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What to expect when you are expecting earthquake early warning

We present a strategy for earthquake early warning (EEW) alerting that focuses on providing users with a target level of performance for their shaking level of interest (for example, ensuring that users receive warnings for at least 95 per cent of the occurrences of that shaking level). We explore the factors that can affect the accuracy of EEW shaking forecasts including site conditions (which ca
Sarah E. Minson, Elizabeth S. Cochran, Jessie Kate Saunders, Sara McBride, Stephen Wu, Annemarie S. Baltay, Kevin R. Milner

Seismic sources in the aleutian cradle of tsunamis

No abstract available.
Robert C. Witter, Richard W. Briggs, Tina Dura, Simon E. Engelhart, Alan Nelson

A study on the effect of site response on California seismic hazard map assessment

Prior studies have repeatedly shown that probabilistic seismic hazard maps from several different countries predict higher shaking than that observed. Previous map assessments have not, however, considered the influence of site response on hazard. Seismologists have long acknowledged the influence of near-surface geology, in particular low-impedance sediment layers, on earthquake ground-motion at
Molly M. Gallahue, Leah Marschall Salditch, Madeleine C. Lucas, James S. Neely, Seth Stein, Norman A. Abrahamson, Tessa Williams, Susan E. Hough

Testing the ShakeAlert earthquake early warning system using synthesized earthquake sequences

We test the behavior of the United States (US) West Coast ShakeAlert earthquake early warning (EEW) system during temporally close earthquake pairs to understand current performance and limitations. We consider performance metrics based on source parameter and ground‐motion forecast accuracy, as well as on alerting timeliness. We generate ground‐motion times series for synthesized earthquake seque
Maren Böse, Jennifer Andrews, Colin T O'Rourke, Deborah L. Kilb, Angela Lux, Julian Bunn, Jeffrey McGuire

Spatially continuous models of aleatory variability in seismic site response for southern California

We develop an empirical, spatially continuous model for the single-station within-event (ϕSS) component of earthquake ground motion variability in the Los Angeles area. ϕSS represents event-to-event variability in site response or remaining variability due to path effects not captured by ground motion models. Site-specific values of ϕSS at permanent seismic network stations were estimated during o
Grace Alexandra Parker, Annemarie S. Baltay, Eric M. Thompson

Performance of NGA-East GMMs and site amplification models relative to CENA ground motions

We investigate bias in ground motions predicted for Central and Eastern North America (CENA) using ground motion models (GMMs) combined with site amplification models developed in the NGA-East project. Bias is anticipated because of de-coupled procedures used in the development of the GMMs and site amplification models. The NGA-East GMMs were mainly calibrated by adjusting CENA data to a reference
Maria E. Ramos-Sepulveda, Grace Alexandra Parker, Meibai Li, Okan Ilhan, Youssef M. A. Hashash, Ellen M. Rathje, Jonathan P. Stewart

Earthquake early warning: Toward modeling optimal protective actions

Over the past few years early earthquake warning systems have been incorporated into earthquake preparation efforts in many locations around the globe. These systems provide an excellent opportunity for advanced warning of ground shaking and other hazards associated with earthquakes. This study aims to optimize this advanced warning for individuals inside a building when the alert is received. A c
M. Wood, X. Zhang, X. Zhao, Sara McBride, Nicolas Luco, D. Baldwin, T. Covas

2018 M7.1 Anchorage and 2021 M7.2 Nippes, Haiti earthquake case studies for Virtual Earthquake Reconnaissance Team (VERT) activation protocols, policies, and procedures to gather earthquake response footage

The collection of online videos and imagery to use in disaster reconnaissance is increasing in frequency, due to accessibility of platforms and the ubiquitous nature of smartphones and recording devices. In this short article, we explore the processes, goals, and utility of Virtual Emergency Reconnaissance Teams (VERTs) to collect footage and imagery of geohazards (earthquakes, volcanoes, tsunamis
Sara McBride, J. Bellizzi, S. Gin, G. Henry, D. F. Sumy, D. Baldwin, E. Fischer

Update on the Center for Engineering Strong-Motion Data (CESMD)

he Center for Engineering Strong-Motion Data (CESMD), an internationally utilized joint center of the U.S. Geological Survey (USGS) and the California Geological Survey (CGS), provides a unified access point for earthquake strong-motion records and station metadata from the CGS California Strong-Motion Instrumentation Program (CSMIP), the USGS National Strong-Motion Project (NSMP), the USGS Advanc
L. Hagos, H. Haddadi, Lisa Sue Schleicher, Jamison Haase Steidl, Lind Gee, M. Dhar

Western U.S. deformation models for the 2023 update to the U.S. National Seismic Hazard Model

This report describes geodetic and geologic information used to constrain deformation models of the 2023 update to the National Seismic Hazard Model (NSHM), a set of deformation models to interpret these data, and their implications for earthquake rates in the western United States. Recent updates provide a much larger data set of Global Positioning System crustal velocities than used in the 2014
Fred Pollitz, Eileen L. Evans, Edward H. Field, Alexandra Elise Hatem, Elizabeth H. Hearn, Kaj M Johnson, Jessica R. Murray, Peter M. Powers, Zheng-Kang Shen, Crystal Wespestad, Yuehua Zeng

GPS velocity field of the Western United States for the 2023 National Seismic Hazard Model update

Global Positioning System (GPS) velocity solutions of the western United States (WUS) are compiled from several sources of field networks and data processing centers for the 2023 U.S. Geological Survey National Seismic Hazard Model (NSHM). These solutions include both survey and continuous‐mode GPS velocity measurements. I follow the data processing procedure of Parsons et al. (2013) for the Unifo
Yuehua Zeng

Viscoelastic fault-based model of crustal deformation for the 2023 update to the U.S. National Seismic Hazard Model

The 2023 update to the National Seismic Hazard (NSHM) model is informed by several deformation models that furnish geodetically estimated fault slip rates. Here I describe a fault‐based model that permits estimation of long‐term slip rates on discrete faults and the distribution of off‐fault moment release. It is based on quantification of the earthquake cycle on a viscoelastic model of the seismo
Fred Pollitz