Upsurge in Big Earthquakes Predicted for 2018 (theguardian.com)

hcs_$reboot writes: "Scientists say the number of severe quakes is likely to rise strongly next year because of a periodic slowing of the Earth's rotation," reports the Guardian. "They believe variations in the speed of Earth's rotation could trigger intense seismic activity, particularly in heavily populated tropical regions. Although such fluctuations in rotation are small -- changing the length of the day by a millisecond -- they could still be implicated in the release of vast amounts of underground energy, it is argued."

The theory goes that the slowdown creates a shift in the shape of the Earth's solid iron and nickel "inner core" which, in turn, impacts the liquid outer core on which the tectonic plates that form the Earth's crust rest. The impact is greater on the tectonic plates near some of the Earth's most populous regions along the Equator, home to about a billion people. Scientists from the University of Colorado looked at all earthquakes registering 7 and up on the Richter scale since the turn of the 20th century. In this timeframe, the researchers discovered five periods of significantly greater seismic activity.
The seismic activity follows a five-year period of slowing in the earth's rotatio, and "This link is particularly important because Earth's rotation began one of its periodic slowdowns more than four years ago," according to the article.

"The Earth is offering us a five-year heads-up on future earthquakes," says one of the researchers, adding "The inference is clear. Next year we should see a significant increase in numbers of severe earthquakes."

Comments

Uhmm.... since when do....

[mark-t]

.... we start claiming we can predict earthquakes like we claim to be able to predict the weather or the climate?

Mantle stickiness a factor

[mattr]

This is the kind of prediction you don't really want to be correct about. Would have liked to see some more technical explanation, but from a little googling I see there is a 32 year cycle of slowing which the scientists think might be due to mantle and crust sticking together more, which would also mess up the magnetic field a bit. I had no idea this was a thing. There are various other causes according to wikipedia apparently such as the Indian ocean earthquake which redistributed mass. So I wonder whether there would be any impact from water that melts from arctic ice. People living at the intersection of tectonic plates tend to think about this stuff.
Two links: https://en.wikipedia.org/wiki/...
https://qz.com/1133304/as-eart...

Re:Three Gorges Dam filling up

[rmdingler]

Did you do the calculations for that ?

At least NASA has done those, according to Business Insider.

Effect from the dam filling to the rotation time seems to be just 0,06 microseconds.

We've long suspected that dams could do this, simply because when you shift the weight of the water around the globe, it affects the way the globe spins on its axis. It's the same as how a figure skater can spin faster by holding her arms above her head.

Natural variations in the earth's rotation occur regularly, due to ice melt patterns and such, but it would be ill-advised to discount anthropogenic additions to a poorly understood planet-wide ecosystem. Only a planet dominated by a species that was science-challenged would make that mistake.