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Japanese Earthquake and the Earth's Axis

  1. quotations profile image92
    quotationsposted 7 years ago

    I have heard on the news that the earthquake was so powerful that it changed the earth's rotation and axis by a small degree. I heard a similar story about the Indonesian earthquake.

    Does anyone know:

    1. what is the cumulative effect of both earthquakes on the length of the day and the earth's axis tilt

    2. will the change have any effect on climate? I am thinking that even a small shift in the axis would have a noticeable effect on the polar regions.

    Anyone know?

    1. profile image0
      Baileybearposted 7 years agoin reply to this

      some reports said our day was shortened by a fraction of a second.  Axis moved by around 25 cm & parts Japan's coast moved closer to US by 2.4 m (8 ft)

      1. Rafini profile image90
        Rafiniposted 7 years agoin reply to this

        I would really like to know how they determine these things. hmm

        I heard the day was shortened by 4 minutes (one day or every day?  they didn't say)
        The Axis - I don't remember exactly, but I think it was 4 cm or inches.
        And, I heard Japan moved West by 13 feet.  (not just the coast, the entire country!)

        1. profile image64
          logic,commonsenseposted 7 years agoin reply to this

          GPS is how they determined how far Japan moved.

          1. Rafini profile image90
            Rafiniposted 7 years agoin reply to this

            oh yeah!  I did hear that.  Kinda cool in an exciting yet scary way....

  2. superwags profile image78
    superwagsposted 7 years ago

    It happens because the earth's crust has been forced up by a few feet over a vast area as the Pacific plate has slipped under the Japanese one. My understanding is that it throws out the speed of the earth's spin from the norm because it shifts the distribtion of the Earth's mass. i.e. the mass is further from the centre of the globe.

    I'm aware I haven't done a very good job of explaining that, for a former earth-sciences student!

  3. superwags profile image78
    superwagsposted 7 years ago

    Oh, and incidentally, they measure it using super accurate atomic clocks. It wont be enough for us to notice it!

  4. melpor profile image93
    melporposted 7 years ago

    It just increased the earth's rotation speed by 1 microsecond or 1/1000000 of a second. The the length of the day was decreased by 1/1000000 of a second. I do not think anyone will notice that. This effect will not change anything. The axis was shifted by about a degree and then resets itself because the moon is responsible for keeping the earth's axis at the 23 degrees tilt. The moon also stabilizes the earth's axis so it pretty much keeps it in its current orientation. These effects are extremely small to cause any significant change in our weather system

  5. superwags profile image78
    superwagsposted 7 years ago

    As usual, the BBC has managed to answer this in a more succinct way than me!