TITLE: Mesonet FSL MADIS Data [JOSS] CONTACTS: Steve Williams UCAR/JOSS P.O. Box 3000 Boulder CO 80307-3000 email: sfw@ucar.edu phone: 303-497-8987 1.0 DATA SET OVERVIEW This data set contains meteorological data from the Forecast Systems Lab (FSL) Meteorological Assimilation Data Ingest System (MADIS) during the IHOP period. Data cover the period from 1 May to 30 June 2002. The data are in netCDF format. 2.0 INSTRUMENT DESCRIPTION 2.1 Instrumentation No Information. 2.2 Networks Included The following networks are represented in this dataset. APG APRSWXNET AWX FL-Meso GLDNWS GPSMET HADS IADOT INTERNET KSDOT MNDOT MesoWest NOS-PORTS RAWS UDFCD WXforYou 3.0 DATA COLLECTION AND PROCESSING UCAR/JOSS conducted no processing or quality control on these data. 4.0 DATA FORMAT AND FILE NAMING 4.1 Data Format These data are in network Common Data Form (netCDF) format. For information on netCDF see: http://www.unidata.ucar.edu/packages/netcdf/ The files are delivered gzipped. Some of the variables present in this dataset, and the units follow. (Taken from the netCDF header. For a complete list refer to the netCDF header.) temperature: "temperature" temperature:units = "kelvin" tempChangeTime: "temperature time of last change" dewpoint: "dew point temperature" dewpoint:units = "kelvin" relHumidity: "relative humidity" relHumidity:units = "percent" stationPressure: "station pressure" stationPressure:units = "pascal" seaLevelPressure: "sea level pressure" seaLevelPressure:units = "pascal" pressChangeChar: "character of pressure change" pressChange3Hour: "3 hour pressure change" pressChange3Hour:units = "pascal" altimeter: "altimeter setting" altimeter:units = "pascal" altimeter:_FillValue = 3.402823e+38f windDir: "wind direction" windDir:units = "degree" windSpeed: "wind speed" windSpeed:units = "meter/sec" windGust: "wind gust" windGust:units = "meter/sec" windGustChangeTime: "wind gust time of last change" windDirMax: "wind direction at gust" windDirMax:units = "degree" visibility: "visibility" visibility:units = "meter" precipAccum: "precip accumulation" precipAccum:units = "mm" precipRate: "precipitation rate" precipRate:units = "meter/second" precipType: "precipitation type" precipIntensity: "precipitation intensity" timeSinceLastPcp: "time since last precip" timeSinceLastPcp:units = "second" solarRadiation: "solar radiation" solarRadiation:units = "watt/meter2" solarRadChangeTime: "solar radiation time of last change" rawMessage: "raw text LDAD mesonet message" totalColumnPWV: "Total column precipitable water vapor" totalColumnPWV:units = "centimeters" totalSignalDelay: "Total GPS signal delay" totalSignalDelay:units = "meters" drySignalDelay: "Dry component GPS signal delay" drySignalDelay:units = "meters" wetSignalDelay: "Wet component GPS signal delay" wetSignalDelay:units = "meters" meanWeightedTemperature: "Mean weighted temperature" meanWeightedTemperature:units = "kelvin" capPi: "Wet delay mapping function" roadTemperature: "Road temperature - sensors 1, 2, 3, 4" roadTemperature:units = "kelvin" roadLiquidFreezeTemp: "Road liquid freezing temp - sensors 1, 2, 3, 4" roadLiquidFreezeTemp:units = "kelvin" roadLiquidChemFactor: "Road liquid chem factor - sensors 1, 2, 3, 4" roadLiquidChemPercent: "Road liquid chem percent - sensors 1, 2, 3, 4" roadLiquidChemPercent:units = "percent" roadLiquidIcePercent: "Road liquid ice percent - sensors 1, 2, 3, 4" roadLiquidIcePercent:units = "percent" roadLiquidDepth: "Road liquid depth - sensors 1, 2, 3, 4" roadLiquidDepth:units = "meter" roadState: "Road State - sensors 1, 2, 3, 4" roadSubsurfaceTemp: "Road subsurface temp - sensors 1, 2, 3, 4" roadSubsurfaceTemp:units = "kelvin" fuelTemperature: "Fuel temperature" fuelTemperature:units = "kelvin" fuelTempChangeTime: "fuel temperature time of last change" fuelMoisture: "Fuel moisture" fuelMoisture:units = "percent" fuelMoistChangeTime: "fuel moisture time of last change" soilTemperature: "Soil temperature" soilTemperature:units = "kelvin" soilMoisture: "Soil moisture" soilMoisture:units = "percent" 4.2 File Naming conventions yyyymmdd.tar.gz where: yyyy = year mm = month dd = day These files are gzipped tar files by day. Each tar file contains a separate netCDF format file for each hour. The names of the netCDF files within the tar file correspond to the date and time. yyyymmdd_hhmm where: yyyy = year mm = month dd = day hh = hour mm = minute 5.0 DATA REMARKS 5.1 Iowa AWOS precipitation Problem Note the following problem with precipitation observations from Iowa AWOS stations. The 1-min Iowa AWOS data are available from UCAR/JOSS for the IHOP period at: http://www.joss.ucar.edu/cgi-bin/codiac/dss?77.099 Message from Daryl Herzmann (akrherz@iastate.edu) * Program Assistant -- Iowa Environmental Mesonet * http://mesonet.agron.iastate.edu Sent 10 April 2003: Anyway, most (not all) of these stations are outfitted with tipping buckets. All of you have been receiving the AWOS precipitation amounts from the raw METARs, but up until today, there has been a fundamental flaw with the observations. The site resets the hourly precipitation counter at :55 after the hour, but METARs were only relayed at :05, :25 and :45 after the hour. This would result in 10 minutes of missing potential rainfall data every hour. The Iowa Department of Transportation sends us their 1 minute interval data archive from the network at the end of every month. While looking at this dataset, I noticed this timing problem last summer. The Des Moines WFO and the Iowa Mesonet have been working closely with the DOT to get this problem resolved. And today it has been. The Iowa AWOS sites are now reporting at :15, :35 and :55 after the hour, which eliminates the timing issue. 6.0 REFERENCES FSL/MADIS Home Page: http://www-sdd.fsl.noaa.gov/MADIS/