Earth Axis Tilted Shorten Time by 1.26 Microseconds

Lately I heard a very interesting new. It was about the massive earthquake that struck Chile this year may have shifted Earth's axis and created shorter days according to the scientists at NASA. The change is negligible, but permanent.

We should be having 1.26 microseconds (a microsecond is one-millionth of a second) shorter each day, according to preliminary calculations. The large quake shifts massive amounts of rock and alters the distribution of mass on the planet, which changes the rate at which the planet rotates, where the rotation rate determines the length of a day.



The Earth spins on an axis that is tilted some 23.5° from the vertical. But this position is far from constant – the planet's axis is constantly shifting in response to changes in the distribution of mass around the Earth.

The changing climate has long been known to move Earth's axis. The planet's north pole, for example, is migrating along 79 °W – a line of longitude that runs through Toronto and Panama City – at a rate of about 10cm each year as the Earth rebounds from ice sheets that once weighed down large swaths of North America, Europe, and Asia.

Scientists estimate that the melting of Greenland's ice is already causing Earth's axis to tilt at an annual rate of about 2.6cm and that may increase significantly in the coming years. Now, they calculate that oceans warmed by the rise in greenhouse gases can also cause the Earth to tilt.

Researchers found that as the oceans warm and expand, more water will be pushed up and onto the Earth's shallower ocean shelves. Over the next century, the subtle effect is expected to cause the northern pole of Earth's spin axis to shift by roughly 1.5 cm per year in the direction of Alaska and Hawaii. The effect is relatively small but the motion is strong enough that it needs to be taken into account when interpreting shifts in Earth's axis.

The German Research Centre for Geosciences in Potsdam, says the new work overturns previous ideas. "Up to now, people had believed that height variations [from ocean temperature changes] gave no contribution to polar motion," he told New Scientist. "This is an effect that now has to be considered."

Climate change can also affect the Earth's spin. Previously, the researchers showed that global warming would cause Earth's mass to be redistributed towards higher latitudes. Since that pulls mass closer to the planet's spin axis, it causes the planet to rotate faster. This is similar the the earthquake in Chile.

In summary, by thinking about all the information we gathered, Chile is one of the best example that redistribution of Earth's mass can cause the Earth to rotate faster, which causes shortening of Earth time. Global warming may cause the ice to melt and changes the Earth's mass, and thinking it back, this might lead to another time shift.

Would you want to create a world that we all live right now to change to a degree that beyond recognisable? Lets do our part to preserve Earth as out time has just shorten by 1.26 microseconds from the Chile incident.

All information were cited from various sources such as:
1. CNN website
2. NewScientist.com