Empirical Earth · Rotation & How We Measure It

The Coriolis effect — the spin written into storms and gunfire

Storms spin opposite ways by hemisphere, artillery corrects for it, and dropped objects land east — the spin, measured. (The sink demo is a strawman.)

The claim

“The Coriolis effect is a fudge factor, and the draining-sink demo proves it’s fake.”

What is true

A draining sink is not decided by the Earth. Basin shape and how the water was disturbed swamp the effect completely, and anyone who has watched two sinks drain opposite ways in the same house has seen that.

What is measured

The Coriolis deflection scales with sin(latitude). Cyclones turn counter-clockwise north of the equator and clockwise south. Opposite hemispheres, one spinning sphere.

What would show this is wrong

long-range projectiles and cyclones deflecting the same way regardless of hemisphere or latitude.

Sources

  1. Coriolis effect. On a rotating sphere, freely moving objects deflect right (N) / left (S), scaling with sin(latitude): cyclone rotation (Buys-Ballot's law, 1857), long-range ballistics corre link
  2. The Eötvös effect: east-west motion changes measured gravity. Moving eastward adds to Earth’s rotational speed and increases centrifugal force, lowering measured gravity; moving west raises link
  3. Tropical cyclones and the equator. Because the Coriolis force scales with the sine of latitude and vanishes at the equator, tropical cyclones essentially never form within about 5° of it — f link
  4. Ballistic Coriolis drift. Horizontal Coriolis deflection of a small-arms projectile is roughly 2.5–3 in at 1,000 yd near 45° latitude, reversing direction between hemispheres; the vertical E link
  5. Artillery accounts for Earth’s rotation. The US Army field-artillery gunnery manual TC 3-09.81 (successor to FM 6-40) requires firing data to correct for the rotation of the Earth; the “no r link
  6. The railgun is ballistic, not line-of-sight. US Navy program documents describe the electromagnetic railgun’s long-range flight profile as predominantly exo-atmospheric, an indirect ballisti link
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