Real-time Tornado Touchdown Monitoring from the Kentucky Seismic and Strong Motion Network

Real-time Tornado Touchdown Monitoring from the Kentucky Seismic and Strong Motion Network Abstract Kentucky has experienced several devastating storm systems in the past decade. Most recently, the December 10-11, 2021, system produced multiple tornadoes, the worst of which was an EF4, with a track longer than 165 miles, which injured more than 1,000 people, caused more than 50 deaths, and destroyed more than 2,000 structures. Although the National Weather Service issues tornado warnings, obtaining ground-truth verification of tornado touchdowns, which present the greatest wind hazard, requires chance eyewitness accounts or post-event verification. Likely tornado touchdowns are identified more routinely by modern radar instruments and data processing techniques, however manual verification is still needed, which is more challenging nighttime hours and in remote parts of the Commonwealth. Thus, new techniques and data are needed to improve the remote identification of tornados that have touched down. The Kentucky Geological Survey (KGS) operates a network of 23 seismic stations in 17 counties across the Commonwealth and two additional stations in northwestern Tennessee. Eighteen of these stations are connected to the internet and produce data acquired at KGS in near-real-time. The KGS also acquires data from all states that border Kentucky through near-real-time data sharing. Thus, the KGS handles large datasets capable of monitoring seismic events as well other sources of seismic waves. During the energetic December 2021 storms, changes in ground vibrations in Tennessee and Kentucky were detected by seismic stations in and near to verified storm tracks. Of particular importance, seismologists at the KGS retroactively identified anomalous signals at a station less than five miles from a verified touched-down tornado. This observation indicates that seismic data has the potential to provide a powerful, continuous, on-the-ground tool available to corroborate tornado touchdowns ostensibly identified using radar data. This proposed project will assemble seismic datasets in Kentucky and elsewhere that correlate with verified tornadoes and identify systematic signals that assist with tornadic activity vulnerability analyses based on concurrent correlations between seismic vibrations and meteorological data. In addition, the pathway to serve future touchdown warnings in near-real-time to assist emergency managers and local officials will be established. This project will install several new stations to increase KGS’s seismic and tornadic monitoring capabilities including broadband seismometers and infrasound sensors. Finally, this project will also collect new earthquake data at the seismic stations in and around Kentucky to assist with earthquake mitigation planning: a list of earthquakes including date, time, location, and magnitude will be produced and served on KGS servers.