Dr. Wald is a Seismologist with the USGS in Golden. He is involved in research, development & operations of several real-time earthquake information systems at the USGS National Earthquake Information Center. He developed and manages “ShakeMap”, “Did You Feel it?”, & is responsible for developing other systems for post-earthquake response & pre-earthquake mitigation, including ShakeCas
Wald's scientific interests include the characterization of rupture processes from complex recent and historic earthquakes using combined geodetic, teleseismic, and strong motion data; waveform modelling and inversion; analysis of ground motion hazards and site effects; earthquake source physics; and modelling earthquake-induced landslides, liquefaction, and losses, macroseismic intensity, building damage, financial and human impact, rapid damage and impact assessment, earthquake scenario development and mitigation planning and drills, and communication with the media, public, and emergency managers.
Previously at Caltech, and now at the Colorado School of Mines, Wald has advised dozens of post-doctoral, graduate, and undergraduate student research projects. Wald directly supervises 10 PhD level scientists and 5 five BS and MS level support staff, and supervises several students. Wald serves on several PhD committees at this time. This research has resulted in more than 450 professional publications that David has authored or co-authored, including journal papers, USGS publication series, conference papers, and published abstracts.
Education:
Post-doctoral Fellow, Geophysics, National Research Council, USGS, Pasadena, 1995
Ph.D., Geophysics, California Institute of Technology, Pasadena, CA, 1993
M.S., Geophysics, University of Arizona, Tucson, AZ, 1986
B.S., Geology & Physics, St. Lawrence University, Canton, NY, 1984
Science and Products
Developing and Implementing an International Macroseismic Scale (IMS) for Earthquake Engineering, Earthquake Science, and Rapid Damage Assessment
The Blind Zone of Earthquake Early Warning
Future Opportunities in Regional and Global Seismic Network Monitoring and Science
Operational Earthquake Forecasting – Implementing a Real-Time System for California
A Global Hybrid Vs30 Map with a Topographic-Slope-Based Default and Regional Map Insets
An Open Repository of Earthquake-Triggered Ground-Failure Inventories
Shakemap earthquake scenario: Building Seismic Safety Council 2014 Event Set (BSSC2014)
Seismic multi-hazard and impact estimation via causal inference from satellite imagery
Comment on “Which earthquake accounts matter” by Susan E. Hough and Stacey S. Martin
Evaluation of intensity prediction equations (IPEs) for small-magnitude earthquakes
An efficient Bayesian framework for updating PAGER loss estimates
The US Geological Survey ground failure product: Near-real-time estimates of earthquake-triggered landslides and liquefaction
ShakeMap operations, policies, and procedures
Amateur radio operators help fill earthquake donut holes
Quantifying nuisance ground motion thresholds for induced earthquakes
Assessing the long-term earthquake risk for the US National Bridge Inventory (NBI)
Financial risk innovation: Development of earthquake parametric triggers for contingent credit instruments
Human behavioral response in the Ridgecrest earthquakes: Assessing immediate actions based on data from “Did You Feel It?”
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
ShakeCast
An application for automating ShakeMap delivery to critical users and for facilitating notification of shaking levels at user-selected facilities.
Science and Products
- Science
Developing and Implementing an International Macroseismic Scale (IMS) for Earthquake Engineering, Earthquake Science, and Rapid Damage Assessment
The USGS “Did You Feel It” (DYFI) is an extremely popular way for members of the public to contribute to earthquake science and earthquake response. DYFI has been in operation for nearly two decades (1999-2019) in the U.S., and for nearly 15 years globally. During that period the amount of data collected is astounding: Over 5 million individual DYFI intensity reports—spanning all magnitude and dis...The Blind Zone of Earthquake Early Warning
Release Date: MAY 29, 2020 Residents in California, Oregon, and Washington have been told that earthquake early warning (EEW) is at their doorstep and will alert them to the shaking from an earthquake before it arrives. Some media reports have said there will be “up to a minute of warning”. The problem is, for onshore earthquakes these claims are exaggerated, and under some conditions a warning is...Future Opportunities in Regional and Global Seismic Network Monitoring and Science
The past decade has seen improvements in computational efficiency, seismic data coverage, and communication technology - driven by societal expectation for timely, accurate information. While aspects of earthquake research have taken advantage of this evolution, the adoption of improvements in earthquake monitoring has not been fully leveraged. In real-time monitoring, earthquakes are characterizeOperational Earthquake Forecasting – Implementing a Real-Time System for California
It is well know that every earthquake can spawn others (e.g., as aftershocks), and that such triggered events can be large and damaging, as recently demonstrated by L’Aquila, Italy and Christchurch, New Zealand earthquakes. In spite of being an explicit USGS strategic-action priority (http://pubs.usgs.gov/of/2012/1088; page 32), the USGS currently lacks an automated system with which to forecast s... - Data
A Global Hybrid Vs30 Map with a Topographic-Slope-Based Default and Regional Map Insets
Time-averaged shear wave velocity over the upper 30 meters of the earth's surface (Vs30) is a key parameter for estimating ground motion amplification as both a predictive and diagnostic tool for earthquake hazards. A first-order approximation of Vs30 is commonly obtained via a topographic slope-based or terrain proxy due to the widely available nature of digital elevation models. However, better-An Open Repository of Earthquake-Triggered Ground-Failure Inventories
Earthquake-triggered ground-failure, such as landsliding and liquefaction, can contribute significantly to losses, but our current ability to accurately include them in earthquake hazard analyses is limited. The development of robust and transportable models requires access to numerous inventories of ground failure triggered by earthquakes that span a broad range of terrains, shaking characteristiShakemap earthquake scenario: Building Seismic Safety Council 2014 Event Set (BSSC2014)
This is a catalog of earthquake scenarios, represented as ShakeMaps. A ShakeMap is a USGS product that facilitates communication of earthquake effects by portraying a map of the severity of shaking. Maps of shaking severity are provided in terms of macroseismic intensity, peak ground acceleration, peak ground velocity, and spectral accelerations (at 0.3, 1.0 and 3 sec oscillator periods). - Multimedia
- Publications
Filter Total Items: 142
Seismic multi-hazard and impact estimation via causal inference from satellite imagery
Rapid post-earthquake reconnaissance is important for emergency responses and rehabilitation by providing accurate and timely information about secondary hazards and impacts, including landslide, liquefaction, and building damage. Despite the extensive collection of geospatial data and satellite images, existing physics-based and data-driven methods suffer from low estimation performance due to thComment on “Which earthquake accounts matter” by Susan E. Hough and Stacey S. Martin
In their analysis of the U.S. Geological Survey’s (USGS) “Did You Feel It?” (DYFI) data Hough and Martin (2021) claim, among other assertions, that the following:Socioeconomic and geopolitical factors can introduce biases in the USGS’ characterization of earthquakes and their effects, especially if online data collection systems are not designed to be broadly accessible;These biases can, in turn,Evaluation of intensity prediction equations (IPEs) for small-magnitude earthquakes
This study assesses existing intensity prediction equations (IPEs) for small unspecified magnitude (M ≤3.5) earthquakes at short hypocentral distances (Dh) and explores such earthquakes’ contribution to the felt shaking hazard. In particular, we consider IPEs by Atkinson and Wald (2007) and Atkinson et al. (2014), and evaluate their performance based on “Did You Feel It” (DYFI) reports and recorAn efficient Bayesian framework for updating PAGER loss estimates
We introduce a Bayesian framework for incorporating time-varying noisy reported data on damage and loss information to update near real-time loss estimates/alerts for the U.S. Geological Survey’s Prompt Assessment of Global Earthquakes for Response (PAGER) system. Initial loss estimation by PAGER immediately following an earthquake includes several uncertainties. Historically, the PAGER’s alertingThe US Geological Survey ground failure product: Near-real-time estimates of earthquake-triggered landslides and liquefaction
Since late 2018, the US Geological Survey (USGS) ground failure (GF) earthquake product has provided publicly available spatial estimates of earthquake-triggered landslide and liquefaction hazards, along with the qualitative hazard and population exposure-based alerts for M > 6 earthquakes worldwide and in near real time (within ∼30 min). Earthquake losses are oftentimes greatly aggravated by theShakeMap operations, policies, and procedures
The US Geological Survey’s ShakeMap is used domestically and globally for post-earthquake emergency management and response, engineering analyses, financial instruments, and other decision-making activities. Recent developments in the insurance, reinsurance, and catastrophe bond sectors link payouts of potentially hundreds of millions of dollars to ShakeMap products. Similarly, building codes, posAmateur radio operators help fill earthquake donut holes
If you’ve ever seen tall antennas rising from everyday residences in your community and wondered what they are for, it could be that those homes belong to ham radio enthusiasts who enjoy communicating with each other over the airwaves. In addition to having fun with their radios and finding camaraderie, many ham radio operators are also prepared to help neighbors and authorities communicate duringQuantifying nuisance ground motion thresholds for induced earthquakes
Hazards from induced earthquakes are a growing concern with a need for effective management. One aspect of that concern is the “nuisance” from unexpected ground motions, which have the potential to cause public alarm and discontent. In this article, we borrow earthquake engineering concepts to quantify the chance of building damage states and adapt them to quantify felt thresholds for induced eartAssessing the long-term earthquake risk for the US National Bridge Inventory (NBI)
We estimate annualized earthquake loss associated with over 600,000 bridges located throughout the contiguous United States. Each year, the Federal Highway Administration, in partnership with State Departments of Transportation, undertake a massive exercise to update the National Bridge Inventory (NBI) by combining data from states, federal agencies, local jurisdictions, and tribal governments. ThFinancial risk innovation: Development of earthquake parametric triggers for contingent credit instruments
The Inter-American Development Bank (IDB) has developed financial risk management strategies for natural disasters focusing primarily on the emergency phase of the catastrophes where financial support is more cost-efficient and certainly most needed. The main IDB financial instrument to provide liquidity in the aftermath of catastrophic events is the Contingent Credit Facility (CCF). The CCF is aHuman behavioral response in the Ridgecrest earthquakes: Assessing immediate actions based on data from “Did You Feel It?”
Human behavioral response to earthquake ground motion has long been a subject of multidisciplinary interest and research. In most versions of seismic intensity scales, human perceptions and behavior are one component of the assignment of intensity. Public health research has shown that actions taken during earthquakes have a significant impact on the incidence of injury or the maintenance of safetNon-USGS Publications**
References in Google Scholar**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
- Software
ShakeCast
An application for automating ShakeMap delivery to critical users and for facilitating notification of shaking levels at user-selected facilities.
- News