Quake Lessens Length of Day

[quaoar]

http://www.latimes.com/news/nationworld/nation/la-sci-time8jan08,1,3248444.story?coll=la-headlines-nation

By Usha Lee McFarling, Times Staff Writer

The earthquake that struck beneath the Indian Ocean on Dec. 26 very slightly sped up Earth's rotation, shortening the length of a day by about 2.6 millionths of a second, according to a computer model developed at the Jet Propulsion Laboratory in Pasadena.

Earth's rotational speed changes depending on how mass moves on the planet's surface. Mass can be moved by shifting winds, ocean currents — and earthquakes. When the India tectonic plate lurched beneath the Burma plate, mass shifted toward Earth's center.

"This is analogous to a spinning ice skater bringing her arms closer to her body," said geophysicist Richard Gross, who created the model. "She gets more compact and spins faster."

Because the Global Positioning System readings that measure the planet's rotation are not precise enough, the shift is not likely to be detected, Gross said.

[Trajan]

1. India has been 'crashing' into Asia ....

For hundreds of thousands of years ....

KaBOOM ! .....

[mulethree]

2. I wonder how much the Himalayas grew? n/t

[quaoar]

3. By my calculations

The earthquake has reduced the time until Bush leaves office by 0.0037226 seconds.

[BlueJazz]

4. LOL !...It's not much but I'll take it.

[Viva_La_Revolution]

5. LOL!!!

smarty pants!!

[NYC]

13. Thank you

for the positive slant on that.

[Waistdeep]

6. Wow

We're going to have to have a reverse leap second in about a thousand years.

[GOPFighter]

7. Woo Hoo!

That means my workday will be just over 0.7 millionths of a second shorter - every day!!! Wow.

[Pachamama]

8. Does anyone know if this has ever happened with previous earthquakes in

the time they have been measuring them?

I am absolutely fascinated by this story and wonder what the repercussions of this change are going to be...The world and its eco-system are so fragile in many ways and one altercation, even slight, whether it be changing the temp. in water by just a fraction of degree or introducing a non-native species can set off a chain of events that impact the eco-system in disasterous ways.

I keep asking myself how this could effect anything from our relationship to the gravitational effects of the moon and its effects on tides, to weather patterns to who knows what...

I just think this is possibly a much bigger thing than just a fraction of a "second"....

[daleo]

14. This will occur with any earthquake

Although this was one of the largest recorded, so the effect was larger than usual. An earthquake is a redistribution of mass in the earth's crust, so it changes the earth's moment of inertia ever so slightly, with consequent effects on the earth's rotation (speed and orientation of the axis). The remarkable thing is that we now have instrumentation that can measure these very small effects, that have long been predicted from theory.

[feistydem]

16. That's called the Butterfly Effect...

"Sensitive dependence on initial conditions." --Edward Lorenz, MIT Meteorologist

The flutter of a butterfly's wings in one part of the world can have a transforamive effect on weather conditions on the other side of the world.

Read Chaos by James Glick.

More events are coming...

[Pachamama]

17. Thanks for the tip...I'll pick up the book today....

"Butterfly Effect" - has such a nice name, but I don't think the effects are so nice, eh?

[LosinIt]

9. Well, THAT explains it, I thought the days were shorter

just didn't know why.

[frylock]

10. that's like an unbalanced load of laundry..

something like that could gibber up the whole works.

[Lady Sonelle]

12. Migod! You've Found The Secret of the Second Coming!!

So far the planet's been spinning along the way it has since Christ left it!

Now, when the Earth starts to go "Ka-THUD! Ka-THUD! Ka-THUD!..."
Jeebus HAS to come in and pull out the bedsheets!

Thousands of Xtians suddenly drawn upward (and out of the washerer drum!) like so many vanishing socks!... then He slams the door and starts us whirling again!

YOWWWWW!

Lady Sonelle
"I'm shrrriiiiiinnnnkiiiiinnnnngggggggg Oh, what a world!..."

[TahitiNut]

11. Well, if everyone started running to the east, it'd slow down again.

(Until we stopped.) :shrug: Maybe everyone should just stand up? :dunce:

[DUgosh]

15. In physics it's called resonance and the results can wreak havoc

If five people ran fast back and forth on the top level of the Empire State building it would begin to sway in no time. That continued relentless activity would not make homeland security happy.

[DulceDecorum]

18. The Arctic and the Antarctic

play a huge part in keeping things regular. The rapid melting of the polar caps is suspected of having a destabilizing effect on the rotation of the planet.
Some initial reports from the region indicated that the wobble in the earth's spin had been "corrected" but later reports from the US say otherwise.
http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=125x4046#28992