The Societal Value of the HYSPLIT Air Dispersion Model Final Report to the NOAA Air Resources Laboratory Seth Villaneuva, Kathryne Cleary, and Alan Krupnick Report 21-04 February 2021 The Social Value of the HYSPLIT Model A About the Authors Seth Villanueva is a research analyst at Resources for the Future. He graduated from UC Santa Barbara in 2019 with a BA in economics and a minor in mathematics. At UCSB, Villanueva was an undergraduate Gretler Fellow research assistant studying the economic effects of scaled wind power generation. Villanueva’s work at RFF includes clean energy policy analysis, value of information research as part of the VALUABLES Consortium, and energy policy analysis for RFF’s annual Global Energy Outlook report. Kathryne Cleary is a senior research associate at Resources for the Future. Her work at RFF focuses primarily on electricity policy with the Future of Power Initiative and includes work on carbon pricing, electricity market design, and electrification. Outside of her work on electricity, Cleary has worked on economic studies on the value of information. Cleary holds an MEM with a focus on energy policy from the Yale School of the Environment and a BA in economics and environmental policy from Boston University. Alan Krupnick is a senior fellow at Resources for the Future. Krupnick’s research focuses on analyzing environmental and energy issues, in particular, the benefits, costs and design of pollution and energy policies, both in the United States and abroad. He leads RFF’s research on the risks, regulation and economics associated with shale gas development and has developed a portfolio of research on issues surrounding this newly plentiful fuel. Acknowledgements We thank Mark Cohen, Lead Scientist, Atmospheric Transport and Dispersion, Air Resources Laboratory (ARL), NOAA, for his invaluable help, including running HYSPLIT for the Husky event, and Joseph J. Moore, Warning Coordination Meteorologist, NOAA/National Weather Service Duluth, for discussions about the Husky event and HYSPLIT’s use and for pointing us to important documents. We thank Air Licensing Unit Manager Jane Gilbert and Director Jeff Crawford of Maine’s Bureau of Air Quality for meticulous support that was essential to parsing Maine air licensing regulation. We also want to thank Sonny Zinn and Barbara Stunder of ARL, NOAA for information on their event database of HYSPLIT uses, Alice Crawford and Tianfeng Chai and others on the ARL staff for their comments on the draft report and helping to define this project, and our project manager and deputy director of ARL, Ariel Stein, for his encouragement and comments throughout this project and his support of the value of information ideas. Finally, a thank you to our RFF colleagues Matthew Ashenfarb and Alexandra Thompson for their excellent spatial data work. Resources for the Future i About RFF Resources for the Future (RFF) is an independent, nonprofit research institution in Washington, DC. Its mission is to improve environmental, energy, and natural resource decisions through impartial economic research and policy engagement. RFF is committed to being the most widely trusted source of research insights and policy solutions leading to a healthy environment and a thriving economy. The views expressed here are those of the individual authors and may differ from those of other RFF experts, its officers, or its directors. Sharing Our Work Our work is available for sharing and adaptation under an Attribution- NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) license. You can copy and redistribute our material in any medium or format; you must give appropriate credit, provide a link to the license, and indicate if changes were made, and you may not apply additional restrictions. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use. You may not use the material for commercial purposes. If you remix, transform, or build upon the material, you may not distribute the modified material. For more information, visit https://creativecommons.org/licenses/by-nc-nd/4.0/. The Social Value of the HYSPLIT Model ii Abstract The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model, which was developed by NOAA’s Air Resources Lab (ARL), is used in a wide variety of applications to estimate the forward and back trajectories of pollutants. Because HYSPLIT is available for free, its societal value is not easily measured. This study describes its many types of applications and provides a literature review that highlights how the benefits of these uses could theoretically be quantified. However, the heart of the report is quantifying in monetary terms the social value of information that the HYSPLIT model provides to its users and society at large. Both case studies highlight instances in which consulting HYSPLIT led to better information and more informed decisionmaking, with measurable benefits to society. The first case explores the state of Maine’s citing HYSPLIT to prove to the Environmental Protection Agency (EPA) that certain counties were not contributing to ozone exceedances in the state and to petition for those areas to be removed from the ozone transport region, a designation that imposes stricter environmental regulations on polluters. The second case explores the benefits of using HYSPLIT to better inform the evacuation zone following a fire at the Husky Refinery in Duluth, MN. The combined case study values more than exceed the annual cost of maintaining the HYSPLIT model. Resources for the Future iii Contents 1. The VOI 2 1.1. How to Assess the VOI 3 2. Categorization of HYSPLIT Uses 6 2.1. Summary of Recent HYSPLIT Uses 12 2.2. References 13 3. Case Studies 14 3.1. Maine Attainment Designation Case Study 15 3.1.1. Background and Use of HYSPLIT 15 3.1.2. Counterfactual Scenario 17 3.1.3. The Change Scenario 20 3.1.4. Attribution 20 3.1.5. The Benefits of Reclassification 21 3.1.6. Results and Conclusion 24 3.2. Husky Refinery Case Study 25 3.2.1. Background and Use of HYSPLIT 25 3.2.2. The Counterfactuals 29 3.2.3. The Benefits of HYSPLIT 30 3.2.4. Methods and Components of Estimating Health Benefits 32 3.2.5. Health Benefits 40 3.2.6. Evacuation Costs 45 3.2.7. Net Benefits 47 3.2.8. Revealed Preference Estimates 48 The Social Value of the HYSPLIT Model iv 3.2.9. Exceedances 49 3.2.10. Final Results and Case Study Conclusions 51 3.3. Case Study Extrapolation 52 3.4. References 52 4. Literature Review Applicable to HYSPLIT Benefits 54 4.1. Attainment Classification: Documenting Exceptional Events 54 4.1.1. References 55 4.2. Tracking Anthropogenic Sources 56 4.2.1. Heavy Metals 56 4.2.2. Radionuclides 56 4.2.3. References 57 4.3. Tracking Natural Sources of Pollution 58 4.3.1. Volcanic Ash 58 4.3.2. References 59 4.4. Emergency Planning 60 4.4.1. Fire 60 4.4.2. References 61 4.5. Academic Research 62 4.5.1. Allergens 62 4.5.2. Dust 64 4.5.3. References 64 4.6. Cross-Cutting Impacts 65 4.6.1. Health 65 4.6.2. Environmental Impacts 66 Resources for the Future v 4.6.3. References 66 4.7. Option Value 67 4.7.1. References 67 5. Conclusion 68 The Social Value of the HYSPLIT Model vi Introduction Government-run programs are increasingly under scrutiny to prove their value to justify their funding. Since such programs provide resources and tools that are public goods and are generally available for free, they typically lack traditional methods for assessing product value used by private companies, such as a price on the product. Instead, one way to estimate the value of a government program is to assess the value of information (VOI) it provides. Such an assessment requires knowledge of the uses to which it is put, the benefit of those uses, and the counterfactual: what would happen to the activities if the program in question were no longer available. The National Oceanic and Atmospheric Administration (NOAA) Air Resources Lab (ARL) developed the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model to simulate dispersion and forward and back trajectories of pollutants in the atmosphere. HYSPLIT is widely used for a variety of reasons, such as modeling smoke from wildfires, tracing the source of radionuclides, and informing aircraft rerouting in the event of volcanic eruptions. HYSPLIT is distinguished because it is free, accessible, supported, and frequently updated. Additionally, it can run faster than similar models, and the website provides curated meteorological data to drive the model for use and/or download. HYSPLIT’s uses and corresponding benefits are vast and can be difficult to assess because it is available for free to the public. Without a price tag, the user’s willingness to pay (WTP) for such a product is not directly known. However, it is possible to assign a monetary value to many of HYSPLIT’s benefits through techniques developed in the VOI literature, as discussed in section 4, which will help decisionmakers measure this value against the program’s cost and assess its overall net societal value. This report examines those net benefits to society by making monetary estimates where possible. Section 1 covers the concept of value, which defines what we mean by VOI and how we would begin to quantify it. Section 2 categorizes HYSPLIT by use, source, and the corresponding possible benefits from that use, which includes human health, environmental health, property, and administrative benefits, such as time saved and mitigation costs avoided. Section 3 describes the two case studies performed as part of this project, along with the methods and the results.