Seismic noises were found to drop significantly in many stations around the globe during the early stage of the COVID-19 lockdown. The UC Riverside Seismology Journal Club discussed this topic at that time and decided to have a look at the noise level of our nearby stations in southern California. 

To our surprise, many stations did not record a drop during the early stage of the COVID-19 pandemic. Of the 19 stations of the Southern California Seismic Network surveyed, we found that only five show a similar extent of drop in anthropogenic seismic noise comparable to the Christmas holiday break in 2019. This suggests that the human activity that caused seismic noise did not significantly reduce during the COVID-19 pandemic near most surveyed stations in southern California. 

We go on to explore why this is the case. A further analysis implies that the primary seismic noise source in southern California might be traffic, and the continuation of industrial traffic, such as cargo transportation, during the COVID-19 pandemic may be the reason why many stations did not record a noise drop.

Learn more in our publication Wu et al., 2021, and my Jan-2021 presentation sides @UCR. 

Last updated Aug-28-2023