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International Standard Book Number-13: 978-0-309-72537-8
International Standard Book Number-10: 0-309-72537-2
Digital Object Identifier: https://doi.org/10.17226/27933

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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2025. Advancing Risk Communication with Decision-Makers for Extreme Tropical Cyclones and Other Atypical Climate Events. Washington, DC: The National Academies Press. https://doi.org/10.17226/27933.

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WORKSHOP PLANNING COMMITTEE

ANN BOSTROM (Chair), Weyerhaeuser endowed Professor in Environmental Policy at the Evans School of Public Policy and Governance, University of Washington

DEREKA CARROLL-SMITH, Postdoctoral Research Associate, National Institute of Standards and Technology Professional Research Experience Program, University of Maryland College Park

BRAD R. COLMAN, President, American Meteorological Society

WILLIAM C. FUGATE, Principal, Craig Fugate Consulting LLC.

MICHAEL K. LINDELL, Emeritus Professor, Texas A&M University; Affiliate Professor, University of Washington Department of Urban Design and Planning; Affiliate Professor, Boise State University Department of Geosciences; and Affiliate Professor, Oregon State University School of Civil and Construction Engineering

ANDREA B. SCHUMACHER, Project Scientist, Weather Risks and Decisions in Society research group, National Center for Atmospheric Research

J. MARSHALL SHEPHERD, Georgia Athletic Association Distinguished Professor of Geography and Atmospheric Sciences and Director of Atmospheric Sciences Program, University of Georgia

JEANNETTE SUTTON, Associate Professor, Department of Emergency Preparedness and Homeland Security and Director of Emergency and Risk Communication Message Testing Lab, University at Albany

National Academies of Sciences, Engineering, and Medicine Staff

JOHN BEN SOILEAU, Program Officer

HUGH WALPOLE, Associate Program Officer (until March 2024)

KATELYN CREWS, Program Assistant (from March 2024)

RITA GASKINS, Administrative Coordinator (until March 2024)

ROB GREENWAY, Program Associate (until March 2024)

MAGGIE WALSER, Acting Co-Director, Board on Atmospheric Sciences and Climate

Reviewers

This Proceedings of a Workshop was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published proceedings as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the charge. The review comments and draft manuscript remain confidential to protect the integrity of the process.

We thank the following individuals for their review of this proceedings:

ANN BOSTROM, University of Washington

DAPHNE LADUE, University of Oklahoma

KELLY MCCUSKER, Rhodium Group

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the content of the proceedings nor did they see the final draft before its release. The review of this proceedings was overseen by Edwin Schmitt, California Public Utilities Commission. He was responsible for making certain that an independent examination of this proceedings was carried out in accordance with standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the rapporteur(s) and the National Academies.

Contents

ACRONYMS AND ABBREVIATIONS

1 INTRODUCTION

Organization of the Workshop Proceedings

2 COMMUNICATING RISKS OF ATYPICAL TROPICAL CYCLONES: LESSONS FROM HENRI AND HILARY

Forecaster Perspectives on Risk Communication

Discussion

Research Perspectives on Risk Communication

3 RISK COMMUNICATION IN MULTI-HAZARD ENVIRONMENTS: CHALLENGES AND LEARNING OPPORTUNITIES FROM COMPOUNDING HAZARDS AND CASCADING IMPACTS

Keynote Speech - Multi-Hazard Extremes: Definitions, Classifications, and Consequences

Risk Communication Around Cascading and Compounding Hazards

High-Level Summary of Sessions One and Two

Summary of Breakout Discussions: Applying Risk Communications Lessons From Other Hazards to the Tropical Cyclone Context

4 RISK COMMUNICATION AND DECISION MAKING IN COMMUNITIES

Risk Communication Across Scales: Risk Communicators In Communities

Roundtable: Community Leaders and Community Action

High-Level Summary of Sessions Three and Four

5 A RECAP OF THE FIRST DAY OF THE WORKSHOP

6 PRACTICAL TRANSLATION OF RISK IN THE PUBLIC ARENA

Risk Communication Innovations and New Frontiers in Tropical Cyclone Communication: Public Sector

Messaging Technology Walkthrough

Risk Communication Innovations and New Frontiers in Tropical Cyclone Communication: Private Sector

7 NEW APPROACHES TO UNMET NEEDS: COMMUNICATION FOR THE WHOLE COMMUNITY

Keynote Speech: Jargon, Technical Language, and Plain Language

Communicating Uncertainty and Probabilistic Information About Tropical Cyclone Tracks, Timing, and Severity

Examples of Access and Functional Needs

High-Level Summary of Sessions Five and Six

8 IMPLICATIONS FOR THE FUTURE

Roundtable Discussion: Workshop Retrospective and Implications for the Future

Workshop Wrap-Up

REFERENCES

APPENDIX A: PUBLIC MEETING AGENDAS

APPENDIX B: COMMITTEE BIOGRAPHIES

Boxes and Figures

BOXES

1-1 Statement of Task

FIGURES

3-1 A visual representation of how the literature has framed different types of extreme weather and climate hazards

3-2 Forecast map of the Houston area during Hurricane Harvey with expected rainfall in inches and flooding indicated by color, alongside public comments about this forecast compiled by Lindner

3-3 Hurricane Dorian (2019) threat graphics (top) that incorporate probabilistic information to provide a reasonable worst-case scenario for each of the four hazards (e.g., wind, storm surge), a situation overview (bottom left), and the four hazard threat levels relative to each other with a forecast confidence rating (bottom right)

3-4 Three rapidly intensifying storms with multiple hazards (e.g., tornados, extreme heat)

4-1 Survey results from EMs ranking what type of information was most important at key points in a severe weather event: 3 days, 1 day to 1 hour, and 15 minutes before the forecasted storm

6-1 A depiction of the Weather Channel’s Surge-FX

7-1 Different visualizations of the cone of uncertainty using the cone-only technique (right) and the ensemble technique (left)

7-2 A research prototype designed by physical scientists depicting the likelihood of various wind thresholds being exceeded over the next 5 days for Hurricane Ian (2022)

7-3 A socio-behavioral model of warning response

Acronyms and Abbreviations