This year, millions of people followed stay-at-home recommendations to try to slow the spread of Covid-19. According to scientists, these precautions made our planet noticeably quieter.
Some geologists study the vibrations that travel through Earth when earthquakes and volcanic eruptions shake the ground. To do so, they use instruments called seismographs, which can also detect rumbling from traffic, trains, factories, and other human activities. That prompted Thomas Lecocq, an earthquake scientist at the Royal Observatory of Belgium, to post a graph on Twitter. It revealed that anthropogenic, or human-made, noise decreased by a third when people in Belgium started staying home.
Scientists around the world responded with similar observations, even stating that the quiet allowed them to detect small earthquakes that normally go unnoticed. “It shows we are all fighting the pandemic together,” says Lecocq, “and our efforts are visible in the seismic data.”