TITLE: CEOP First Half EOP-3 GAPP Oak Ridge, TN Surface Meteorology and
Radiation 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: meyers@atdd.noaa.gov
1.0 DATA SET OVERVIEW
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 Oak Ridge, Tennessee. This data
set covers the time period 1 October 2002 through 31 March 2003. Further
information about the Oak Ridge flux tower is available at the
following URL:
http://www.atdd.noaa.gov/gewex.htm
1.1 Station Information
The Oak Ridge reference site is located on the Walker Branch Watershed.
The vegetation is a deciduous forest of the eastern hardwood type. The
leaf area index varies seasonally with a maximum value of about 5. The
canopy height is 24-26 m.
The flux tower is located at 35.9583 N and 84.2916 W at an elevation of
326 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.
2.0 INSTRUMENTATION DESCRIPTION
No information is currently available on the make, model or
specifications of the instrumentation used at the Oak Ridge, TN
reference site.
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_sfc_met_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 Oak Ridge reference site data.
4.2 UCAR/JOSS Quality Control Procedures
UCAR/JOSS conducted two primary quality assurrance/control
procedures on the Oak Ridge 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 Oak Ridge reference
site data.
5.0 GAP FILLING PROCEDURES
No information is currently available on any gap filling
procedures that may have been conducted on the Oak Ridge
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 Oak Ridge reference site data.
8.0 REFERENCES
None.