[ghsc-seminars] GHSC Seminar *TOMORROW* *HYBRID* - Leah Salditch, USGS, March 28, 2023

[Llenos, Andrea L]

Assessing the performance of PSHA using seismic intensity products

Speaker: Leah Salditch
                Geologic Hazards Science Center
                USGS
Location: HYBRID (online and in-person at 1711 Illinois St, Golden, CO, Rm 204)
                 *Non-USGS visitors welcome! Please bring a photo ID and arrive early to allow time to go through security*
Date/Time: Tuesday, March 28, 2023 10-11AM MDT

Abstract: How well does the USGS National Seismic Hazard Model (NSHM) forecast ground shaking? Using past observations in a hindcast approach, I evaluate hazard models via performance metrics. Probabilistic seismic hazard assessments (PSHA) based on current practice consistently overpredict historical observations of seismic intensity. Independently prepared PSHA for the U.S., Japan, Italy, Nepal, and France all display this trend. Numerical studies indicate that in an ideal case the observed shaking is equally likely to be above or below predictions, and that observations should be closer to the prediction as observation time increases. Yet, I will show that hazard maps primarily overpredict historical observations of shaking and no consistent improvement appears with longer observation times. However, when comparing PSHA with modern intensity products like Did You Feel It? and ShakeMap, I find substantial improvement in performance metrics, despite their relatively short observation periods. This talk will explore some possible reasons for these observed differences, which may have important implications for hazard assessment, and highlight future directions indicated by these results.

Bio: Leah Salditch is a Mendenhall Post-Doctoral Fellow at the USGS Geological Hazards Science Center in Golden, CO. Her research at GHSC focuses on assessing the performance of the National Seismic Hazard Model by leveraging flagship products like DYFI? and ShakeMap. To improve the performance of the NSHM, she is studying non-ergodic ground motion models and improvements to ground-motion-intensity-conversion-equations. She received a Ph.D. in Earth and Planetary Sciences and an M.S. in Statistics from Northwestern University in 2021 where she studied earthquake hazards and recurrence models. She was the recipient of the 2021 AGU Natural Hazards Section Graduate Research Award, and currently serves on several committees for the Seismological Society of America.

For questions, comments, or speaker suggestions, please contact the GHSC Seminar Committee: Andrea Llenos <allenos at usgs.gov>, Benjamin Murphy <bmurphy at usgs.gov>, Lauren Schaefer <lschaefer at usgs.gov>


________________________________________________________________________________
Microsoft Teams meeting
Join on your computer or mobile app
Click here to join the meeting<https://gcc02.safelinks.protection.outlook.com/ap/t-59584e83/?url=https%3A%2F%2Fteams.microsoft.com%2Fl%2Fmeetup-join%2F19%253ameeting_ZWI3OWFlOTQtZTVkZS00OGIzLTg3MzUtMThkMTgwMDI0Zjc5%2540thread.v2%2F0%3Fcontext%3D%257b%2522Tid%2522%253a%25220693b5ba-4b18-4d7b-9341-f32f400a5494%2522%252c%2522Oid%2522%253a%252250f012ff-efbf-4efc-b34b-d5361c4364e5%2522%257d&data=05%7C01%7Cghsc-seminars%40geohazards.usgs.gov%7C45ff8a1b707b4aae063308db2edc48c1%7C0693b5ba4b184d7b9341f32f400a5494%7C0%7C0%7C638155295862123881%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=DhjliYqIcq1Gl%2BFN5E9kBphU7cVhmBSfD2Kp2z1c6gA%3D&reserved=0>
Meeting ID: 276 852 793 971
Passcode: F6GHjw
Download Teams<https://gcc02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.microsoft.com%2Fen-us%2Fmicrosoft-teams%2Fdownload-app&data=05%7C01%7Cghsc-seminars%40geohazards.usgs.gov%7C45ff8a1b707b4aae063308db2edc48c1%7C0693b5ba4b184d7b9341f32f400a5494%7C0%7C0%7C638155295862123881%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=rBIm3hxZwXWFEmsyjiR4n0ZIr0SBCVw7I%2FyRr%2BlVG0w%3D&reserved=0> | Join on the web<https://gcc02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.microsoft.com%2Fmicrosoft-teams%2Fjoin-a-meeting&data=05%7C01%7Cghsc-seminars%40geohazards.usgs.gov%7C45ff8a1b707b4aae063308db2edc48c1%7C0693b5ba4b184d7b9341f32f400a5494%7C0%7C0%7C638155295862123881%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=DjjLt0Z5%2FKWxbjdZ%2FQot5gGr5wce59Fkvnm64AIhwik%3D&reserved=0>
Learn More<https://gcc02.safelinks.protection.outlook.com/?url=https%3A%2F%2Faka.ms%2FJoinTeamsMeeting&data=05%7C01%7Cghsc-seminars%40geohazards.usgs.gov%7C45ff8a1b707b4aae063308db2edc48c1%7C0693b5ba4b184d7b9341f32f400a5494%7C0%7C0%7C638155295862123881%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=APzoDwS%2BWYJ26n58wo9kFpdZmJpp%2B2J0d2ig70kVObQ%3D&reserved=0> | Meeting options<https://gcc02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fteams.microsoft.com%2FmeetingOptions%2F%3ForganizerId%3D50f012ff-efbf-4efc-b34b-d5361c4364e5%26tenantId%3D0693b5ba-4b18-4d7b-9341-f32f400a5494%26threadId%3D19_meeting_ZWI3OWFlOTQtZTVkZS00OGIzLTg3MzUtMThkMTgwMDI0Zjc5%40thread.v2%26messageId%3D0%26language%3Den-US&data=05%7C01%7Cghsc-seminars%40geohazards.usgs.gov%7C45ff8a1b707b4aae063308db2edc48c1%7C0693b5ba4b184d7b9341f32f400a5494%7C0%7C0%7C638155295862123881%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=uy3tTbiVhJ8rw7PQCXB1JVjL6Bc7tdOhgb4EXsF2zfA%3D&reserved=0>
________________________________________________________________________________
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://geohazards.usgs.gov/pipermail/ghsc-seminars/attachments/20230327/b311784d/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: text/calendar
Size: 8944 bytes
Desc: not available
URL: <http://geohazards.usgs.gov/pipermail/ghsc-seminars/attachments/20230327/b311784d/attachment-0001.ics>