Why would you expect gravity to be constant across the planet if it is an oblate spheroid with non-uniform density and varying composition instead of a homogeneous sphere?
Congratulations, you just disproved the modern science text books....
I said the above because i expected you to know the current model of earth, and know how mass, in the shape of a sphere would display gravity. (basically, the anomalies are cancelled out by the size of the planet. Uniformity is assumed because the planet doesn't have a huge wobble, which it would if one side was heavier than the other. The mathematics works out such that all the mass is considered to be at the center point of the earth)
Furthermore, the gravity is not just a little bit off from being uniform, it is WAY off.
So much so, that there is a scientist who believes that there are micro-blackholes inside the earths crust.
I doubt you have seen any disproofs of flat-earth.
You have probably seen videos which just discard their claims.
But, here is the root problem:
- You can see things over the edge of the horizon.
The US published charts on how far away you could see a light house.
A guy worked out from their height and position, that this was beyond the edge of the horizon.
So, you have to see through the water to see them at that distance.
To drive this point even further, you can see these light houses from even FURTHER on still, clear nights. (so it isn't even a question of it being beyond the horizon)
And now, people are taking infrared photographs of cities WAY over the horizon.
Of course, this could be because light travels along the surface of the earth. (not in a straight line)
How have I disproven science textbooks? What is your evidence for variances being "way off"?
Your dispute is, "a guy said something"? Atmospheric refraction. and mirages are known phenomena. They do not prove a flat earth.
Isn't it interesting that both you and @steampunkkaja went to mirages.
Because there is a big deal of mystery in this phenomena.
And we really do not know how it works. (we do have all kinds of pieces...)
However, the photographs of things over the horizon is becoming a larger and larger body of repeatable evidences.
And the lighthouses.
Are you stating that the reason you can see them from the distance that The US govern-cement printed is because of constant and continual refraction?
Every instance I have seen thus far of something appearing over the horizon at a greater distance than the mathematics would otherwise suggest has exhibited the characteristic distortions of a mirage, or demonstrated a failure in the mathematical model assumed by the "globe debunker." Such mirages do not require the "constant and continual" refraction you seem to believe they demonstrate. All I know is that when I have visited the Great Lakes and the Pacific coast, my personal observations lined up with the predictions of the spheroid earth model.
Doubts about possibility A does not prove possibilities B, C, or D. It doesn't even disprove A. Allow me to attempt an analogy. Let us suppose the entire narrative of 9/11 is a lie. I am willing to consider that possibility. Even so, my doubts regarding the official story do not necessarily prove any given alternative, or disprove that airplanes hit two towers and the Pentagon.
Indeed, light doesn't always travel in a straight line. It bends around massive objects, such as stars (planets, not so much), and is also refracted differentially through the air if there is a temperature gradient. Warmer air is less dense, and therefore has a lower refractive index. Mirages are a particularly interesting example of differential refraction, and while most people associate them with the desert, they are most common (and weirdest) at sea.