level measurement i.e., in the UK?

– If geomagnetic polar shift changes locations of the poles and the equator–would the sea-level height cover lands along new equator and expose lands along the existing equator, at +/- 400′ difference? ]]>

I have not added to this blog for years. Checking now it seems the distance the moon increases is 4 cm not 2.8 cm that I used, and the earth has slowed between 15 and 25 rather than the 17 millionths of a second each year I used. So my calculations could be well out. It is really hard to ever find reliable data, maybe the figures have been revised in recent years.

It seems a leap second is added every approx 1000 days, which indicates a difference between the average current length of a solar day, and a theoretical day of 24 x 60 x 60 seconds where the second is defined by the oscillations of an atomic clock, of about 1 thousandth of a second a day. It is not determined by how the length of the day is currently changing.

I doubt the outer core could possibly rotate in the opposite direction, though it might not necessarily rotate at exactly the same rate as the crust.

I am glad you enjoyed my calculations. I am currently studying electromagnetism, but it is much harder to get my head around than Newtonian mechanics.

]]>Dear William, are you still working on this blog?

I find your calculations most interesting. Two quick questions: is the slowing of the Earth not much faster? I thought we need a leap second every three years or so because the Earth slows by 23 milliseconds per day. The other question is: does not the outer core rotate in a different direction, and therefore take away angular momentum ? ]]>