“This ancient cosmology, which the Israelites shared with their neighbors, included a flat disk-shaped earth with mountains at its ends supporting a multi-layered sky, or domed firmament…the dome had chambers through which the water above it came down as rain,” B. Arnold, Genesis (Cambridge 2009), 41.
Paul Seely assures us that “primitive” people simply judge by appearances. Well, if that’s the case, then this description would go against appearances.
Given the water cycle (evaporation>precipitation>evaporation), the same basic amount of water is constantly recycled (with some variations). So the sea level remains fairly steady. Even if the ice caps melted, the sea could only rise so far. It’s a closed system.
But suppose the source of rain or snow comes from outside. If the “firmament” is like a dam, which releases water in the form of rain or snow, then the earth is like a saucer, bowl or fish tank, and every time it rains, the sea level would rise. There’s no place for the water to go. So it just accumulates.
Assuming that the ancients were simply judging by appearances, wouldn’t this cosmography belie appearances? It doesn’t look like the sea level is steadily rising, does it? It doesn’t look like the dry land is incrementally overtaken by coastal flooding, does it?
I’d add that both Egyptians and Mesopotamians lived on flood plains. Both civilizations were intimately acquainted with flooding. Yet the floodwaters receded. But if you’re living in a cosmic fishbowl, how is that possible? Where is the drain?