Data shows ‘seismic noise’ has dropped dramatically in Ireland

9 Apr 2020

Image: © Brice/Stock.adobe.com

With Ireland’s roads largely empty and many now staying at home during the coronavirus pandemic, the country’s ‘seismic noise’ has dropped dramatically.

Along with a sharp decline in greenhouse gases across Europe as a result of most people staying indoors, Ireland’s ‘seismic noise’ has also dropped dramatically in recent weeks.

Using data from the Irish National Seismic Network (INSN), the Dublin Institute for Advanced Studies (DIAS) and Geological Survey Ireland found that seismic noise levels are up to three times lower now than before containment measures were introduced to limit the spread of the coronavirus.

Commenting on the findings, director of seismic networks at DIAS, Dr Martin Möllhoff, said: “Our day-to-day lives result in small ground movements – for example, by cars, trains, building sites and other industries. These human-induced vibrations, called seismic noise by seismologists, vary with the human activity.

“Worldwide social restrictions due to the coronavirus pandemic affect not only levels of air pollution, but also how much the ground beneath our feet vibrates. With the current Covid-19 restrictions on human movement, INSN seismic noise levels have been markedly reduced.”

Graph showing a dramatic drop in seismic noise in Ireland.

Image: DIAS

Easier to detect earthquakes

Similar findings have been seen by seismologists across the world who have been tracking how Covid-19 restrictions have impacted seismic noise levels. The reduced seismic white noise generated by people also brings great benefits to scientific research, according to Prof Chris Bean, head of the geophysics section and director of the School of Cosmic Physics at DIAS.

“Such lowered seismic noise levels can enhance the capability of a seismic network to detect small earthquakes and are testament to the high levels of compliance with Covid-19 movement restrictions,” he said.

It follows other research released by the Irish Centre for High-End Computing that showed an overall reduction in nitrogen dioxide levels across the country between February and March this year.

This was achieved using data from ESA’s Sentinel-5P satellite. However, the data also showed a number of spikes that were most likely associated with fires in rural areas.

Colm Gorey was a senior journalist with Silicon Republic

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