> There ought to be no latitudinal difference to Gloranthan day length.
IIRC, the main driver for day length changes are the curvature of the earth and the eccentricity of the earth's orbit.
If the axis of rotation was perpendicular to the sun, we'd still have longer days on the equator compared to closer to the poles, because (due to curvature of the earth) the sun would be visible for less time the closer you get to the poles.
Because the earth's axis of rotation is tilted, this exagerates the difference, the closer to the poles you get, as one pole tilts toward the sun and the other tilts away. (They're really tilted pretty much the same direction, just that as the earth moves through the orbit around the sun, that tilt results in one end or the other getting more sun.)
That said, even on the equinoxes, the northern and souther lattitudes get less sun than the equator does, due to the curvature of the earth. Yes?
> The fact that each noon has the sun almost vertically above has always
> been one of the stranger facts of Glorantha to me (more so than any
> horizon theories).
>
It occurs to me, that isn't quite correct.
If the sun travels above the nominal equator during the course of the day, then at noon, the sun would be (roughly) above Magasta's whirlpool, yes? On the nominal equator, the sun would move in an arc through the middle of the sky, straight up over your head. 'north' or 'south' of the equator, you'd see the sun travel in an arc. In the north, it would start in the southeast, peak, and set in the southwest. In the south, the reverse. Depending on how fare east or west of the "prime meridian" you were, would effect the shape of the sun's arc in the sky.
This would also tend to shorten your solar day if there are mountains between you and the solar arc. in the north, trolls would tend to live on the north face of mountains, hills, etc, with doors facing northward (and east or west, depending on how far from center they were) to minimize the time light would shine into the entry.
Hmm. Sundial type clocks would theoretically require calibration both north/south and east/west, making them much more complex than earthly ones, which just require calibration for distance north/south of the equator.
On a line roughly half way from the equator to the northern edge of the world, due north of Magasta's pool, a noon sundial shadow would be at 12 o'clock, due north. Halfway from there to the eastern edge of the world, the shadow would point roughly halfway between 12 and 3, and halfway from the pool to the western edge, the noon shadow would point roughly halfway from 12 to 9. On the equator, solar noon shadow would point to either 3 or 9, depending on whether you were east or west.
Sun dials show subjective time, rather than mechanical time. If you divide the day into 12 hours, by dividing the time from sunup to sundown into 12 hours, your hours are longer in summer than in winter. A water clock, sand clock, or burning candle shows mechanical time, in regular, constant increments.
Using some sort of orbital mechanics to explain varying day lenghts vastly complicates things. A simpler explanation is to make it mythic, and the sun simply really DOES take longer or shorter times to travel the same route depending on the season.
(Sorry, three hour drive home in icky blowing snow, and I'm rambling a little.)
Grimmund
--
"A word to the wise ain't necessary - it's the stupid ones that need
the advice." -Bill Cosby
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