Earthquake Makes Shorter Days

The massive earthquake that struck Chile on 2/27/10 may have shifted the Earth’s axis and created shorter days, scientists at NASA say.

The change is negligible, but permanent: Each day should be 1.26 microseconds shorter, according to preliminary calculations. A microsecond is one-millionth of a second. A large quake shifts massive amounts of rock and alters the distribution of mass on the planet. When that distribution changes, it changes the rate at which the planet rotates. And the rotation rate determines the length of a day.

Richard Gross, a geophysicist at NASA’s Jet Propulsion Laboratory in Pasadena, California, used a computer model to determine how the magnitude 8.8 quake that struck Chile on February 27 may have affected the Earth.

He determined that the quake should have moved the Earth’s figure axis about 3 inches (8 centimeters). The figure axis is one around which the Earth’s mass is balanced. That shift in axis is what may have shortened days.
Such changes aren’t unheard of.

The magnitude 9.1 earthquake in 2004 that generated a killer tsunami in the Indian Ocean shortened the length of days by 6.8 microseconds.

On the other hand, the length of a day also can increase. For example, if the Three Gorges reservoir in China were filled, it would hold 10 trillion gallons (40 cubic kilometers) of water. The shift of mass would lengthen days by 0.06 microsecond, scientists said.

Advertisements

3 thoughts on “Earthquake Makes Shorter Days

  1. @ Taj, well first I don’t perceive the aftermath of natures events a consequence – they are more the effects of causality.

    But to answer your question, the effects will be that at some point the entire “skin” of the planet will move and place continents in different places. In doing so, there will be a huge climatic difference. For example, the US may become the new South pole…

  2. Makes sense. For clarity, I was wondering if the fact that the days are shortened determines the amount or severity of natural disasters, not necessarily if we as humans deserve or have contributed to them.

Please use the comments to demonstrate your own ignorance, unfamiliarity with empirical data, ability to repeat discredited memes, and lack of respect for scientific knowledge. Also, be sure to create straw men and argue against things I have neither said nor even implied. Any irrelevancies you can mention will also be appreciated. Lastly, kindly forgo all civility in your discourse . . . you are, after all, anonymous :)

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s