TITLE: CEOP EOP-3 and EOP-4 GAPP Bondville, IL Surface Meteorology and 
       Radiation Data Set


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


This data set contains 30-minute resolution surface meteorology and
radiation 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: 

1.1  Station Information

The Bondville reference site is located near Champaign, IL on Reifsteck
Farm.  The vegetation alternates between corn and soybeans crops.

Latitude: 40.00621 N
Longitude: 88.29041 W
Elevation: 216 m

This data set includes observations of air temperature, dew point,
relative humidity, specific humidity, wind speed, wind direction, U wind
component, V wind component, station pressure, precipitation, skin
temperature, incoming PAR, incoming longwave, incoming shortwave,
outgoing PAR, outgoing longwave, outgoing shortwave, and net radition.

This station does not provide measurements of snow depth.


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


3.1  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 

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:



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.


The net radiation parameter had two values gap filled during
this period.  No information is currently available on the gap
filling procedures that were conducted on the Bondville reference 
site data.


No data remarks.


No information is currently available on any reference requirements
for the Bondville reference site data.