Daily Climate Data for the Walker Branch
Throughfall Displacement Experiment

1.1 Document Title: TDE Daily Climate Data
1.2 Revision Date:  30 April 2007
1.3 Document Summary:  Daily climate variables from the TDE site for 1993 through 2006.
1.4 Sponsor: Office of Biological and Environmental Research, U. S. DOE

2.1 Investigator and data set contact:

P.J. Hanson (hansonpj@ornl.gov)
Research Staff Member
Environmental Sciences Division
Oak Ridge National Laboratory
P.O. Box 2008
Oak Ridge, TN 37830-6038
2.2 Title Of Investigation:
Walker Branch Throughfall Displacement Experiment (TDE)

Daily integrated or averaged values for incident photosynthetically active radiation, incident total radiation, air temperature, relative humidity, rainfall, and soil temperature at  10-15 cm.

Measurements of incoming rainfall, irradiance (Pyranometer sensor, LiCor Inc.) and photosynthetic photon flux density (Quantum sensor, LiCor Inc.) were obtained in a nearby clearing until 1998 when above canopy observations were added to the ambient plot tower. Clearing data were used to represent "above-canopy" conditions for the experimental site for the years 1993-1997. Two tipping bucket rain gauges with 3 m extension troughs attached are installed on each plot to evaluate the amount of throughfall reaching the forest floor. Sub-canopy air temperatures (2 stations per treatment plot) are made at approximately 1 m of height in a location shielded from direct solar radiation. Soil temperatures are measured at two depths (15 and 35 cm) and 4 locations per plot. All temperatures are measured with thermistors. Climate data are collected as hourly means and logged on data loggers (Li-1000, LiCor Inc.) housed in instrument enclosures located at one upslope and one downslope location per treatment plot, and one enclosure in the nearby clearing.



Data are provided in comma delimeted text files where the first line includes the variable names and subsequent lines include the following data by month.

6.1 Variable, Definition, and Units

6.2 Number of Records: 5113 days
6.3 Missing data: There are no missing data in these files.
6.4 Related Data Sets: Daily and hourly data for 1993, 1994, 1995, 1996, 1997,1998,1999, 2000, 2001, 2002, 2003, 2004, 2005 and 2006 are also available.

These daily data and the original hourly data from which they were derived have been checked for errors and missing data. If bad or missing data were found approximate replacement data were obtained from other weather data sources in the area.

8.1 Limitations of the data:     None.
8.2 Known Problems With The Data:     None.
8.3 Usage Guidance:     None.


Hanson PJ, Todd DE, Huston MA (2003) Walker Branch Throughfall Displacement Experiment (TDE) In: Hanson PJ, Wullschleger SD, Eds, North American Temperate Deciduous Forest Responses to Changing Precipitation Regimes. Springer, New York, pp. 8-31.

Hanson, P.J. , D.E.Todd and J.S. Amthor. 2001. A six year study of sapling and large-tree growth and mortality responses to natural and induced variability in precipitation and throughfall.   Tree Physiology 21: 345-358.

Hanson P.J. 2000.  Large-scale Water Manipulations -- chapter 23 In: O.E. Sala, R.B. Jackson, H.A. Mooney, and R.W. Howarth, eds.  Methods in Ecosystem Science, Springer-Verlag, New York.  pp. 341-352.

Hanson, P.J., D.E. Todd, N.T. Edwards, and M.A. Huston.  1995.  Field performance of the Walker Branch Throughfall Displacement Experiment,   In:  A. Jenkins, R.C. Ferrier, and C. Kirby, eds., Ecosystem Manipulation Experiments: scientific approaches, experimental design and relevant results, Ecosystem Research Report #20, Commission of the European Communities, pp. 307-313.

Hanson, P.J., D.E. Todd, M.A. Huston, J.D. Joslin, Jennifer Croker, and R. M. Augé. 1998.  Description and field performance of the Walker Branch Throughfall Displacement Experiment: 1993-1996, ORNL/TM-13586, Oak Ridge National Laboratory, Oak Ridge, Tennessee.


Click on the following to view data for the listed year.
Once open the files can exported as text files with the 'Save As' command.

Daily data for 1993
Daily data for 1994
Daily data for 1995
Daily data for 1996
Daily data for 1997
Daily data for 1998
Daily data for 1999
Daily data for 2000
Daily data for 2001
Daily data for 2002
Daily data for 2003
Daily data for 2003 with modified quantum data 30 Apr 2007
Daily data for 2004
Daily data for 2004 with modified quantum data 30 Apr 2007
Daily data for 2005
Daily data for 2005 with modified quantum data 30 Apr 2007
Daily data for 2006