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D Bausch

Publications and source records attributed to D Bausch.

2 recordsLinked to original sources

Development of a domestic earthquake alert protocol combining the USGS pager and FEMA Hazus systems

The U.S. Geological Survey’s PAGER automated alert system provides rapid (10-20 min) loss estimates in terms of ranges of fatalities and economic impact for all significant earthquakes around the globe. In contrast, FEMA’s Hazus software, which is currently operated manually by FEMA personnel internally within several hours of any large domestic earthquake, provides more detailed loss information quantified in terms of physical damage to the building stock, as well as a broad range of social and economic consequences estimated at a much higher spatial resolution (census-tract level). Hazus was originally designed for FEMA’s mitigation planning, but has been used of late for post-earthquake situational awareness. While the quick alerts generated automatically by the PAGER system are a suitable way to initially identify consequences for earthquakes, there remains a need to provide detailed loss information for facilitating a wider array of post-earthquake decisions among emergency managers. As such, we have developed a prototype summary product that takes advantage of the benefits of both these loss models for significant domestic earthquakes. The signature product, a new twoPAGER report, will serve as a supplement to the widely deployed standard onePAGER product for all significant domestic earthquakes. Page one is the standard, automated PAGER alert content, with summary alert levels for overall fatality and economic loss estimates, as well as summary content on recent earthquakes, structure vulnerability, and historical secondary hazards. As soon as the Hazus run using the most up-to-date version of the USGS ShakeMap is completed and reviewed by both agencies, the second alert page will be generated and delivered via the USGS website as an update. This second page will contain a summary of the more comprehensive Hazus model results, including spatially distributed estimates of: affected population, economic impact, non-fatal injuries, displaced households, and damage to structures (including potential building safety evaluation requirements). This enhancement does not affect the timeliness and the importance of the initial (onePAGER) alerting content for significant earthquakes; however, the twoPAGER report will provide more detailed, damage and loss/impact content for the Nation in the critical hours following a damaging earthquake.

Conference Paper

Annualized earthquake loss estimates for California and their sensitivity to site amplification

Input datasets for annualized earthquake loss (AEL) estimation for California were updated recently by the scientific community, and include the National Seismic Hazard Model (NSHM), site‐response model, and estimates of shear‐wave velocity. Additionally, the Federal Emergency Management Agency’s loss estimation tool, Hazus, was updated to include the most recent census and economic exposure data. These enhancements necessitated a revisit to our previous AEL estimates and a study of the sensitivity of AEL estimates subjected to alternate inputs for site amplification. The NSHM ground motions for a uniform site condition are modified to account for the effect of local near‐surface geology. The site conditions are approximated in three ways: (1) by VS30 (time‐averaged shear‐wave velocity in the upper 30 m) value obtained from a geology‐ and topography‐based map consisting of 15 VS30 groups, (2) by site classes categorized according to National Earthquake Hazards Reduction Program (NEHRP) site classification, and (3) by a uniform NEHRP site class D. In case 1, ground motions are amplified using the Seyhan and Stewart (2014) semiempirical nonlinear amplification model. In cases 2 and 3, ground motions are amplified using the 2014 version of the NEHRP site amplification factors, which are also based on the Seyhan and Stewart model but are approximated to facilitate their use for building code applications. Estimated AELs are presented at multiple resolutions, starting with the state level assessment and followed by detailed assessments for counties, metropolitan statistical areas (MSAs), and cities. AEL estimate at the state level is ∼$3.7 billion, 70% of which is contributed from Los Angeles–Long Beach–Santa Ana, San Francisco–Oakland–Fremont, and Riverside–San Bernardino–Ontario MSAs. The statewide AEL estimate is insensitive to alternate assumptions of site amplification. However, we note significant differences in AEL estimates among the three sensitivity cases for smaller geographic units.

California