Why does the Panama Canal have canal locks while the Suez Canal doesn’t have any?
In: 2370
Short version:
Panama has many mountains and the ground is full of rock It is very difficult to dig through. So they use a large lake for big parts of the distance. The lake is higher than the ocean becaus it is basically a mountain valley filled with water. You want to keep the lake from draining into the ocean but you still want to move boats from the ocean to the lake and from the lake to the ocean. You build canal locks to do that. You also need to dig less deep into the mountain now because you only need a dig down to the level of the lake and not all the way down to the sea. You have to dog less in hard rock. You are happy and save money.
The area of the Suez Canal area is basically flat and full of sand. There’s also a lake. The lake is (essentially) at the same level as the sea is. You can dig straight ahead without worrying about draining the lake. You don’t need a water lock. Boats can go through the canal faster because they don’t have to wait for the canal locks. Ship Captains are happy because they can get to their destination earlier. You are happy because you can get more boats through per day and earn more money
Maybe [this](https://www.snowtao.com/cruise/Panama/art/panamap.jpg) link will help to illustrate it the Panama side of things.
More information:
I’ve read here a few times that one ocean is much higher than another. The statement that one ocean is at a higher level than another is very misleading and not really true. They might be in reference to the MSL (median sea level). But the MSL is not the actual zero height everywhere because there are (veeeery slight) differences in gravitation depending on where you are on the earth. So if it really depends on what you define as zero height.
Water distributes itself equally according to the gravitational potential of the earth (called the “reference ellipsoid”. There are different versions of it and they are very important today because they are an integral part of GPS and other satellite navigation systems). In this case water will never flow from one ocean to another because the water already had millions of years to get to a state of equilibrium after a change.
For example before the straight of Gibraltar opened up the Mediterranean was not what it is today until one day it broke open and a ridiculous amount of water flowed into what is now the Mediterranean.
But after some time the water settles and there is no more water flowing and the new sea is at equilibrium with the gravitational potential. So even if you dig a canal (like the suez canal) there won’t be any water flowing because the red sea and the Mediterranean are already connected through the Atlantic and indian ocean. They are all at the same level relative to the gravitational potential, the “reference ellipsoid”.
People got this wrong for quite a long time. Even the french, during napoleon’s campaign in Egypt wanted to dig the Suez Canal but were actually worried of different heights of the the red sea and the Mediterranean. And some of his best scientists and engineers said that it is too dangerous to do so. So they didn’t. Back then a (now exceptionally famous) scientist called Joseph Fourier already told them that such a thing would never happen according to gravitational potential theory. They dismissed him. Later they proved he was right and dug canal anyways.
Now why is there still a flow through such canals !? Because the oceans are not at rest and the moon and the rotation of the earth and the moon around a common center of gravity and the sun all create tides. And because water sloshing around has it easier sloshing through a big space like the Atlantic compared to a small space like the Suez Canal or Gibraltar, the tides that arrive are delayed and flow at different speeds to different places (Imagine moving around in your bath tub. Water flows very easily in through the wide part, but it takes some time to flow past you to the other end). Thats why you temporarily have different heights in different oceans.
But you cannot drain an ocean by connecting it to another ocean.
The only way to achieve a different water level relative to the gravitational potential is by disconnecting a body of water from all the seas and then adding water to it. That is essentially what happens with lakes (such as the aforementioned lake in the Panama Canal). They are basically a large bowl of water sitting higher than sea level.
Thats why canal locks are always used to get to a different height, or protect a canal or lake from tides, or prevent a lake from draining, or prevent the mixing of salt and sweet water or such things.
Latest Answers