Are you telling us that the sea level varies 450 fett from place to place in the world?
What a perfect secular opportunity to reinforce the need for a Magesterium. We are going to need Quix to thoroughly and precisely define the term 'sea level' with respect to some point of reference and then establish the validity of that reference. Then and only then can we begin to assess the validity of his assertion.
Just like discussions of Catholicism and the Catechism we have arrived at the need for a "rubberized dictionary" to establish even a basic vocabulary for further discussion. If Quix asserts (and I'm not saying he does) that sea level is determined from the theoretical surface of a perfect sphere and I am contending that sea level is self determinate based upon the mean of the tides over a finite period of time we will only talk past each other.....just like the Religion Forum.
At least the Catholic Church has driven a stake in the ground as a reference point for the discussions of theology by having fixed "daffynitions".