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Development and Demonstration of a Freezing Drizzle Algorithm for Roadway Environmental Sensing Systems

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Development and Demonstration of a Freezing Drizzle Algorithm for Roadway Environmental Sensing Systems Development and Demonstration of a Freezing Drizzle Algorithm for Roadway Environmental Sensing Systems http://aurora-program.org Aurora Project 2007-04 Final Report October 2012 About Aurora Aurora is an international program of collaborative research, development and deployment in the field of road and weather information systems (RWIS), serving the interests and needs of public agencies. The Aurora vision is to deploy RWIS to integrate state-of-the-art road and weather forecasting technologies with coordinated, multi-agency weather monitoring infrastructures. It is hoped this will facilitate advanced road condition and weather monitoring and forecasting capabilities for efficient highway maintenance, and the provision of real-time information to travelers. Disclaimer Notice The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the information presented herein. The opinions, findings and conclusions expressed in this publication are those of the authors and not necessarily those of the sponsors. The sponsors assume no liability for the contents or use of the information contained in this document. This report does not constitute a standard, specification, or regulation. The sponsors do not endorse products or manufacturers. Trademarks or manufacturers’ names appear in this report only because they are considered essential to the objective of the document. Non-Discrimination Statement Iowa State University does not discriminate on the basis of race, color, age, religion, national origin, sexual orientation, gender identity, genetic information, sex, marital status, disability, or status as a U.S. veteran. Inquiries can be directed to the Director of Equal Opportunity and Compliance, 3280 Beardshear Hall, (515) 294-7612. Iowa Department of Transportation Statements Federal and state laws prohibit employment and/or public accommodation discrimination on the basis of age, color, creed, disability, gender identity, national origin, pregnancy, race, religion, sex, sexual orientation or veteran’s status. If you believe you have been discriminated against, please contact the Iowa Civil Rights Commission at 800-457-4416 or the Iowa Department of Transportation affirmative action officer. If you need accommodations because of a disability to access the Iowa Department of Transportation’s services, contact the agency’s affirmative action officer at 800-262-0003. The preparation of this report was financed in part through funds provided by the Iowa Department of Transportation through its “Second Revised Agreement for the Management of Research Conducted by Iowa State University for the Iowa Department of Transportation” and its amendments. The opinions, findings, and conclusions expressed in this publication are those of the authors and not necessarily those of the Iowa Department of Transportation or the U.S. Department of Transportation Federal Highway Administration. Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient’s Catalog No. Aurora Project 2007-04 4. Title and Subtitle 5. Report Date Development and Demonstration of a Freezing Drizzle Algorithm for Roadway October 2012 Environmental Sensing Systems 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Leon Osborne Aurora Project 2007-04 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Surface Transportation Weather Research Center University of North Dakota 11. Contract or Grant No. Grand Forks, North Dakota 12. Sponsoring Organization Name and Address 13. Type of Report and Period Covered Aurora Program Federal Highway Administration Final Report Iowa Department of Transportation U.S. Department of Transportation 14. Sponsoring Agency Code 800 Lincoln Way 1200 New Jersey Avenue SE Pooled Fund SPR 72-00-0003-042 Ames, Iowa 50010 Washington, DC 20590 15. Supplementary Notes Visit www.aurora-program.org for color PDFs of this and other research reports. 16. Abstract The primary goal of this project is to demonstrate the accuracy and utility of a freezing drizzle algorithm that can be implemented on roadway environmental sensing systems (ESSs). The types of problems related to the occurrence of freezing precipitation range from simple traffic delays to major accidents that involve fatalities. Freezing drizzle can also lead to economic impacts in communities with lost work hours, vehicular damage, and downed power lines. There are means for transportation agencies to perform preventive and reactive treatments to roadways, but freezing drizzle can be difficult to forecast accurately or even detect as weather radar and surface observation networks poorly observe these conditions. The detection of freezing precipitation is problematic and requires special instrumentation and analysis. The Federal Aviation Administration (FAA) development of aircraft anti-icing and deicing technologies has led to the development of a freezing drizzle algorithm that utilizes air temperature data and a specialized sensor capable of detecting ice accretion. However, at present, roadway ESSs are not capable of reporting freezing drizzle. This study investigates the use of the methods developed for the FAA and the National Weather Service (NWS) within a roadway environment to detect the occurrence of freezing drizzle using a combination of icing detection equipment and available ESS sensors. The work performed in this study incorporated the algorithm developed initially and further modified for work with the FAA for aircraft icing. The freezing drizzle algorithm developed for the FAA was applied using data from standard roadway ESSs. The work performed in this study lays the foundation for addressing the central question of interest to winter maintenance professionals as to whether it is possible to use roadside freezing precipitation detection (e.g., icing detection) sensors to determine the occurrence of pavement icing during freezing precipitation events and the rates at which this occurs. 17. Key Words 18. Distribution Statement ESS—freezing drizzle algorithm—freezing rain—pavement conditions— No restrictions. precipitation—Rosemount 872C2 sensor—RWFRF 19. Security Classification (of this 20. Security Classification (of this 21. No. of Pages 22. Price report) page) Unclassified. Unclassified. 21 NA Form DOT F 1700.7 (8-72) Reproduction of completed page authorized DEVELOPMENT AND DEMONSTRATION OF A FREEZING DRIZZLE ALGORITHM FOR ROADWAY ENVIRONMENTAL SENSING SYSTEMS Final Report October 2012 Author Leon Osborne Surface Transportation Weather Research Center University of North Dakota Grand Forks, North Dakota Sponsored by the Aurora Program, the Iowa Department of Transportation, and the Federal Highway Administration (FHWA) FHWA Pooled Fund Study SPR-3(042): AK, IA, IL, IN, KS, MI, MN, ND, NV, NY, OH, Ontario MOT, PA, Quebec MOT, SD, Sweden NRA, TN, UT, VA, WI Preparation of this report was financed in part through funds provided by the Iowa Department of Transportation through its Research Management Agreement with the Institute for Transportation (Aurora Project 2007-04) A report from Aurora Program Institute for Transportation Iowa State University 2711 South Loop Drive, Suite 4700 Ames, IA 50010-8664 Phone: 515-294-8103 Fax: 515-294-0467 www.intrans.iastate.edu TABLE OF CONTENTS ACKNOWLEDGMENTS ............................................................................................................ vii INTRODUCTION ...........................................................................................................................1 BACKGROUND .............................................................................................................................1 Detection ..............................................................................................................................2 METHODOLOGY ..........................................................................................................................3 Rosemount Freezing Rain Sensor ........................................................................................3 Data Collection ....................................................................................................................4 Data Collection and Analysis...............................................................................................6 RESULTS ........................................................................................................................................9 CONCLUSIONS............................................................................................................................10 RECOMMENDATIONS ...............................................................................................................11 REFERENCES ..............................................................................................................................12 APPENDIX A. ROSEMOUNT SENSOR SPECIFICATIONS ....................................................13 Description .........................................................................................................................13 Specifications .....................................................................................................................13 v LIST OF FIGURES Figure 1. Rosemount 872C2 icing detector .....................................................................................4 Figure 2. The Rosemount Aerospace Corporation Model 872C2 icing detector
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