Data Release for the 2018 Update of the U.S. National Seismic Hazard Model: Where, Why, and How Much Probabilistic Ground Motion Maps Changed

This dataset presents where, why, and how much probabilistic ground motions have changed with the 2018 update of the National Seismic Hazard Model (NSHM) for the conterminous U.S. (CONUS) vs. the 2014 NSHM. In the central and eastern U.S., hazard changes are the result of updated ground motion models (further broken down by median and epistemic uncertainty, aleatory variability, and site effects models) and gridded seismicity models. In the western U.S., hazard changes are the result of updated ground motion models in four urban areas with deep sedimentary basins and gridded seismicity models. Probabilistic ground motion changes (2% in 50 years probability of exceedance for a firm rock site, VS30 = 760 m/s, NEHRP site class boundary B/C) are presented for 153,255 sites across the CONUS for 0.2s and 1s spectral acceleration. A MATLABTM script is provided so that the dataset can be searched by site location. A statistical analysis of the dataset was also performed and is provided in a table (Table 1). This dataset is discussed in the journal article titled: "The 2018 Update of the U.S. National Seismic Hazard Model: Where, Why, and How Much Probabilistic Ground Motion Maps Changed" by Petersen et al. (2021) located at http://doi.org/10.1177/8755293020988016.