Zoe Doidge
Basically a Goddess
How do you know what sort of physical evidence a global flood would leave behind? Geologists have found evidence (marine fossils) that mountain ranges were once under water.
This is explained at least equally well by plate tectonics. Difference is, we know plate tectonics happened and it continues to do so.
There is plenty of water on earth today to inundate the land masses.
Actually there isn't, at all. 97% of the worlds water is already in the oceans. The remaining water amounts to around 39,000,000,000,000,000 M^3, enough to raise the average global water level by around 76.29M. It'd certainly be a major flood if that happened, but nowhere near on the scale of Noah's Ark.
A sudden, rapid climate change occurred in the past. Large numbers of mammals were killed and then quick frozen.
This is equally well explained by an ice age that doesn't involve a flood at all.