David J. Wald

Last updated
David J. "Dave" Wald
DavidBirdwatching.jpg
Born
David Jay Wald

May 6, 1962
Greenwich, Connecticut
Known for
Board member of
SpouseLisa Wald
Academic background
Education
Website usgs.gov/staff-profiles/david-j-wald

David Jay Wald (born May 6, 1962 Greenwich, Connecticut) [1] is a seismologist with the U.S. Geological Survey (USGS) at the National Earthquake Information Center (NEIC) in Golden, Colorado. [2] He is an affiliated faculty member at the Colorado School of Mines, [3] and served as the editor-in-chief of the Earthquake Engineering Research Institute's (EERI) journal, Earthquake Spectra , from 2018–2022. [4] [5] He also served on the Southern California Earthquake Center Science Planning Committee, 2014–2020. [6]

Contents

Wald is involved in the research, development, and operations of real-time information systems at the USGS National Earthquake Information Center. [7] He has developed and manages products such as ShakeMap and the community-science system Did You Feel It?. He is also responsible for developing other systems for post-earthquake response and pre-earthquake mitigation, such as ShakeCast and PAGER. [8] He has also contributed to the USGS Ground Failure product. [9] [10] As well as management of these systems, Wald's research also focuses on characterization of rupture processes from complex earthquakes, analysis of ground motions and site effects, and modeling earthquake-induced events. [11]

On top of his publications, Wald is also known for hosting events and giving lectures about geophysics topics, including a "Provost’s Lecture" at Stony Brook University [12] and an EERI Younger Members Committee webinar. [13]

Education

Wald received his B.S. in Geology and Physics from St. Lawrence University in 1984. He then completed his M.S. in Geophysics from the University of Arizona in 1986. [8] He worked in Pasadena, California for Woodward-Clyde Consultants from 1986–1988 on seismic hazard assessments for the Diablo Canyon Power Plant. [14] David went on to the California Institute of Technology (Caltech) in Pasadena and was awarded his Ph.D. in Geophysics in 1993. [14]

Wald then began working at the USGS in Pasadena in 1993 as a National Research Council Post-Doctoral Fellow and stayed on there as a researcher. He and his wife, Lisa Wald, [15] who also works for the USGS, [16] later transferred to the Golden, Colorado USGS office to work at the NEIC. [14]

Products

Wald was a developer of PAGER, a post-earthquake analytic system. He is also the primary developer and distributor of ShakeMap. [17] Other products of note developed or managed by Wald include:

Did You Feel It?

Did You Feel It? civilian responses to the 2023 Turkey earthquake. Did You Feel It%3F.jpg
Did You Feel It? civilian responses to the 2023 Turkey earthquake.

For Did You Feel It? (DYFI), [18] Wald leveraged the work of Lori Dengler and Jim Dewey following the Northridge earthquake. Their large volume of macroseismic phone surveys motivated them to create a "community decimal intensity" by assigning numerical values to individual questionnaire responses that they could calibrate against the Modified Mercalli Intensity scale, the macroseismic intensity scale in use in the U.S. The numerical assignment of intensities from questionnaires lent itself naturally to automating the entire process of data collection, intensity assignment, and publishing via the internet, which today creates community-sourced maps of perceived intensity after an earthquake. [19]

DYFI has been operating for over two decades (1999–present) [20] in the U.S. and over 18 years globally. The survey has collected over 6 million individual DYFI intensity reports during that period. DYFI allows for high rates and quantities of macroseismic data collection. High-quality MMI maps can be made almost immediately with complete coverage at a higher resolution than in the past. [21]

ShakeCast

In and around 2000, via contacts with the Caltech ERA, Wald began interacting with many utility and lifeline operators. A common query was, "Given a ShakeMap, how can I tell what the level of shaking was at each of my facilities?” Working initially with Phil Naecker, an IT and infrastructure consultant, and with support from Loren Turner of the California Department of Transportation (Caltrans), David's team prototyped ShakeCast—short for ShakeMap Broadcast. ShakeCast was developed as a post-earthquake situational awareness application that automatically retrieves earthquake shaking data from ShakeMap to compare ground shaking intensity measures against a user’s facilities. [22]

ShakeCast is now a fully automated software system for delivering specific ShakeMap products to critical users and triggering established post-earthquake response protocols. ShakeCast generates potential damage assessments and inspection priority notifications, maps, and web-based products for critical users, emergency managers, and anyone specified on a need-to-know basis. [23] [24]

Honors

Research output

As per Scopus, Wald has over 11 thousand citations and an h-index of 50, [33] whereas according to Google Scholar, he boasts over 21 thousand citations and a 67 h-index. [34] Semantic Scholar lists him between the two, with over 15 thousand citations and a 57 h. [35]

Selected publications since 2020:

Related Research Articles

The Modified Mercalli intensity scale measures the effects of an earthquake at a given location. This is in contrast with the seismic magnitude usually reported for an earthquake.

Peak ground acceleration (PGA) is equal to the maximum ground acceleration that occurred during earthquake shaking at a location. PGA is equal to the amplitude of the largest absolute acceleration recorded on an accelerogram at a site during a particular earthquake. Earthquake shaking generally occurs in all three directions. Therefore, PGA is often split into the horizontal and vertical components. Horizontal PGAs are generally larger than those in the vertical direction but this is not always true, especially close to large earthquakes. PGA is an important parameter for earthquake engineering, The design basis earthquake ground motion (DBEGM) is often defined in terms of PGA.

<span class="mw-page-title-main">Strong ground motion</span> Type of earthquake

In seismology, strong ground motion is the strong earthquake shaking that occurs close to a causative fault. The strength of the shaking involved in strong ground motion usually overwhelms a seismometer, forcing the use of accelerographs for recording. The science of strong ground motion also deals with the variations of fault rupture, both in total displacement, energy released, and rupture velocity.

Seismic magnitude scales are used to describe the overall strength or "size" of an earthquake. These are distinguished from seismic intensity scales that categorize the intensity or severity of ground shaking (quaking) caused by an earthquake at a given location. Magnitudes are usually determined from measurements of an earthquake's seismic waves as recorded on a seismogram. Magnitude scales vary on what aspect of the seismic waves are measured and how they are measured. Different magnitude scales are necessary because of differences in earthquakes, the information available, and the purposes for which the magnitudes are used.

The 1986 San Salvador earthquake occurred at 11:49:26 local time on 10 October 1986 with a moment magnitude of 5.7 and a maximum Mercalli intensity of IX (Violent). The shock caused considerable damage to El Salvador's capital city of San Salvador and surrounding areas, including neighboring Honduras and Guatemala.

The 1998 Adana–Ceyhan earthquake occurred at 16:55 local time on 27 June with a moment magnitude of 6.3 and a maximum intensity of IX (Destructive) on the European macroseismic scale. The total economic loss was estimated at about US$1 billion.

The 2007 Alum Rock earthquake occurred on October 30 at 8:04 p.m. Pacific Daylight Time in Alum Rock Park in San Jose, in the U.S. state of California. It measured 5.6 on the moment magnitude scale and had a maximum Mercalli intensity of VI (Strong). The event was then the largest in the San Francisco Bay Area since the 1989 Loma Prieta earthquake, which measured 6.9 on the moment magnitude scale, but was later surpassed by the 2014 South Napa earthquake. Ground shaking from the Alum Rock quake reached San Francisco and Oakland and other points further north. Sixty thousand felt reports existed far beyond Santa Rosa, as far north as Eugene, Oregon.

The 1991 Uttarkashi earthquake occurred at 02:53:16 Indian Standard Time (UTC+05:30) on 20 October with a moment magnitude of 6.8 and a maximum Mercalli intensity of IX (Violent). This thrust event was instrumentally recorded and occurred along the Main Central Thrust in the Uttarkashi and Gharwal regions of the Indian state of Uttarakhand. High intensity shaking resulted in the deaths of at least 768 people and the destruction of thousands of homes.

<span class="mw-page-title-main">Isoseismal map</span> Type of map used in seismology

In seismology, an isoseismal map is used to show lines of equally felt seismic intensity, generally measured on the Modified Mercalli scale. Such maps help to identify earthquake epicenters, particularly where no instrumental records exist, such as for historical earthquakes. They also contain important information on ground conditions at particular locations, the underlying geology, radiation pattern of the seismic waves, and the response of different types of buildings. They form an important part of the macroseismic approach, i.e. that part of seismology dealing with noninstrumental data. The shape and size of the isoseismal regions can be used to help determine the magnitude, focal depth, and focal mechanism of an earthquake.

The 1995 Colima–Jalisco earthquake occurred on October 9 at 15:35 UTC with a moment magnitude of 8.0 and a maximum Mercalli intensity of VIII (Severe). The shock occurred off the coast of Jalisco, Mexico, where a tsunami was triggered that affected a 200 km (120 mi) stretch of the coast. The earthquake could be felt in Mexico City and in high-rise buildings in Dallas and Houston. In Mexico, the Cihuatlan-Manzanillo was the most severely affected area. At least 49 people died and 100 were injured.

<span class="mw-page-title-main">PAGER</span> U.S. Geological Survey-operated monitoring system for earthquakes

Prompt Assessment of Global Earthquakes for Response (PAGER) is a monitoring system for earthquakes. The service is operated by the U.S. Geological Survey, from its office in Golden, Colorado.

Seismic intensity scales categorize the intensity or severity of ground shaking (quaking) at a given location, such as resulting from an earthquake. They are distinguished from seismic magnitude scales, which measure the magnitude or overall strength of an earthquake, which may, or perhaps may not, cause perceptible shaking.

The Advanced National Seismic System (ANSS) is a collaboration of the U.S. Geological Survey (USGS) and regional, state, and academic partners that collects and analyzes data on significant earthquakes to provide near real-time information to emergency responders and officials, the news media, and the public. Such information is used to anticipate the likely severity and extent of damage, and to guide decisions on the responses needed.

The 1934 Hansel Valley earthquake occurred on March 12 at approximately 8:05 a.m. MST with a moment magnitude of 6.6 and a maximum Mercalli intensity of VIII (Severe). The shock originated in the Hansel Valley at the north end of the Great Salt Lake in Utah in the United States. Damage was mostly confined to vulnerable buildings, and two people died. The dip-slip (normal) fault that generated the shock ruptured the surface of the ground and other geologic features were documented. A large aftershock occurred three hours after the initial event and may have caused additional damage.

The 1981 Westmorland earthquake occurred at 05:09 Pacific Daylight Time on April 26. The moderate strike-slip shock took place in the Imperial Valley of Southern California, just north of the Mexico–United States border. No injuries or deaths occurred, but damage was estimated at $1–3 million. With a Mercalli intensity of VII, this was one of fifteen intensity VII or greater shocks in the Imperial Valley that were observed in the 20th century up until April 1981. The region experiences large stand-alone events and earthquake swarms due to its position in an area of complex conditions where faulting transitions from strike-slip movement to the north and divergence to the south.

An earthquake occurred at 2:13 p.m. on Friday, July 19, 2019, and affected millions of many in the middle of the day. Several seismological institutes determined a magnitude of about 5.3 and the epicentral region appeared to be south of Mt Parnitha, ~20 km NW of the Athens metropolitan area. Nearly 20 years before, on the 7th September 1999, Athens was struck by a 6.0 magnitude earthquake.

<span class="mw-page-title-main">2015 Lefkada earthquake</span> Earthquake in Greece

The 2015 Lefkada earthquake occurred on November 17, 2015, 10:40:07 (EEST) with a moment magnitude of 6.5 located 19 km Southwest of the Greek island of Lefkada along with a depth of 11 km and intensities reaching as high as VIII (Severe) on the Modified Mercalli Scale. Two people lost their lives in the event and 4–8 others were hospitalized with injuries.

<span class="mw-page-title-main">ShakeMap</span> U.S. Geological Survey earthquake mapping and tracking system

ShakeMap is a product of the U.S. Geological Survey (USGS) to map the shaking of earthquakes. According to the USGS, "ShakeMaps provide near-real-time maps of ground motion and shaking intensity following significant earthquakes. These maps are used by federal, state, and local organizations, both public and private, for post-earthquake response and recovery, public and scientific information, as well as for preparedness exercises and disaster planning." The system's development was led largely by USGS seismologist David J. Wald with others.

References

  1. ↑ "David Wald". ORCID . Retrieved 2023-06-03.
  2. ↑ "David J. Wald, Ph.D." ICONHIC2016. Retrieved 2023-06-03.
  3. ↑ "Faculty and Staff". Department of Geophysics. Colorado School of Mines . Retrieved 2023-06-01.
  4. ↑ Ortiz, Rita. "New Earthquake Spectra Editor David Wald". Earthquake Engineering Research Institute . Retrieved 2023-06-01.
  5. ↑ Elizabeth (2022-12-01). "Welcoming Jack Baker as Editor-in-Chief and Helen Crowley as Editor of Earthquake Spectra". Earthquake Engineering Research Institute . Retrieved 2023-06-01.
  6. ↑ "wald: David J. Wald". Southern California Earthquake Center . Retrieved 2023-06-03.
  7. ↑ "David J. Wald". UCLA Samueli School Of Engineering. Retrieved 2023-06-01.
  8. 1 2 "David J Wald". U.S. Geological Survey . Retrieved 2023-02-22.
  9. ↑ "Geophysics Seminar - David Wald "Citizen Science and Macroseismic Intensity in Earthquake Research, Engineering, & Risk Assessment," USGS". Stanford Doerr School of Sustainability . 26 January 2023. Retrieved 2023-06-03.
  10. ↑ Allstadt, Kate E; Thompson, Eric M; Jibson, Randall W; Wald, David J; Hearne, Michael; Hunter, Edward J; Fee, Jeremy; Schovanec, Heather; Slosky, Daniel; Haynie, Kirstie L (2022). "The US Geological Survey ground failure product: Near-real-time estimates of earthquake-triggered landslides and liquefaction". Earthquake Spectra. 38 (1): 5–36. Bibcode:2022EarSp..38....5A. doi: 10.1177/87552930211032685 . ISSN   8755-2930.
  11. ↑ "David Wald". Natural Hazards Center || Workshop 2018 || Bio Page. Retrieved 2023-06-03.
  12. ↑ "May 4 Provost's Lecture: Challenges in Real-time Earthquake Shaking and Impact Estimation". SBU News. Stony Brook University. 2022-04-28. Retrieved 2023-06-03.
  13. ↑ "EERI Webinar: Case Studies of Financial Decision-Making using Near Real time Post Earthquake Information, by Dr. David J. Wald". Geoengineer.org. Retrieved 2023-06-03.
  14. 1 2 3 "David Wald (PhD '93), Research Geophysicist, USGS". Heritage Project. Caltech. 2022-08-05. Retrieved 2023-06-01.
  15. ↑ "Lisa Wald, Vice-President – Evergreen Audubon". Evergreen Nature Center. Retrieved 2023-06-03.
  16. ↑ "Lisa A Wald". U.S. Geological Survey . Retrieved 2023-02-23.
  17. ↑ U.S. Geological Survey (2017). "ShakeMap – Earthquake Ground Motion and Shaking Intensity Maps". U.S. Geological Survey. doi:10.5066/F7W957B2.
  18. ↑ "Did You Feel It?". U.S. Geological Survey . Retrieved 2023-06-03.
  19. ↑ Dengler, L. A.; Dewey, J. W. (1998-04-01). "An intensity survey of households affected by the Northridge, California, earthquake of 17 January 1994". Bulletin of the Seismological Society of America. 88 (2): 441–462. Bibcode:1998BuSSA..88..441D. doi:10.1785/BSSA0880020441. ISSN   1943-3573. S2CID   130602800.
  20. ↑ "Did You Feel It?". U.S. Geological Survey . Retrieved 2023-06-03.
  21. ↑ Atkinson, G. M.; Wald, D. J. (2007-05-01). ""Did You Feel It?" Intensity Data: A Surprisingly Good Measure of Earthquake Ground Motion". Seismological Research Letters. 78 (3): 362–368. Bibcode:2007SeiRL..78..362A. doi:10.1785/gssrl.78.3.362. ISSN   0895-0695.
  22. ↑ "USGS Open-File Report 2008-1158: ShakeCast Manual". pubs.usgs.gov. Retrieved 2023-03-01.
  23. ↑ Lin, Kuo-Wan; Wald, David J. (2008). "ShakeCast Manual". U.S. Geological Survey Open-File Report 2008-1158. Open-File Report. doi: 10.3133/ofr20081158 .
  24. ↑ Wald, D. J.; Jaiswal, K. S.; Marano, K.; Hearne, M.G.; Lin, K.; Slosky, D.; Allstadt, K. E.; Thompson, E. M.; Worden, C. B.; Hayes, G. P.; Quitoriano, V. (2020). "AN UPDATE ON USGS NEAR-REAL-TIME EARTHQUAKE SHAKING AND IMPACT PRODUCTS" (PDF). Proceedings of the 17th World Conference on Earthquake Engineering.
  25. ↑ "IRIS/SSA Distinguished Lecture Series". IRIS . Retrieved 2023-03-01.
  26. ↑ Elizabeth (2021-11-12). "David J. Wald Receives 2022 William B. Joyner Lecture Award". Earthquake Engineering Research Institute . Retrieved 2023-06-03.
  27. ↑ "Abstracts – 2018". Colorado Scientific Society. Retrieved 2023-06-03.
  28. ↑ mortimer (4 March 2014). "David Wald to Deliver 2014 EERI Distinguished Lecture". Earthquake Engineering Research Institute . Retrieved 2023-03-01.
  29. 1 2 "Dave Wald wins The Eugene M. Shoemaker Award for Lifetime Achievement in Communications". Earthquake Engineering Research Institute . Retrieved 2023-02-22.
  30. ↑ "David Wald". AGU . Retrieved 2023-03-01.
  31. ↑ "David J. Wald Selected as 2022 Joyner Lecturer". Seismological Society of America . Retrieved 2023-06-03– via LinkedIn.
  32. ↑ "David J. Wald". Seismological Society of America . Retrieved 2023-06-01.
  33. ↑ "Wald, David Jay". Scopus (Author details). Retrieved 2023-06-01.
  34. ↑ "David J Wald". Google Scholar . Retrieved 2023-06-01.
  35. ↑ "D. Wald". Semantic Scholar . Retrieved 2023-06-01.
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