The files below show the ratio of and difference between time-dependent and time-independent versions of the UCERF3 model. UCERF2 comparisons are provided for reference. For each UCERF3 map, time-dependent and time-independent hazard curves were computed using the five NGAW2 ground motion models that are being used in the 2014 national seismic hazard map; the three NGAW1 models that were used in the 2008 NSHMP were used to compute UCERF2 curves. The maps are the ratio, or difference, of the peak horizontal ground acceleration (PGA) and 5-Hz and 1-Hz spectral accelerations with a 2% probability of being exceeded in 50 years.
UC2 and UC3 in filenames are shorthand for UCERF2 and UCERF3, respectively.