How can the surface of one ocean be a different level of another?

Someone said the Panama Canal was difficult to build because the pacific is a different level than the Atlantic. How can this be, if they already touch at other places on the globe?  I’m not talking depth, I’m talking sea level. 

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  • Nancy
    Lv 7
    2 months ago
    Favourite answer

    Because the Pacific side is very, very deep as it is where the continents induct as the tectonic plate upon which the Pacific sits is slowly forced underneath the American continents, creating a giant trench that forms the deepest parts of the ocean worldwide, while the Carribean side is very, very shallow, its extreme shallowness being the reason it gets so warm from the sun and creates so many hurricanes.  The difference in depths results in vastly different sizes of tide, the waves, which are essentially changes in water depth, being much larger on the Pacific side because of how much more water mass there is to be attracted by the Moon's gravity and because wave sizes are twice as high as they appear, going as deep below the water as they go above the water, which when striking the bottom on the shallow Carribean side also has an effect.

    At any rate, what happens is the water level rises much higher at high tide on the Pacific side than on the Carribean side and then sinks to much lower at low tide, which is because of the gravity of the moon pulling up harder on the greater volume of water at high tide and the resultant ebb that causes it to drop that much lower when that gravitational pull moves on because of the spin of the Earth.

     

    • alan P
      Lv 7
      2 months agoReport

      It doesn't really matter whether the sea level at either end of the Panama canal is different or not because the canal goes over a hill using locks.  There is no direct link between the oceans

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  • Anonymous
    2 months ago

    not at all in my opinion

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  • 2 months ago

    several reasons.  1) the force of gravity is not constant in detail because the distribution of mass inside the earth is not uniform (density does not vary constantly with depth or even laterally).  This changes the effective distance between the center of mass of the earth and the "surface", where sea level is an equipotential surface, and thus "sea level" varies slightly (plus or minus about 100 m across the entire surface of the earth); and 2) water takes time to move, and so it "backs up" somewhat in certain places (if there is a large input of fresh water, say like in the Gulf of Mexico from the Mississippi River system), and it is possible for the surface to be slightly higher simply because it hasn't had enough time to reach the equipotential level (water is entering about as fast as it can leave so there is a slight disequilbrium between where gravity would put the water surface and where the water surface actually is).

    And then, of course, there are tidal effects, so even if sea level were actually constant (ignore those other two problems), there would still be a difference in sea level across some 100 km or so of lateral distance.

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  • John
    Lv 7
    2 months ago

    The Moon pulls things around.

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  • 2 months ago

    Depends on how salty it is and it's temperature

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  • alan P
    Lv 7
    2 months ago

    Different parts of the sea are at slightly different levels due to tides, changes in air pressure and the spin of the Earth creating currents. If the sea was perfectly flat then water would not flow from one place to another.  But the Panama canal does not directly link the two oceans.  Ships have to be taken up through a series of locks to a lake that is well above sea level and then down the other side.  Building the canal through dense tropical jungle was very difficult.

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  • 2 months ago

    The average tides at the Pacific end are about 18 feet while on the Atlantic end, its 18 inches. The depth of the water, and the shapes of the bottom and coastline have the greatest effect on that. Since the tides aren't coordinated, the relationship is in constant flux. Incidentally, this disparity means that a sea level canal in Panama would still have to have locks.

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