Two geophysicists have found evidence that the flow of iron around Earth's core might clue scientists into the next major earthquakes.
"The Earth offers us a five-year heads up on future earthquakes, which is remarkable," suggests one of the researchers, Roger Bilham from the University of Colorado (CU) in Boulder.
Seismologists and geophysicists have already theorized that the Earth's outer core contributes to small fluctuations in the length of the average day. These differences are so small and represent the tiniest slowings to the speed at which the Earth travels.
Bilham and Rebecca Bendick from the University of Montana noted that there's a correlation between the length variations and major magnitude 7 earthquakes over the last 100 years. The two researchers theorize that the molten iron moving around Earth's core could be the cause.
"The correlation they've found is remarkable, and deserves investigation," Peter Molnar from Colorado University, who wasn't involved in the study, said in an interview with Science.
If the research of Bilham and Bendick hold up during peer reviews, then seismologists and other researchers would have one more resource to predict earthquakes. This new measurement could give us as much as five years warning before another major earthquake strikes -- or at the very least, a rising presence of high-powered tremors.
"I've worked on earthquakes triggered by seasonal variation, melting snow," Michael Manga of the University of California, Berkeley, told Science. "[This] correlation is much better than what I'm used to seeing."
Currently, the movement of the iron core is one of a handful of factors affecting the Earth's magnetic field as well as the length of day (LOD). Previous research noted that in the absence of an external force, the angular momentum of the Earth has to be reliant upon the internal forces to be constant. Thus, the core, mantle, crust, tides, atmosphere, and cryosphere all serve as pieces of the larger puzzle on precisely how long each day lasts. A change in one area (like the atmospheric angular momentum or AAM) has to be accounted for in another region (like the earth's core) so to properly maintain the balance.
"The year 2017 marks six years following a deceleration episode that commenced in 2011," write the researchers, "suggesting that the world has now entered a period of enhanced global seismic productivity with a duration of at least five years."
If the research is correct, we're to expect between 17 to 20 heavy earthquakes each year starting in 2018.
The research was initially published in August but is now being presented at recent meetings of the Geological Society of America. While the research has yet to be peer-reviewed, reception of the research has been met with piqued interest.
For now, the research is certainly something to think over. With larger climate swings predicted over the next century, would the molten core compensate more for the atmospheric change? Thus, are we destined to see more seismic activity as a result of already devastating climate change issues?
Via: Science Alert