-- All the earth means ALL THE EARTH!
You ASSUME Many WRONG things:
-The earth was as it is Now-
Large Mts, Deep oceans, Only 14.7 psi of Atmosphere, No Dinosaurs, Frozen North & South Poles....
- The Ship was too Small
- No way the water on earth could cover everything.
- ONLY the water on Earth NOW was part of the flood.
- Earth was in the same Position it is now, around the Sun (3rd planet, at 1AU from the Sun).
1 Earth was FARTHER away from the Sun.
2 Earth's Atmosphere was 3 - 6x more dense (thick) than it is now (heavier birds could fly).
3 There was much more water in the SKY (you've seen clouds, Imagine clouds with 3 to 6x the Atmosphere - that means Higher up AND thicker.
4 Comets sometimes contain Water-Ice (not always).
5 Comets can be BIG - Rogue Planets become Comets when the enter a solar system and move Toward the Sun.
6 - There is evidence that a Large Comet came by Earth a few times & settled into orbit between Earth and the Sun, Taking most of the Atmosphere from Mars, Dropping much of it into Earth's path then eventually settling into orbit. This additional planet's Gravity pulled us closer to the Sun, but since most of the atmosphere (and 'greenhouse-gasses') was lost we needed More heat
from the Sun. This is ALSO why Humans don't live as long as Before the Flood - we get Too much Radiation now.
Does that Sum it all up?