Data Set "HMET03_HOURLY_MET_PHASE1" ----------------------------------- Revised: February 7, 2001 BOREAS Follow-on HMet-3 Phase I Flux Tower Hourly Meteorology 1994-1996 Point data developed from in situ observations at four flux tower sites were combined to produce continuous, above the canopy, meteorological forcing data sets. Data from the OA and OBS sites in the SSA and the Fen and OBS sites in the NSA were used to create continuous time series with a time step of one hour, covering the period from 1-Jan-1994 through 1-Dec-1996. Meteorological variables of interest are surface air pressure, air temperature, dew point temperature, wind speed, wind direction, precipitation, incoming solar (shortwave) radiation, and incoming infrared (longwave) radiation. This data set is one among three categories of meteorological forcing data sets that have been assembled for BOREAS Hydrometeorological and Carbon Assimilation Model Intercomparison Projects as part of the BOREAS Follow-on activities. Additional meteorological forcing data sets, Phase II and III data, at study area and regional grid scales, respectively, have also been produced. Acknowledge: Bart Nijssen, Dennis P. Lettenmaier Column Name Units Column Description ----------- ----- ------------------ SITE_NAME [none] The identifier assigned to the site by BOREAS, in the format SSS-TTT-CCCCC, where SSS identifies the portion of the study area: NSA, SSA, REG, TRN, and TTT identifies the cover type for the site, 999 if unknown, and CCCCC is the identifier for site, exactly what it means will vary with site type. DATE_OBS [DD-MON-YY] The date on which the data were collected. TIME_OBS [HHMM GMT] The Greenwich Mean Time (GMT) at the beginning of the observation interval. In this data set a backward time tag convention is used (i.e., time tag n indicates data record applies to hourly period n to n+1). AIR_TEMP [degrees C] Air temperature above the canopy. VAPOR_PRESS_DEF [Pascals] Vapor pressure deficit above the canopy. U_WIND_SPEED [meters] Zonal wind speed above the canopy. [second^-1] V_WIND_SPEED [meters] Meridional wind speed above the canopy. [second^-1] PRESS [Pascals] Surface pressure. SHORT_RAD_IN [Watts] Incoming shortwave radiation above the [meters^-2] canopy. LONG_RAD_IN [Watts] Incoming longwave radiation above the canopy [meters^-2] PRECIP [millimeters] Precipitation. [hour^-1] CRTFCN_CODE [none] The BOREAS certification level of the data. Examples are CPI (Checked by PI), CGR (Certified by Group), PRE (Preliminary), and CPI-??? (CPI but questionable). REVISION_DATE [DD-MON-YY] The most recent date when the information in the referenced data base table record was revised. Data Format ----------- The data file contains numerical and character fields of varying length separated by commas. Character fields are enclosed with single apostrophe marks. There are no spaces between the fields. Each data file on the CD-ROM has four header lines of Hyper-Text Markup Language (HTML) code at the top. When viewed with a Web browser, this code displays header information (data set title, location, date, acknowledgments, etc.) and a series of HTML links to associated data files and related data sets. Line 5 of each data file is a list of the column names, and line 6 and following lines contain the actual data File Names ---------- The different types of files can be told apart by their extensions. The general form of the data file names is Date_Site_Name.csv. The Date_Site part of the name is 22 characters, the Name is 3 characters, and the '.csv' extension is 4 characters (for a total of 30 characters). The formats and meanings of the Date component are: YY-MM-DD : The file only contains data from a particular date YY-MM-00 : The file contains all days of a particular month YY-00-00 : The file contains all days of a particular year ALLDATES : The file contains data over all dates The formats and meanings of the Site component are: MULTIPLESITES : The file contains data over all sites SSS-CCC-TTTTT : The file contains data from a particular site SSS : the BOREAS study area identifier CCC : the abbreviated land cover type at the site TTTTT : the type of site The Name component is a 3-letter identifier for the data set. The '.csv' extension stands for 'comma separated values'.