Importance of OEF to the USGS Earthquake Hazards Program Michael L. Blanpied USGS Earthquake Hazards Program For Powell Center March 16, 2015

Is USGS already doing OEF? Reports of the Working Group on California Earthquake Probabilities: 1988, 1990, 1999, 2003, 2008 (UCERF2), 2013 (UCERF3). CA Integrated Seismic Network (CISN, includes USGS) publishes foreshock & aftershock forecasts after M≥5 earthquakes in California. STEP 24-hour Probabilistic Seismic Hazard map of California, was published on a USGS website as a real-time operational forecast. CalOES receives forecast advisories from the California Earthquake Prediction Evaluation Council (CEPEC, with USGS members. USGS issues ad hoc formal and informal aftershock probabilities, when requested after major earthquakes, domestic and abroad. –Some based on clustering statistics, when available. –Some based on time-dependent renewal models. –Some based on Coulomb stress calculations.

Rationale for increased effort in OEF USGS bears a responsibility to enhance public safety through effective forecasts, and is often asked for those forecasts. OEF role is obvious. Vetted, approved methods exist for mainshock-aftershock sequences in California, where clustering statistics are known. But we lack vetted methods for calculating dynamic forecasts: (1) outside of CA and outside of the USA, (2) during seismic swarms, (3) in areas subject to induced seismicity, (4) by other methods. Methods in use have not been rigorously tested. Current information products are not visible, effective, nimble, tested, responsive to user needs, or integrated with the existing suite of USGS post-earthquake products. Additional impetus in light of post-L’Aquila events. Utility of OEF has been demonstrated in Italy & New Zealand.

Aftershock forecast for Haiti Developed and released on request from USAID, UN and others. Provides probabilities for earthquakes above M5, M6, M7 over 30 days. Also provides background information and guidance for preparedness. Released in English, French, Spanish and Creole. Developed by USGS group, released three weeks after earthquake.

Goals of OEF Strategic Plan Provide a vision for OEF and the dissemination of related warning messages and products, as an activity of the Earthquake Hazards Program and the Advanced National Seismic System. Develop an integrated program that includes R&D and testing of forecast models, design and testing of forecast products, and integration of methods into network operations. Define the roles of NEPEC, CEPEC, SAFRR, and CSEP. Define user needs and uses for dynamic hazard and risk forecasts. Improve estimates of changes in earthquake probability, hazard, and risk over relevant time periods. Extend capability broadly across the nation. Explore additional methods (e.g., geodesy, Coulomb stress). Define requirements for a structured ~5-year effort.

Structure of OEF at the USGS Research – Perform research earthquake processes; develop forecast algorithms. Model Development – Make the algorithms testable and usable, possibly including real-time data (an entry point for new methods). Model Testing – Test forecast algorithms. Message Design – Determine what products best convey useful information to meet user needs; develop explanatory material. Production – Integrate model and products into seismic networks. Product assessment – Determine if products work as desired.

Status of OEF at USGS Advisory committees have endorsed increased effort in OEF. Several staff attended 2014 international workshop on OEF. Science Appl’s for Risk Reduction (SAFRR) project investigating user needs and best practices in communicating forecasts. Planning underway for an aftershock forecast as a nationwide, operational product of the Advanced National Seismic System. Clustering statistics being developed outside of California. USGS National Earthquake Information Center (NEIC) is considering recommendations on network and catalog needs. USGS hosted a workshop on seismic hazard and forecasting in areas of induced seismicity. One-year model being built. UCERF3 dynamic forecast model for CA is under development. Powell Center is underway.