The Earth vibrated for 9 days last year, and scientists finally know why
Last year, the Earth vibrated for nine consecutive days, puzzling scientists worldwide. Now, they finally know why the strange phenomenon happened.
The vibration set alarms among seismologists. Seismic instruments picked up a signal, but it did not look like an earthquake but a constant hum. CNN said none of them had seen that before.
According to the broadcaster, dozens of scientists captured the vibration and were curious about its origin. They had picked up similar signals, but none had lasted that long.
The researchers traced the signal back to a location. They found the culprit behind the strange vibration: a 650-foot-high megatsunami caused by a landslide in Greenland.
The discovery triggered an international investigation by scientists to understand how the megatsunami caused the entire planet to vibrate for nine days.
According to CNN, 68 scientists from 15 countries conducted a year-long investigation. They examined seismic data and simulated tsunami waves.
Dr. Kristian Svennevig from the National Geological Surveys for Denmark and Greenland (GEUS) told CNN that the vibration resulted from a cascading hazard.
It all started when a gigantic glacier in a remote part of a Greenland region called Dickson Fjord began to melt due to the rising Arctic temperatures.
The glacier was holding up the base of a massive mountain. As the glacier melted, the hill became increasingly unstable, CNN explains. It finally collapsed into a landslide, causing the megatsunami.
Enough dirt and rocks to fill 10,000 Olympic-size pools fell into the water, lifting one of the highest tsunamis recorded. The wave got trapped inside the fjord, slapping back and forth between the rock walls.
That phenomenon, named a seiche, is not new. But this trapped wave swung every 90 seconds for an unprecedented amount of time: over a week. Scientists had never detected a seiche that long.
“Had I suggested a year ago that a seiche could persist for nine days, people would shake their heads and say that’s impossible,” Mr. Svennevig told CNN while comparing the discovery to watching a new color in a rainbow.
The discovery of the mechanism that triggered a 9-day Earth vibration also opened a new door for science. It shows the potential seismic consequences of Climate Change.