Forecasting ocean wave-induced seismic noise

Ocean waves induce the power peak in the seismic ground motion seen everywhere in the world between 0.03 and ~ 1 Hz, defining the seismic noise baseline. The precise generation mechanisms are well understood, and the dependence of seismic noise on sea weather has been precisely quantified using long-term time series. However, this knowledge has never been exploited to forecast the seismic noise background. Here we report the prediction of the seismic noise spectrum around 1 Hz at the Low-Noise Underground Laboratory (LSBB) in Rustrel, for up to 16 days in advance, limited by the time span of sea weather forecasts. We first characterize the dependence of the seismic noise at the LSBB on the Mediterranean Sea and Atlantic Ocean weather, using buoy data for 2020-2021. We exploit significant correlation in the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>0.15</mml:mn> <mml:mspace></mml:mspace> <mml:mtext>Hz</mml:mtext> <mml:mo><</mml:mo> <mml:mi>f</mml:mi> <mml:mo><</mml:mo> <mml:mn>2.5</mml:mn> <mml:mspace></mml:mspace> <mml:mtext>Hz</mml:mtext></mml:mrow> </mml:math> frequency band to make predictions, converting sea weather forecasts into seismic noise forecasts. The expected seismic background noise can be used to optimize the performance and running costs of scientific and industrial activities, by scheduling them during quiet intervals or adopting adaptive data analysis techniques to identify target signals in the predicted noise.