Norman A. Abrahamson Sean Kamran Ahdi Timothy D. Ancheta Linda Al Atik Ralph J. Archuleta Gail M. Atkinson David M Boore Kenneth W. Campbell Brian S-J Chiou Victor Contreras Robert B. Darragh Sahar Derakhshan Jennifer L Donahue Nick Gregor Zeynep Gulerce Izzat M Idriss Chengxin Jiang Tadahiro Kishida Albert R. Kottke Nicolas Kuehn Dongyoup Kwak Annie O-L Kwok Person Lin Jorge Macedo Silvia Mazzoni Saburoh Midorikawa Sifat Muin Grace Alexandra Parker Sanaz Rezaeian Hongjun Si Walter J Silva Jonathan P. Stewart Melanie Walling Katie Wooddell Robert R Youngs Yousef Bozorgnia 2021 <div class="hlFld-Abstract"><div class="abstractSection abstractInFull"><p>This article summarizes the Next Generation Attenuation (NGA) Subduction (NGA-Sub) project, a major research program to develop a database and ground motion models (GMMs) for subduction regions. A comprehensive database of subduction earthquakes recorded worldwide was developed. The database includes a total of 214,020 individual records from 1,880 subduction events, which is by far the largest database of all the NGA programs. As part of the NGA-Sub program, four GMMs were developed. Three of them are global subduction GMMs with adjustment factors for up to seven worldwide regions: Alaska, Cascadia, Central America and Mexico, Japan, New Zealand, South America, and Taiwan. The fourth GMM is a new Japan-specific model. The GMMs provide median predictions, and the associated aleatory variability, of RotD50 horizontal components of peak ground acceleration, peak ground velocity, and 5%-damped pseudo-spectral acceleration (PSA) at oscillator periods ranging from 0.01 to 10 s. Three GMMs also quantified “within-model” epistemic uncertainty of the median prediction, which is important in regions with sparse ground motion data, such as Cascadia. In addition, a damping scaling model was developed to scale the predicted 5%-damped PSA of horizontal components to other damping ratios ranging from 0.5% to 30%. The NGA-Sub flatfile, which was used for the development of the NGA-Sub GMMs, and the NGA-Sub GMMs coded on various software platforms, have been posted for public use.</p></div></div> application/pdf 10.1177/87552930211056081 en Sage Publications NGA-Subduction research program article