The health, economic and social crisis caused by the COVID-19 pandemic is having consequences worldwide. Not all are necessarily negative, but some are quite curious, and are the logical result of the decline in human activity on planet Earth . One of the most talked about has been the decrease in CO2 at the planetary level; China was one of the countries to notice this drop, which achieved reductions of 25%.
Now, the journal Nature has published the conclusions of a team of seismologists from the Royal Observatory center, in Brussels, Belgium, who have observed a remarkable decrease in the Earth’s seismic movements of approximately one third compared to the level of ‘seismic noise’ that it usually occurs around these dates. Seismic noise is defined as the vibrations of the planet’s crust.
Natural events, such as the internal activity of the planet, cause the earth’s crust to move, causing this series of “hums”, which can be captured by seismologists. But also human activity, such as moving vehicles or industrial machinery, causes seismic noise. Scientists believe that this decrease in the seismic activity of the planet is a consequence of the decrease in human activity as part of the measures to contain the spread of COVID-19.
According to Thomas Lecocq, a seismologist at the Royal Observatory in Belgium, a decrease of this magnitude is only observed, momentarily, for a short period around Christmas.
As can be seen in the graph above, with data from the measurement instrument, the fall in seismic noise in Belgium coincides with the beginning of the application of containment measures , such as the closure of schools, restaurants and other public places as of 14 of March; and a ban on all non-essential travel as of March 18.
Ears are sharpened to listen to the Earth
The current drop in seismic noise, which, as we say, is a logical consequence of the phenomenon of the coronavirus crisis, has in turn increased the sensitivity of the observatory equipment, improving its ability to detect waves in the same high-frequency range. than noise.
The Belgian facility’s surface seismometer is now almost as sensitive to small earthquakes and quarry explosions as a homologous detector buried in a shaft 100 meters deep; a remarkably curious event.
Although this assessment has taken place in the Belgian observatory, it is foreseeable that this event is occurring in all those parts of the world that have adopted similar measures. Celeste Labedz, a geophysics graduate student at the California Institute of Technology in Pasadena, tweeted that a station in Los Angeles had detected a similar drop in noise: “The drop is really wild.”
