TITLE: CEOP EOP-3 and EOP-4 GAPP Bondville, IL Flux Data Set CONTACT: Tilden P. Meyers Atmospheric Turbulence and Diffusion Division 456 S. Illinois Ave. Oak Ridge, TN 37830 Telephone: (865) 576-1245 Fax: (865) 576-1327 E-Mail: Tilden.Meyers@noaa.gov 1.0 DATA SET OVERVIEW This data set contains 30-minute resolution flux data from the Coordinated Enhanced Observing Period (CEOP) Global Energy and Water Cycle Experiment (GEWEX) Americas Prediction Project (GAPP) Reference Site operated by Tilden Meyers (National Oceanic and Atmospheric Administration (NOAA) Atmospheric Turbulence and Diffusion Division (ATDD) at Bondville, Illinois. This data set covers the time period 1 October 2002 through 31 December 2004. Further information about the Bondville flux tower is available at the following URL: http://www.atdd.noaa.gov/gewex.htm 1.1 Site Information The Bondville reference site is located near Champaign, IL on Reifsteck Farm. The vegetation is a rotating cropland (corn/soybean). The flux measurement height is 10 m. The flux tower is located at 40.00621 N and 88.29041 W at an 216 m elevation. This data set includes observations of CO2 flux, sensible heat flux, and latent heat flux at 10.0 m height. Also included is soil heat flux at the -0.04 m height. 2.0 INSTRUMENTATION DESCRIPTION Flux Measurement Height - 10m Canopy Age - Agriculure-Corn,Soybean Canopy Height - bean:.7-1m, corn:2.6-3m Collection Period - 30 minutes Sonic - RM Young 81000V Gill R2 until 7/02 IRGA - ATDD Open-Path Air Temp - Thermometrics PRT RH - Vaisala 50Y Pressure - Vaisala PTB101B Wind Speed and Direction - RM Young 05103 Precipitation - Hydrol. Serv. TB3 Quantum - Apogee QSO Licor 190SB until 5/23/03 Surface Temp - Apogee IRTS-P Longwave Rad Incoming - Kipp&Zonen CNR1- CG3 Longwave Rad Outgoing - Kipp&Zonen CNR1- CG3 Shortwave Rad Incoming - Kipp&Zonen CNR1- CM3 Shortwave Rad Outgoing - Kipp&Zonen CNR1- CM3 Net Rad - Kipp&Zonen CNR1 Ground Heat Flux - Hukseflux HFP01SC ATDD thermopiles-2 Soil Moisture - Delta-T PR1/6 Delta-T Thetaprobes until 7/02 Soil Temperature - ATDD Probe with YSI Thermistors Wetness - Campbell Sci 237 3.0 DATA COLLECTION AND PROCESSING 3.1 NOAA/ATDD Data Collection and Processing Main computer: Shuttle SpaceWalker Mini-Barebones System with 250 MB Internal Zip Disk. This is a neat computer box, measuring 270 mm x 190 mm x 170 mm. It provides a VIA chipset and supports Intel PIII/Celeron/VIA C3 processors. It has two PC133 memory slots, an onboard 2D/3D graphics engine, two onboard IEEE 1394 ports (FireWire), four Universal Serial Bus (USB) ports, one onboard 10/100 MB LAN port, and one onboard AC '97 audio interface. It also includes S-video and TV-out jacks, two 3.5" drive bays, one 5.25 inch drive bay, and one PCI slot which utilizes a riser card. Serial Interface: Keyspan USB 4-port serial adapter. This provides four RS-232 serial ports in an easily expandable box. The com port connections are described below: Com 1 - RM Young ultrasonic anemometer. The sonic provides 10 Hz U, V, W winds and air temperature. In addition, an ATDD IRGA is used to measure CO2 and H2O concentrations through the sonic anemometer's built-in A/D system. Com 2 - Campbell Scientific CR10/23X Data Logger. The data logger collects up to 15 channels of analog data and stores at 1 Hz. All data collected by the data logger are downloaded to the Linux computer once per day. Typical data measured include soil moisture and temperature, mean wind speed and direction from an RM Young propeller anemometer, rainfall data, solar radiation, and air pressure and temperature. Com 3 - Olympus Camedia digital camera. This camera provides images of the site once per hour from 8:00 am until 6:00 pm. These images are archived on the 250MB removable Zip disk. Com 4 - Motorola Cell-Modem back phone. The cellular phone modem is connected to Com 4 allowing remote access from a dial-up line. Routine data downloads and maintenance is performed using dial-up services provided by Kermit. The Linux software has been developed in-house. REA Applications An extended application of the GEWEX hardware and software involves the use of Relaxed Eddy Accumulation to measure fluxes of trace gases that cannot be easily measured at high frequency in real-time (e.g. Mercury, Methane, Sulfur, etc). The software control for the REA system is quite unique and simple. The control of the up, mid, and down sampling valves is performed using the RS-232 control lines CTS (Clear-To-Send) and DTR (Data-Terminal-Ready). By toggling these two lines high and low, four combinations can be obtained. This is easily accomplished in software and conveniently uses the vertical winds measured from the sonic anemometer. 3.2 UCAR/JOSS Data Processing The University Corporation for Atmospheric Research/Joint Offfice for Science Support (UCAR/JOSS) converted the data from the raw format provided by NOAA/ATDD into the CEOP EOP-3 data format agreed to by the CEOP Scientific Steering Committee. This format is described in detail as part of the CEOP Reference Site Data Set Procedures Report which is available at the following URL: http://www.joss.ucar.edu/ghp/ceopdm/refdata_report/ceop_flux_format.html 4.0 QUALITY CONTROL PROCEDURES 4.1 NOAA/ATDD Quality Control Procedures No information is currently available on the NOAA/ATDD quality control procedures conducted on the Bondville reference site data. 4.2 UCAR/JOSS Quality Control Procedures UCAR/JOSS conducted two primary quality assurrance/control procedures on the Bondville reference site data. First the data has been evaluated by a detailed QA algorithm that verifies the format is correct, examines any QC flags, and conducts basic checks on data values. Second, JOSS conducts a manual inspection of time series plots of each parameter. UCAR/JOSS did not apply any QC flags to the Bondville reference site data. 5.0 GAP FILLING PROCEDURES All parameters included in this data set have had some values gap filled. No information is currently available on any gap filling procedures conducted on the Bondville reference site data. 6.0 DATA REMARKS No data remarks. 7.0 REFERENCE REQUIREMENTS No information is currently available on any reference requirements for the Bondville reference site data. 8.0 REFERENCES None.