Why are earthquakes like the one that hit Turkey and Syria so hard to predict?

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The causes of large earthquakes, such as the magnitude 7.8 temblor that struck Turkey and Syria on Monday, are well known. That doesn’t make them any easier to predict.

Despite advances in both science and technology, it remains virtually impossible to know precisely when and where earthquakes will occur.

«Earthquake prediction has always been kind of the holy grail,» said Wendy Bohon, an earthquake geologist who works as a communications strategist at NASA’s Goddard Space Flight Center in Maryland. “If we could tell people exactly when an earthquake will strike, we could take steps to mitigate it. But the Earth is a very complicated system.”

Part of the challenge is that the very nature of earthquakes makes them unpredictable events. When one happens, it happens quickly.

“An earthquake is not like a slow train that eventually picks up speed. It’s a sudden, accelerated event,» said Ben van der Pluijm, a professor of geology at the University of Michigan.

Earthquakes also tend to happen with little or no warning. Although scientists have investigated potential precursor events, from changes in underground sounds to potential increases in a region’s seismic activity to changes in animal behavior, so far they have been unable to identify any consistent signs that tremor is imminent.

The lack of a clear pattern makes it difficult to create reliable forecasts similar to weather reports.

In addition, the processes that underpin earthquakes—the crushing and colliding of tectonic plates and the energy that builds up as a result—tend to unfold over long periods of time. Scientists can, for example, estimate that an earthquake is likely to hit an area sometime in the next 200 years, which can be specific to geologic time scales. On human time scales? Not so much.

“We have an incredibly good idea of ​​where we expect earthquakes, and even the sizes we can expect for large earthquakes in these areas, but that doesn’t help us reduce it down to a human time scale,” van der Pluijm said.

The US Geological Survey is even more direct on the subject. “Neither the USGS nor any other scientist has ever predicted a major earthquake. We don’t know how, and we don’t expect to know how at any time in the foreseeable future.» the agency said on its website.

Still, there are ways to prepare. The USGS has developed an early warning system called ShakeAlert that detects when a significant earthquake has occurred in California, Oregon, and Washington and then broadcasts radio, television, and cell phone alerts that say a strong tremor is imminent. In most cases, alerts offer only a few seconds of warning, but that time can be extremely valuable, van der Pluijm said.

“Twenty seconds sounds like a very short time, but it’s enough time for you to find a place under a desk to protect yourself,” he said. «It’s not a prediction, but ShakeAlert is a big step forward because it can minimize the inevitable impact.»

One of the most important ways to prepare for an earthquake is to be aware of the risks, Bohon said. For policymakers, this means ensuring that critical infrastructure is protected in earthquake-prone areas.

“What we need to do is make sure we understand what can happen and build to resist that,” he said. “We have to make sure that people know what to do. We have to make sure that our cities are able to be resilient in the face of those hazards so that we not only survive the earthquake, we can survive afterward.”

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