Information and transportation applications of weather technologies

Informatics and TransportationApplications of Weather TechnologyMichael A. Rossetti and Thomas A. SeligaJuly 10, 2008

Scope/Definitions> Weather Informatics– Includes the combination of detection, processing, interpretation,formatting, distribution and use of weather information in realtimefor surface transportation operations and management– Utilizes: in-situ sensing (surface stations); remote sensing(satellite, radar, lidar, etc); forecasting and nowcasting products:data networking; and sending, receiving and storing informationvia telecommunication devices (telematics), all combined tocomprise practical elements of an Intelligent TransportationSystem (ITS)….leading to the concept of:> Transportation Weather Informatics (TWI)– Confluence of information derived from the elements of WeatherInformatics to integrate, format and communicate usefulinformation that meets the primary and secondary needs of thesurface transportation community2

Overview/Background> Bridging the gap between weather information providers and surfacetransportation users> Evolving radar capability offers continuous and high-resolutionmonitoring of weather over surface transportation networks> Era of major advances in numerical weather models> Availability of digital forecast databases> Advances in navigation, computer processing and telecommunicationsare enabling technologies> TWI has great potential for the development of indices that canidentify, locate and communicate road weather conditions and hazards> Benefits extend to many users and include improved operationalcapabilities available for real-time decision making and near- and longtermplanning> Two sample case studies: Florida crash in fog/smoke on I-4, Atlantaheavy rain impacts on I-75

Examples of Related US Efforts> Clarus> Maintenance Decision Support System (MDSS)> Vehicle Infrastructure Integration (VII)/Safe Trip21> Meteorological Assimilation and Data InformationSystem (MADIS)> Real-time traffic information (e.g. Smart Traveler)> Wireless mesh networks (developing technology)4

Real Time Traffic Information/Smart TravelerA commercial service in the US that provides trafficinformation to more than 100 million commuters daily throughan affiliate network of more than 2,500 broadcast and digitalmedia customers.- Delivers a simple and intuitive user interface, and ispowered by Maptuit, a leading provider of mapping and navigationsolutions.- Real-time traffic is automatically updated every fewminutes through a local network of traffic reporting centers,providing users with the most current, timely and accurate trafficincident, construction and highway speed information available.- Includes access to RealTraffic, interactive full-color,street-level maps displaying traffic conditions for over 100 majormarkets and door-to-door directions throughout North America.5

Wireless Mesh Networks> Enables computers to communicate to each otherwithout going through central servers or networks.– MIT and other researchers are developing and testingprototype "mesh networks"– Would enable cars to act as roving weather stations,gathering both meteorological and road conditions,and sharing data and related information withneighboring cars through mesh networks. Samplemessages:• Slippery road ahead, slow down NOW!• Dense fog ahead with stopped vehicles in road, use extremecaution!6

Required Resources for a TWI System> Direct access to:– Surface Weather Station Observations– Weather Radar Data– Satellite– Lightning Detection and Reporting System– National and Regional Forecast and NowcastProducts (e.g., Rapid Update Cycle (RUC) II, NAMMM5, UKMET, ECMWF, etc.)– Real-time traffic information– Roadway attributes – physical and environmental– Human factors – localized> Cross-Jurisdictional Cooperation and Participation> Financial Commitment7

Weather Radar Focus: NEXRAD, TDWR andPrivate Sector> More than any other system, weather radar offers unrealized opportunities forapplications to highway traffic management and the associated user community> Resource is both an established technology and continually improving> Opportunities will be further enhanced as deployment of dual polarization capabilitiescome on line; e.g., the US NEXRAD system is expected to have this capability within~5 yrs, and there is potential for similar upgrades on the Terminal Doppler WeatherRadars (TDWR). Commercial systems are also coming on line in major populationcenters. Many other countries have comparable capabilities or can readily acquirethem.> The concept has already been demonstrated; e.g., by using a NEXRAD radar toproduce rainfall-dependent indices that affect driving - a highway wetness index(HWI) and a rainfall visibility impairment index were merged into a combined hazardindex (CHI).> Other indices can also be defined and included in CHI. Examples include effects dueto other traffic and weather attributes such as accidents, traffic volume, windconditions, fog, hail, glare, hazardous and non-hazardous spills, etc.> The products can be mapped directly along routes of interest and tailored for specificusers’ needs. Time domain of the products can typically extend over hours andinclude nowcasting out to around 1-2 hrs with temporal resolutions down to around 1-5 minutes.9

Importance of Wet Roads

Development of Hazard Indices (sample illustrations)> Precipitation– Type– Intensity– Location> Rainfall– Wetness index• Loss of traction• Hydroplaning speed/risk– Visibility impairment– Glare enhancement> Winds– Headwinds– Cross winds– Gusts> Other Physical and Human Factor Attributes11

Early Demonstration of NEXRAD-Derived Rainfall DrivingConditions (Wetness and Visibility Impairment)

Traffic Flow Decelerates and Accelerates in Response toHazard IndexACCELERATINGTRAFFICDECELERATINGTRAFFIC

Atlanta NEXRAD, June 30, 200314

Transformation of Radar Measurements to RainfallRate along Designated Route-6Reflectivity Factor: Z(dBZ) = 10log(Z)60-6Filtered Rainfall Rate: R(dBR) = 10log(R)25-550-52015Time (hrs) RE: Current Time = 0-4-3-2403020Time (hrs) RE: Current Time = 0-4-3-21050-5-110-1-1000 20 40 60 80 100 1200Distance (sm) along I-75 in Georgia from S of Forsyth through Atlanta to N of Calhoun0 -150 20 40 60 80 100 120Distance (sm) along I-75 in Georgia from S of Forsyth through Atlanta to N of Calhoun15

150100050-5-1016Roadway Wetness ParameterG- 36G- 20 US-41 I- 85 I- 85 G-120 G- 20G- 23I-675 I-285 I- 20 I-285 I-575 G-1401-5555-105555010100-1055-550-550-55-5-5-5-55-10-1055-5-5-10-5-5-5-510-5-5-10-10-100100-10-5-5-10-10-10-10-10-5-1050-10-50555-50-500-1-2-3-4-5-5-5-100-10-5-10-10-100-10-51505-10-50105-10-10Time (hrs) RE: Current Time = 05-1015-10-50-10100-10-5-50-10-10-10-10-10-105101055-1050-5-60 20 40 60 80 100 120 140Distance (sm) along I-75 in Georgia from S of Forsyth through Atlanta to N of Calhoun

10090908070Hydroplaning Speed in MPH170G- 20 US-41I- 85 I- 85G-120G- 20I-675I-285 I- 20 I-285I-575G-1409080909080807070707010060801001009080907080801006090807080 9010010010080809090908090100706070907010090708010010090809010090100707010050607080Time (hrs) RE: Current Time = 080808090709080607090907070 600-1-2-3-45070807070609090100608070100100100-59040 50 60 70 80 90 100 110 120 130-660Distance (sm) along I-75 in Georgia from S of Forsyth through Atlanta to N of Calhoun5040Hydroplaning Speed (mph)17

Example: Crash in Fog and Smoke – Polk City, FloridaEvent Record Details> Event: Dense Fog Date:09 Jan 2008, 04:00:00 - 09:00:00 AM ESTFatalities: 5 Injuries: 38 Zones affected:> Description:A controlled burn from the previous afternoon was still producingsmoke as patches of dense fog began to develop around 4AM. Thesmoke and fog interacted to produce super-fog along a 2 mile areaencompassing Interstate 4 near Polk City between US 27 and thePolk Parkway. The super-fog caused zero visibility for motorists andthe result was a 70 vehicle pileup with 5 fatalities and 38injuries.High pressure in place across the area allowed for moist lowlevels and light winds overnight.18

Aftermath of Eventhttp://media.tbo.com/photos/trib/2008/feb/20508i-4file.jpg19

Fog and Smoke Area, I-4, Polk City FL20

RUC Products – Visibility

RUC Products – Temperature; Winds; Humidity

Needs/Decisions> Effective human-machine interface> Best ways to deliver weather content to drivers> Telematics/navigation devices capable ofcombining & displaying vehicle position anddriver/traffic-relevant weather information> Central source of traffic data, camera imagery &other attributes - responsible agents> Institutional cooperation & coordination> Resolution of Jurisdictional issues> Roles of public and private sectors23

Sample Users> National Weather Service WFO> Dept of Forestry> Fish and Wildlife Conservation Commission> Dept of Transportation> OEM> Drivers> Dispatchers> Police and Fire> Local media24

Societal Benefits of Transportation Weather Informatics> Safety> Efficiency> Return on investment> Helps other sectors of the economy> Real-time decision making> Short-term and long-term planning25

Summary> Necessary pieces are essentially there– Confluence of radar, surface stations, satellite, hi-resmodels, navigation devices, wireless networks, smartvehicles, traffic information telematics =“Transportation Weather Informatics”– High resolution (time and space) measurements andforecasting of weather are very good, operationallyavailable and getting better– Caveats exist such as occurrences of False Alarms> Benefits – safety, efficiency, public trust> Need private sector to set up and maintain the network26

ReferencesBenjamin, S. et al. 2007. “The RTMA Background – Hourly Downscaling ofRUC Data to 5-KM Detail.” Presented at the Annual Meetings of theAmerican Meteorological Society. Session P1.11, San Antonio, TX.JanuaryBlack, G.W. 2000. “Pavement Surface Water Phenomena and TrafficSafety.” Institute of Traffic Engineers, ITE Journal.http://findarticles.com/p/articles/mi_qa3734/is_200002/ai_n8889175Huebner, R. S. 1997. “PAVDRN Computer Model for Predicting Water FilmThickness and Potential for hydroplaning on New and ReconditionedPavements,” Transportation Research Record 1599, Paper No. 970889,128-131.Mischler, G. 2003. “Lighting Design Knowledgebase,” Lighting Glossary,Glare. http://www.schorsch.com/kbase/glossary/glare.htmlNational Transportation Safety Board (NTSB). 1980. “NationalTransportation Safety Board Special Study: Fatal Highway Accidents onWet Pavement,” Rept. NTSB-HSS-80-1, NTSB Bureau of Technology,Washington, DC.Perel, Michael, et al. 2005. “Motor Vehicle Forward Lighting.” SAETechnical Paper Series. Working Paper GTR-gtr-8-6, June.http://www.unece.org/trans/doc/2005/wp29gre/gtr8-6e.pdfPetty, K. and W Mahoney. 2007. “Weather Applications and ProductsEnabled Through Vehicle Infrastructure Integration (VII): Feasibility andConcept Development Study.” Prepared for U.S. Department ofTransportation, Intelligent Transportation Systems Joint Program Office.http://ops.fhwa.dot.gov/publications/viirpt/viirpt.pdfPisano, P. et al. 2008. “A New Paradigm for Observing the Near Surfaceand Pavement: Clarus and Vehicle Infrastructure Integration.”Transportation Research Circular Number E-C126. June.Rossetti, M. and M.Johnsen. 2008. “Impacts of Weather and Climate onCommercial Motor Vehicles”. Presented at the Annual Meetings of theAmerican Meteorological Society. Session 4B.4, New Orleans, LA.January 24Rossetti, M.A. 2002. “Implementing Successful Public-Private PartnershipsIn Transportation, Studies Involving Weather And Its Effect OnTransportation.” U.S. Department of Transportation, Volpe Center.February.Rubino, M, A. et al. 1994. “Discomfort Glare Indices: A Comparative Study,”Applied Optics, 33, 8001-8013.Seliga, .T.A. 1997. “The NEXRAD Radar System: A New Tool for HighwayTraffic Management.” Seattle, WA: University of Washington. March.http://www.transnow.org/publication/final-reports/documents/TNW97-06.pdfSeliga, T. A. and K. D. Nguyen. 1996. “The NEXRAD Radar System: A NewTool for Highway Traffic Management and Research,” Sixth AnnualMeeting and Exposition, Intelligent Transportation Society of America,April 15-18, Houston, Texas.Seliga, T. A. and L. L. Wilson. 1995. “Applications of the NEXRAD RadarSystem for Highway Traffic Management,” Preprints, 27th Conference onRadar Meteorology, Vail, CO, AMS, Boston, MA, Oct. 9-13, 176-178.Stern, A., et al. 2003. “Analysis of Weather Impacts on Traffic Flow inMetropolitan Washington DC.” Presented at Annual Meetings of theAmerican Meteorological Society, Session 10.3 January.http://ams.confex.com/ams/annual2003/techprogram/paper_54865.htmState of New Jersey Department of Transportation. 2007. “Roadway DesignManual.”http://www.state.nj.us/transportation/eng/documents/RDME/sect5E2001.shtm

References (cont.)U.S. Department of Commerce (DOC), National Oceanic andAtmospheric Administration (NOAA), Office of the FederalCoordinator for Meteorology (OFCM). 2002. “Weather Informationfor Surface Transportation. National Needs Assessment Report.”http://www.ofcm.gov/wist_report/pdf/20-appe.pdfU.S. Department of Transportation (DOT), Federal HighwayAdministration (FHWA). 1994. “Roadway Delineation Practices.”August. http://safety.fhwa.dot.gov/PED_BIKE/docs/rdwydelin.pdfU.S. Department of Transportation (DOT), Federal HighwayAdministration (FHWA). 2005. “Road Weather Information SystemEnvironmental Sensor Station Siting Guidelines.” April.http://www.ops.fhwa.dot.gov/publications/ess05/ess05.pdf

Thank you for your attention.seliga@volpe.dot.govrossetti@volpe.dot.gov