[crwilson12]

Hello in my area when the tide comes into the bay it creates a tidal bore which travels up a river that emptys into the bay.  It travels over 17 km in less than 45 minutes.  Going by earths curvature it has a massive amount of ground to climb as well as the brooks natural decline.  So how if tides come in so slowly takes over 8 hours here how does this tidal bore gain like 9m of height or more to travel that far up river,  when the whole time the wave stays almost exactly 2 feet tall for the entire 45 minutes

[Iceman]

It's hard to give a full answer without knowing more of the specifics, but as a general thought:

Tides are caused by the earth rotating through the 'bulge' of water pulled by the moon. The magnitude of the tidal changes (up and down) AND the current velocities generated are extremely closely linked to local basin bathymetry. The cross sectional area of the inlets in relation to the volume of water along the coast is a major determining factor.

Examples that are opposing would be the Florida coast, which is straight and in direct connection with deep water vs the Bay of Funday, which is a v-shaped trough that shallows progressively inland.  The constriction in the Bay of Funday is what gives rise to the huge ranges in sea level between high and low tide, and creates strong, fast-moving currents along tributary rivers in the region.

Hope that helps set you on the right path

[Peter Winfield]

Going by earths curvature it has a massive amount of ground to climb as well as the brooks natural decline.

The curvature of the Earth makes no difference to heights above sea level, so the result is the same either way.

The more interesting question is why the tide comes in at all, if there is no gravity to move the water.

[Tumeni]

Hello in my area when the tide comes into the bay it creates a tidal bore which travels up a river that emptys into the bay.  It travels over 17 km in less than 45 minutes.  Going by earths curvature it has a massive amount of ground to climb as well as the brooks natural decline.  So how if tides come in so slowly takes over 8 hours here how does this tidal bore gain like 9m of height or more to travel that far up river,  when the whole time the wave stays almost exactly 2 feet tall for the entire 45 minutes

Would an external wiki be of any help? It seems quite detailed on what causes the effect

https://en.wikipedia.org/wiki/Tidal_bore