CEOP Reference Site Data Set Metadata Procedures The documentation (i.e. the "Readme" file) that accompanies each CEOP Reference Site Data Set is as important as the data itself. This information permits collaborators and other analysts to become aware of the data and to understand any limitations or special characteristics of data that may impact its use elsewhere. The data set documentation should accompany all data set submissions and contain the information listed in the outline below. The following outline (and content) should be adhered to as closely as possible to make the documentation consistent across all data sets. A documentation file submission must accompany each submitted data set. TITLE: BALTEX_Sodankyla_ObservatorSiteA_20050101-20051231.sfc CONTACT(S): Timo Ryyppö timo.ryyppo@fmi.fi +358-40 5921210 Rigel Kivi rigel.kivi@fmi.fi Esko Kyrö esko.kyro@fmi.fi Finnish Meteorological Institute Arctic Research Centre Tähteläntie 62 FIN-99600 Sodankylä FINLAND Tel: +358-16-619 619 Fax: +358-16-619 623 Web: http://www.fmiarc.fmi.fi, http://www.fmi.fi 1.0 DATA SET OVERVIEW: Data file is compiled for the CEOP project under responsibility of BALTEX. See CEOP web-site for project background: http://www.ceop.net Time period covered by the data: 01.01.2005-31.12.2005 Data are measured at Sodankyla Arctic Research Centre's Observatory (Observatory Site A): Coordinates (WGS-84) lat: 67 22' 00,0" lon: 26 37' 44,6" elev: 179,2 m a.s.l, (Incoming and outgoing longwave and incoming shortwave radiation measurements are made in tower at 193,3 m height a.s.l) (PAR is measured at Observatory Site B, lat: 67 21' 42,7" lon: 26 38' 16,2" elev: 179,3 m a.s.l) Operational data (i.e. whole data set): Finnish Meteorological Institute. 2.0 INSTRUMENTATION DESCRIPTION: Station pressure: Vaisala PTB220B, 1m Air temperature: Pentronic PT100 element, 2m Dew point temperature: calculated (FMI) Relative humidity: Vaisala HMP35D, 2m Specific humidity: calculated (CEOP; http://www.eol.ucar.edu/projects/ceop/dm/documents/refdata_report/eqns.html) Wind speed: Vaisala WAA-25, 22m Wind direction: Vaisala WAV-15, 22m U wind component: calculated (CEOP; http://www.eol.ucar.edu/projects/ceop/dm/documents/refdata_report/eqns.html) V wind component: calculated (CEOP; http://www.eol.ucar.edu/projects/ceop/dm/documents/refdata_report/eqns.html) Precipitation: Vaisala FD12P, 2m Snow depth: Campbell SR50, 2m Incoming shortwave: Kipp & Zonen CM11, 14m Outgoing shortwave: Kipp & Zonen CM11, 2m Incoming longwave: Kipp & Zonen CG4, 14m Outgoing longwave: Kipp & Zonen CG4, 14m Net Radiation: calculated (CEOP; http://www.eol.ucar.edu/projects/ceop/dm/documents/refdata_report/eqns.html) Skin temperature: Not measured Incoming PAR: Kipp & Zonen PAR Lite, 2 m Outgoing PAR: Kipp & Zonen PAR Lite, 2 m 3.0 DATA COLLECTION AND PROCESSING: All the available data is measured and collected automatically. All other except LW and SW radiation values are logged with Vaisala Milos 500 weather station. LW and SW radiation measurements are made with a PC equipped with data acquisition board. All data is collected via leased network connection to FMI data center. For description of derived parameters and processing techniques used, see 2.0 INSTRUMENTATION DESCRIPTION 4.0 QUALITY CONTROL PROCEDURES Quality control procedure is standard FMI quality control, and additional complete visual checking. For more information about quality control and flagging, see contact persons. 5.0 GAP FILLING PROCEDURES No gap filling applied except for incoming PAR. Incoming PAR gap filling follows the next order: 1. Global radiation sensor at the same tower (multiplied by 2.02) 2. Global radiation sensor in 500 m distance of PPFD sensor (multiplied by 2.02) 3. Modeled using an average of previous and following value (1-2 missing), linear interpolation (about <10 missing), average diurnal cycle of closest 5 days (>10 values missing) 6.0 DATA REMARKS: Data is classified as category 1 with reference to CEOP data classification. PAR values are measured at Observatory Site B (see 1.0 DATA SET OVERVIEW for details). Station pressure, air temperature, humidity, wind parameters and snow depth are values measured twice per hour (at full hours and near half hours). Wind speed and direction values are 10 minutes avarage values. Precipitation is measured once per hour (at full hours). Radiation values are avaraged over the 30-minutes prior to the reported observation. Missing data periods flagged with "M" and corresponding data marked as "-999.99" (see: http://www.eol.ucar.edu/projects/ceop/dm/documents/refdata_report/data_flag_definitions.html). Calculated data (e.g. wind components) are flagged as a good data if the original data (from which the new parameters are derived) are good. 7.0 REFERENCE REQUIREMENTS: Finnish Meteorological Institute must be stated as data source when the data are used. 8.0 REFERENCES: