Coronavirus lockdowns hushed seismic noise around the world

Driving, drilling, walking, flying and other human activities vibrate the Earth's surface, creating seismic noise.

What they found: Using data from 268 seismic stations in 117 countries, researchers measured the effects of lockdowns on high-Frequency (4–14 Hz) Seismic Ambient Noise (hiFSAN), which corresponds to vibrations typically generated by human activities.

• They observed the effects of lockdowns at 185 stations and found a "near-global reduction in noise, commencing in China in late Jan 2020, then followed by Europe and the rest of the world" from March to April 2020.
• The noise level reduction lasted longer and was at times quieter than the Christmas to New Years period, Thomas Lecocq, a seismologist at the Royal Observatory of Belgium, and his colleagues from around the world report Thursday in the journal Science.

• The drops were more pronounced in more-populated areas (New York and Sri Lanka), but were observed in less-populated regions (for example, Germany's Black Forest) as well.

The big picture: "This is the first time to our knowledge that this kind of effect is visible on such a widespread area — the whole globe — and for such a long time period," says Lecocq.