The shock waves of civilization travel through rocky ground and, at times, ricochet around the globe, as geologists know from decades of listening for earthquakes with sensitive seismometers. The human pulses come from heavy traffic, football games, rock concerts, fireworks, subways, mine explosions, rock drilling, factories, jackhammers, industrial blasts and other activities. In 2001, vibrations from the collapse of the World Trade Center registered in five states. “The length and quiescence of this period represents the longest and most coherent global seismic noise reduction in recorded history,” the scientists reported on Thursday in the journal Science. The quieting, they added, resulted from social distancing, industrial shutdowns and drops in travel and tourism.

Source: International New York Times July 23, 2020 18:00 UTC