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SITE AVERAGED GRAVIMETRIC SOIL MOISTURE: 1987 (BETTS)
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Site Averaged Gravimetric Soil Moisture: 1987 (Betts)

Summary:

The Site Averaged Gravimetric Soil Moisture Data: 1987 (Betts) data set contains the site-averaged product data collected during the 1987-1989 FIFE experiment. Samples were averaged for each site, then averaged for each day. This data set includes only 1987 data.

Table of Contents:

  1. Data Set Overview
  2. Investigator(s)
  3. Theory of Measurements
  4. Equipment
  5. Data Acquisition Methods
  6. Observations
  7. Data Description
  8. Data Organization
  9. Data Manipulations
  10. Errors
  11. Notes
  12. Application of the Data Set
  13. Future Modifications and Plans
  14. Software
  15. Data Access
  16. Output Products and Availability
  17. References
  18. Glossary of Terms
  19. List of Acronyms
  20. Document Information

1. Data Set Overview:

Data Set Identification:

SITE AVERAGED GRAVIMETRIC SOIL MOISTURE: 1987 (BETTS).

Data Set Introduction:

This data set is a site-averaged product of the gravimetric soil moisture data collected during the 1987-1989 FIFE experiment. Samples were averaged for each site, and then each site was interpolated to give a value for each day. Then the sites were averaged for each day.

Objective/Purpose:

Information not available.

Summary of Parameters:

Heat flux, soil heat budget, and soil heat flux.

Discussion:

Samples were averaged for each site,then each site was interpolated to give a value for each day. Then the sites were averaged for each day. The soil moisture site averages values are at 2.5cm for the 0-5cm layer, and 7.5cm for the 5-10cm layer.

Multiplying them by a mean bulk density of 1.1 gives a representative volumetric soil moisture. Note that in papers prior to Betts and Ball 1997 (see Appendix) (Betts et al 1993, Betts and Ball 1995), an incorrect volumetric conversion was used.

The values in this data set are a profile down to 200 cm if the tube went that deep (i.e., no rock). This data was retrieved directly from the Oak Ridge DAAC. All the originating data, however, should correspond to that on CD-ROM Volume 1, dated May 22, 1994, in directory soilmstr\sm_grav.

Related Data Sets:

2. Investigator(s):

Investigator(s) Name and Title:

Alan K. Betts and John H. Ball
Atmospheric Research
Telephone: (802) 483-2087
Fax: (802) 483-6167
Email: akbetts@aol.com

Title of Investigation:

FIFE Follow-On.

Contact Information:

ORNL DAAC User Services Office
Oak Ridge National Laboratory
Telephone: 1-(865)-241-3952
Fax: 1-(865)-574-4665
Email: ornldaac@ornl.gov

Requested Form of Acknowledgment.

You may use these files freely. Please send Alan Betts (akbetts@aol.com) an e-mail if you do, so he can notify you of any updates. Please notify both Alan Betts and the ORNL DAAC of any errors you find.

This data processing was supported by NASA under Contract NAS5-32356 to Alan Betts, and an acknowledgment of the years of work that went into the production of these files would be appreciated in publications based substantially on them.

The FIFE CD-ROM can be cited as D. E. Strebel, D. R. Landis, K. F. Huemmrich, and B. W. Meeson (1994), Collected Data of The First ISLSCP Field Experiment, Vol. 1: Surface Observations and Non-Image Data Sets.

3. Theory of Measurements:

Information not available.

4. Equipment:

Sensor/Instrument Description:

ANALYSIS: The process of an individual examining the information collected during a scientific investigation. Often this takes the form of reviewing and working with output from modeling activities to give meaning to the information.

Collection Environment:

Ground-based.

Source/Platform:

Field Investigation.

Source/Platform Mission Objectives:

Information not available.

Key Variables:

Information not available.

Principles of Operation:

Information not available.

Sensor/Instrument Measurement Geometry:

Information not available.

Manufacturer of Sensor/Instrument:

Information not available.

Calibration:

Information not available.

5. Data Acquisition Methods:

Information not available.

6. Observations:

Information not available.

7. Data Description:

Spatial Characteristics:

Spatial Coverage:

The center of the FIFE 15x15 km site is close to 39.05þN, 96.53þW.

Spatial Coverage Map:

Not available.

Spatial Resolution:

These are point data.

Projection:

Information not available.

Grid Description:

Information not available.

Temporal Characteristics:

Temporal Coverage:

This data set is a time series of daily values for the period between May 20, 1987- Nov 6, 1987.

Temporal Coverage Map:

Not available.

Temporal Resolution:

Time index is Julian day.

Data Characteristics:

Parameter/Variable:

  • Soil Moisture,

Variable Description/Definition:

  • Soil Moisture:

Table 1. contains a summary of the variables in this data set. 

Table 1. Variable Description

Variable Name  Long Name               SAS Type  Description

1  Jul_Date                            8         "Julian date (day of year 
1-366)"
2  SM25                                8         "Average % soil moisture at 
0-5 cm depth"
3  SM25_k                              8         "Number of sites included in 
average soil moisture at 0-5 
cm depth (SM25)"
4  SM25_sum                            8         "Sum of soil moisture 
measurements at 0-5 cm depth"
5  SM75                                8         "Average % soil moisture at 
5-10 cm depth"
6  SM75_k                              8         "Number of sites included in 
average soil moisture at 
5-10 cm depth (SM25)"
7  SM75_sum                            8         "Sum of soil moisture 
measurements at 5-10 cm depth"
8  obs_date                            8         "Observation date (mm/dd/yyyy)"

Unit of Measurement:

Refer to Table 1.

Data Source:

Meteorological Station.

Data Range:

Information not available.

Sample Data Record:

Jul_Date, SM25,  SM25_k, SM25_sum, SM75,   SM75_k, SM75_sum, obs_date

140,      28.1,   20,      44,     26.02,   20,      44,     05/20/1987
141,      29.01,  20,      .,      26.22,   20,      .,      05/21/1987
142,      29.91,  20,      .,      26.43,   20,      .,      05/22/1987
143,      30.82,  20,      .,      26.63,   20,      .,      05/23/1987
144,      31.72,  20,      .,      26.83,   20,      .,      05/24/1987
145,      32.63,  20,      .,      27.03,   20,      .,      05/25/1987
146,      33.53,  20,      86,      27.23,  20,      85,     05/26/1987

8. Data Organization:

Data Granularity:

         File names          size (bytes) 
         ffogrv87.dat        7000

Data Format:

This data set is a time series of daily values for the period between May 20, 1987- Nov 6, 1987.

The data fields are as follows:

Day, SM25, SM25-k, SM25-sum, SM75, SM75-k, SM75-sum

Where SM25 and SM75 are gravimetric percent soil moisture for soil layers 0-5,5-10 cm.

Samples were averaged for each site, and then each site was interpolated to give a value for each day. Then the sites were averaged for each day. Fields SM25-k, SM75-k is a count of the sites in the average. SM25-sum, SM75-sum is the sum of the total number of independent measurements on that day. Thus when SM25-sum is blank, there were no measurements on that day at all. The value is pure interpolation, and attention should be paid to the rainfall data before using.

9. Data Manipulations:

Information not available.

10. Errors:

Sources of Error:

Information not available.

Quality Assessment:

Data Validation by Source:

Information not available.

Confidence Level/Accuracy Judgment:

Irregularity of sampling is the biggest problem with the soil moisture data. During dry spells and between IFC's sampling was less frequent, and this smoothes the time series considerably.

Measurement Error for Parameters:

Information not available.

Additional Quality Assessments:

Information not available.

Data Verification by Data Center:

Information not available.

11. Notes:

Limitations of the Data:

Not available.

Known Problems with the Data:

Information not available.

Usage Guidance:

Information not available.

Any Other Relevant Information about the Study:

Information not available.

12. Application of the Data Set:

Information not available.

13. Future Modifications and Plans:

There are no plans to revisit this data; but let us know of errors.

14. Software:

Information not available.

15. Data Access:

Contact Information:

ORNL DAAC User Services
Oak Ridge National Laboratory
Telephone: (865) 241-3952
FAX: (865) 574-4665
Email: ornldaac@ornl.gov

Data Center Identification:

ORNL Distributed Active Archive Center
Oak Ridge National Laboratory
Telephone: (865) 241-3952
FAX: (865) 574-4665
Email: ornldaac@ornl.gov

Procedures for Obtaining Data:

Users may place requests by telephone, electronic mail, or FAX. Data is also available via the World Wide Web at http://daac.ornl.gov.

Data Center Status/Plans:

FIFE data are available from the ORNL DAAC. Please contact the ORNL DAAC User Services Office for the most current information about these data.

16. Output Products and Availability:

This data set is available online via the World Wide Web at http://daac.ornl.gov/, or telnet ornlims.ornl.gov 6493 (128.219.24.108 6493), or eosims.ornl.gov 12345 (128.219.24.108 12345)

17. References:

Betts and Ball, 1997: FIFE surface climate and site-average data set 1987-1989, J. Atmos. Sci. In press (3rd FIFE special issue)

Betts, A.K., J.H. Ball, and A.C.M. Beljaars, 1993: Comparison between the land surface response of the European Centre model and the FIFE-1987 data. Q.J.R.M.S., 119, 975-1001.

Betts, A.K. and J.H. Ball, 1994: Budget analysis of FIFE-1987 sonde data. J.G.R., 99, 3655-3666.

Betts, A.K. and J.H. Ball, 1995: The FIFE surface diurnal cycle climate. J.G.R. 100, 25679-25693.

Betts A. K. And J. H. Ball, 1997: FIFE surface climate and site-average dataset: 1987-1989. (FIFE special issue 3 J.Atmos. Sci.in press)

Strebel, D. E., D. R. Landis, K. F. Huemmrich, and B. W. Meeson, 1994: Collected data of the First ISLSCP Field Experiment, in Surface Observations and Non-Image Data Sets., Vol 1, CD-ROM, NASA GSFC, Greenbelt, MD 20771

The First FIFE special issue in JGR (November, 1992) contains many important refs by the PI's who collected this data

Archive/DBMS Usage Documentation.

Contact the EOS Distributed Active Archive Center (DAAC) at Oak Ridge National Laboratory (ORNL), Oak Ridge, Tennessee (see the Data Center Identification Section). Documentation about using the archive and/or online access to the data at the ORNL DAAC is not available at this revision.

18. Glossary of Terms:

A general glossary for the DAAC is located at http://cdiac.esd.ornl.gov/cdiac/glossary.html.

19. List of Acronyms:

ESD Environmental Sciences Division (Oak Ridge National Laboratory) FTP File Transfer Protocol NASA National Aeronautics and Space Administration ORNL Oak Ridge National Laboratories, Oak Ridge, Tennessee, U.S.A. URL Uniform Resource Locator

A general list of acronyms for the DAAC is available at http://daac.ornl.gov/acronyms.html.

20. Document Information:

December 4, 1996 (citation revised on October 1, 2002)

Document Review Date:

May 14, 1997

Document ID:

FIFE_FFOGRV87

Citation:

Cite this data set as follows (citation revised on October 1, 2002):

Betts, A. K. 1994. Site Averaged Gravimetric Soil Moisture: 1987 (Betts). Data set. Available on-line [http://www.daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. doi:10.3334/ORNLDAAC/96.

Document Curator:

DAAC Staff
ornldaac@ornl.gov

Document URL:

http://daac.ornl.gov