system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can the two oceans be different heights?

The Panama Canal is a series of locks that help raise or lower ships so they can move from one ocean to the other ocean. But the oceans are connected bodies of water! How can they be at different heights? If I had two connected bowls of water, I wouldn't be able to raise the water level of just one bowl, so how do the oceans do that?
gpt
Two reasons.

1) There was a lot of land between the two ocean where the panama canal is right now. So to make the construction easier, they make a lot of dam to create an artificial lake. That lake is about 80 meters higher than the average ocean level, so the lock first make the ships go up to reach the lake, then go down to get to the other Ocean.

2) Ocean are not the same level everywhere even if they are connected. The gravity of our own planet isn't uniform so how much they pull on the water isn't the same everywhere which lead to a different in ocean level from one place to another. This is why you have an average ocean level and not just an ocean level.