The Washington State Ferry System (WSF) is the largest ferrysystem in the United States. The 29-vessel fleet makes over500 trips per day, facilitating transportation ofcommuters, tourists, vehicles, and goods to islands and peninsulasthroughout Puget Sound. Weather systems in the area move from thePacific Ocean across western Washington, with wind speedand direction on the waters of Puget Sound being influenced bythe Olympic and Cascade mountain ranges. Surface winds areoften deflected or funneled contrary to the barometric flow of thesystems. Personal observations of pilots, Washington State Ferrycaptains, and other mariners have shown weather conditions on theSound to be vastly different, at times, from those being recordedby National Oceanic and Atmospheric Administration(NOAA) shore side sensors, and by four buoy stations in the areaoperated by the National Weather Service. In an effort to makemeteorological data from the Sound available to the public, theWashington State Department of Transportation funded theinstallation of weather stations on seven of the ferries. Thestations mea-sure meteorological parameters along the ferry routesand provide ferry operators and the general public with data formore accurate weather reports and forecasts. The stationsprovide meteorological data where such data was previouslyunavailable due, in part, to the unique geographic andenvironmental features of the region. In 1995,The Universityof Washington, School of Marine Affairs established the SmartForum, instituting a means for federal, state, and local regulatorsto exchange information with marine operators, managers and thegeneral public about safe marine transportation in PugetSound. The involvement of Campbell Scientific, Inc., inplacing weather stations on the ferries, was a direct result of theSmart Forum. The weather stations were integrated into the alreadyexisting Fleet Location System (FLS),a real-time ferrytracking system used by the WFS to maintain the exact locations ofeach ferry and coordinate scheduling. MeteorCommunications Corporation (MCC) provided the FLS with CampbellScientific equipment and in turn integrated the weather stationsinto the FLS systems of the ferries. Each station consists of aCR10X data-logger which measures air temperature, barometricpressure, relative humidity, and wind speed and directionsensors. A Global Positioning System (GPS) pro-vides globalposition coordinates, vessel speed over ground and courseover ground. A gyrocompass (GYRO) pro-vides the actual vesselheading. Data from the GPS,GYRO and CR10X are input to aMCC-545A RF modem, which corrects the measured wind speedand direction using the vessel speed, heading and course overground. The RF modem outputs the corrected wind speedand direction back to the CR10X for display on the panel, thentransmits a data report. The data are displayed to the ferrycaptain on the vessel itself through use of an LED display panelinterfaced to the CR10X.Data are also delivered to aWashington State Ferry work station, and are available fordissemination to the NWS and the University of Washington, inaddition to being posted to the Washington State Ferry web page forpublic use. During periods of high winds and maximum tidalcurrents, some ferries are pre-vented from safely landing at, ordeparting from, their terminal slips. With a single delaycausing dramatic concern for thousands of commuters, theinstallation of weather stations on some ferries and transmissionof the subsequent real-time data fills a critical gap in theever-changing puzzle that is Puget Sound weather.
The Washington State Department of Transportation, inconjunction with the University of Washington, posts data from theferries on its web site (see address above)in near real-time. Arrows indicate wind direction and speed (in knots).
The content of this Application-at-a-Glance was obtained (withpermission)from the following sources. The reader is referredto these documents for a more complete discussion of theapplication and the methods used: Richard J.Fulthorp, BSEE, Meteor Communications Corporation,(MCC)Software Engineering,“ Washington State Ferry Mobile WeatherStation.” Copyright January,2000.Joseph Nortz, Washington StateFerries, and Jay Creech, Meteor Communications Corporation,“ PugetSound Wind Speed Data Collection System.” Copyright August,1999.