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ATMOS. PROFILE: RADIOSONDE - NCDC (FIFE)
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Atmos. Profile: Radiosonde - NCDC (FIFE)

Summary:

The NOAA Radiosonde Observations - 1989 (NCDC) Data Set contains radiosonde data obtained from the National Climatic Data Center (NCDC). These 396 days of data cover 13 months from October 1988 through October 1989. These data were collected using sondes released in Dodge City and Topeka Kansas, 337 km and 68 km, respectively, from the FIFE study area. Radiosonde observations were made to determine the pressure, temperature, and humidity from the surface to the point where the sounding was terminated.

It is assumed that the use of these data is applicable to the FIFE study because these meteorological data are relatively stable in the horizontal domain. These data may be used as input to numerical models, as well as verification data for simulation studies.

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:

Atmos. Profile: Radiosonde - NCDC (FIFE)
(NOAA Radiosonde Observations - 1989 (NCDC)).

Data Set Introduction:

The NOAA Radiosonde Observations - 1989 (NCDC) Data Set contains atmospheric pressure, geopotential height, atmospheric temperature, relative humidity, wind direction, and wind speed radiosonde data obtained from the National Climatic Data Center (NCDC). These data cover for 13 months from October 1988 through October 1989. There are 396 days of data during this period with data at 12 hour intervals.

Objective/Purpose:

The FIFE Staff Science effort covered those activities which were FIFE community level activities, or required uniform data collection procedures across sites and time. These activities included the acquisition, processing and archiving of meteorological parameters of the atmosphere above the FIFE site. These data may be used as input to numerical models, as well as verification data for simulation studies.

Summary of Parameters:

Atmospheric pressure, geopotential height, atmospheric temperature, relative humidity, wind direction, wind speed.

Discussion:

The radiosonde data was obtained from the National Climatic Data Center (NCDC). These data are available for 13 months from October 1988 through October 1989. There are 396 days of data during this period with data at 12 hour intervals. Unlike the radiosonde data collected at the FIFE study area (see the FIFE Radiosonde Data (Brutsaert)) these data were collected using sondes released in Dodge City and Topeka Kansas, 337 km and 68 km, respectively, from the FIFE study area.

Related Data Sets:

FIS Data Base Table Name:

NCDC_RADIOSONDE_DATA.

2. Investigator(s):

Investigator(s) Name and Title:

Staff science.

Title of Investigation:

Staff Science Meteorological Data Acquisition Program.

Contact Information:

Contact 1:
Dr. Robert J. Lutz
Hughes STX Corp.
301-286-1272

Contact 2:
U.S. Department of Commerce
NOAA/NESDIS
704-259-0682

Requested Form of Acknowledgment.

The NOAA Radiosonde Observations - 1989 (NCDC) was obtained by FIS from NOAA's National Climatic Data Center. The data and documentation were interpreted and put into FIFE formats by Dr. Robert J. Lutz of Hughes STX Corporation. His work is greatly appreciated.

3. Theory of Measurements:

Radiosonde observations are made to determine the pressure, temperature, and humidity from the surface to the point where the sounding is terminated. It is assumed that the use of these data is applicable to the FIFE study because these meteorological data are relatively stable in the horizontal domain.

4. Equipment:

Sensor/Instrument Description:

The radiosonde is a balloon-borne, battery-powered instrument used together with the ground-receiving equipment to delineate the vertical profile of the atmosphere. The radiosonde consists of meteorological measuring elements coupled to a radio transmitter and assembled into a small lightweight box. The device is carried aloft by a balloon filled with hydrogen, natural gas, or helium gas. Included in the train is a small parachute to slow the descent of the instrument after the balloon bursts, thereby minimizing the danger of injury to life and property.

Collection Environment:

Airborne.

Source/Platform:

Balloon filled with hydrogen.

Source/Platform Mission Objectives:

To measure pressure, temperature, and humidity profiles in the atmosphere.

Key Variables:

Pressure, height, temperature, and relative humidity.

Principles of Operation:

Pressure is measured by means of a baroswitch which employs an expanding aneroid pressure cell to move a contact arm across a commutator bar as the pressure decreases. Temperature is measured by a thermistor. The electrical resistance of the thermistor is a function of temperature. Relative humidity is measured by a hygristor, whose electrical resistance is a function of the relative humidity and to some extent, temperature.

As the radiosonde ascends, the thermistor and hygristor are switched sequentially into the modulator circuit by the baroswitch. The amplitude of the received signal, therefore, is alternately a function of temperature or humidity. Because of the translation from amplitude to frequency done by the modulation circuit the signal may be any value from 0 to 200 Hz. Periodically, the thermistor and hygristor are bypassed in the modulator circuit. Reference circuits using fixed resistors are then used to modulate the carrier frequency to known values, 95, 190, or 195 Hz (47.5, 95, or 97.5 recorder divisions). Any changes that may be occurring in the modulator circuit can then be evaluated.

Sensor/Instrument Measurement Geometry:

The radiosonde consists of meteorological measuring elements coupled to a radio transmitter and assembled into a small lightweight box.

Manufacturer of Sensor/Instrument:

Not available at this revision.

Calibration:

Specifications:

Not available at this revision.

Tolerance:

Not available at this revision.

Frequency of Calibration:

Calibration is performed at the beginning of each sounding.

Other Calibration Information:

Calibration charts are provided by the manufacturer of the radiosonde. The serial numbers affixed to the baroswitch assembly are checked to make sure that they agree with those printed on the calibration chart and on the instrument. If the baroswitch numbers disagree, the radiosonde is rejected.

5. Data Acquisition Methods:

The radiosonde transmits meteorological information consisting of pressure obtained from an aneroid cell, temperature, and relative humidity. The telemetered meteorological information from the radiosonde is detected, amplified, and shaped by a receiver, and the processed information is printed in graphic form on a strip chart recorder or stored on computer disc. These discs were then transcribed to magnetic tape and archived at the National Climatic Data Center (NCDC).

FIS staff obtained these data on tape from the NCDC. FIS staff read the tapes, using documentation that was produced by the NCDC.

6. Observations:

None.

7. Data Description:

Spatial Characteristics:

Spatial Coverage:

NOAA radiosonde data were collected from two stations in Kansas. The names, locations, and approximate distance from the FIFE site are listed below.

UTM UTM

LOCATION        NORTHING  EASTING  LATITUDE  LONGITUDE  DISTANCE
--------------  --------  -------  --------  ---------  --------
Dodge City, KS  4180534   414568   37 46 12  99 58 12    337 km
Topeka, KS      4327629   272466   39 04 12  95 37 48     68 km

The FIFE STATION_ID and SITEGRID_ID for these locations are:

STATION_ID            SITEGRID_ID
-----------------   ------------------
451                    XRSD-RDN
456                    XRST-RDN

The horizontal coverage of an individual sonde varies depending upon the track the sonde takes as it ascends. The data were collected 400 km apart.

Spatial Coverage Map:

Not available.

Spatial Resolution:

The horizontal resolution varies with the rate and angle of the ascent. The specific values are not available at this revision.

The vertical resolution will vary as the radiosonde ascends.

Projection:

Not available.

Grid Description:

Not available.

Temporal Characteristics:

Temporal Coverage:

The overall time period of data acquisition was from October 1, 1988 through October 31, 1989.

Temporal Coverage Map:

Not available.

Temporal Resolution:

Observations were made at least twice a day at 0000 GMT and 1200 GMT. On some days observations are available at three hour intervals (i.e. 0300, 0600, 0900, 1200, 1500, 1800, 2100 and 0000 GMT).

Data Characteristics:

The SQL definition for this table is found in the NCDC_SON.TDF file located on CD-ROM Volume 1.


Parameter/Variable Name
Parameter/Variable Description Range Units Source
SITEGRID_ID This is a FIS grid location code. Site grid codes (SSEE-III) give the south (SS) and the east (EE) cell number in a 100 x 100 array of 200 m square cells. The last 3 characters (III) are an instrument identifier.
STATION_ID The FIS site identifier used to designate this site.
OBS_DATE The date of the observations, in the format DD-mmm-YY.
OBS_TIME The time that the observation was [GMT] taken in GMT. The format is (HHMM).
ATMOSPHERIC_PRESS The atmospheric pressure when the [millibars] temperatures and height values were recorded. [MILLIBARS]
GEOPTNTL_HEIGHT The measured geopotential height. [meters] [METERS]
ATMOSPHERIC_TEMP The measured atmospheric [degrees temperature, at a given pressure. Celsius]
WIND_DIR The direction of the wind. [degrees from North]
WIND_SPEED The wind speed at the measurement [meters] height. [sec^-1]
REL_HUMID The relative humidity. [percent]
DATA_TYPE *** The type of data recorded, ranging from 0 to 5.
DATA_QUALITY ** The quality of the data, either 000000 or 404444.
FIFE_DATA_CRTFCN_CODE * The FIFE Certification Code for the data, in the following format: CPI (Certified by PI), CPI-??? (CPI - questionable data).
LAST_REVISION_DATE data, in the format (DD-MMM-YY).

Footnotes:

* Valid levels

The primary certification codes are: EXM Example or Test data (not for release) PRE Preliminary (unchecked, use at your own risk) CPI Checked by Principal Investigator (reviewed for quality) CGR Checked by a group and reconciled (data comparisons and cross checks)

The certification code modifiers are: PRE-NFP Preliminary - Not for publication, at the request of investigator. CPI-MRG PAMS data that is "merged" from two separate receiving stations to eliminate transmission errors. CPI-??? Investigator thinks data item may be questionable.

** The Data_Quality parameter must be decoded to interpret this field. Each digit represents a different parameter as listed below.

DIGIT              PARAMETER
------------   ----------------------
1               Obs_Date/Obs_Time
2               Atmospheric_Press
3               Geoptntl_Height
4               Atmospheric_Temp
5               Rel_Humid
6               Wind_Dir/Wind_Speed

The range of values for all digits and the interpretation for each is as follows:

VALUE OF DIGIT         QUALITY
----------------   -----------------
0             Correct
1             Doubtful
2             In Error
3             Replacement Value
4             Assumed or Estimated Value
9             Element Not Checked

*** The Data_Type parameter must be decoded to interpret this field. The valid values for this field are listed below along with their interpretation:

0 = Surface
1 = Mandatory
2 = Significant
3 = Generated
4 = Tropopause
5 = Maximum Wind
9 = Other Unspecified

Where:

Mandatory = Required by World Meteorological Organization as required in coded TEMP report.
Significant = Level as required to adequately describe a sounding in part B and D of the TEMP message.

Sample Data Record:

SITEGRID_ID  STATION_ID   OBS_DATE    OBS_TIME    ATMOSPHERIC_PRESS
-----------  ----------   --------    --------    -------------------
XRSD-RSN     451          01-OCT-89     1200          916
XRSD-RSN     451          01-OCT-89     1201          900
XRSD-RSN     451          01-OCT-89     1201          897
XRSD-RSN     451          01-OCT-89     1202          866
XRSD-RSN     451          01-OCT-89     1202          856
XRSD-RSN     451          01-OCT-89     1203          850
XRSD-RSN     451          01-OCT-89     1204          823
XRSD-RSN     451          01-OCT-89     1205          800
XRSD-RSN     451          01-OCT-89     1207          750
XRSD-RSN     451          01-OCT-89     1209          700
XRSD-RSN     451          01-OCT-89     1211          650
XRSD-RSN     451          01-OCT-89     1212          635
GEOPTNTL_HEIGHT  ATMOSPHERIC_TEMP   WIND_DIR   WIND_SPEED  REL_HUMID
---------------  ----------------   --------   ----------  ---------
791                 13.9            180           4         67
942                 15.5            209          11         57
970                 15.9            212          14         55
1273                 24.6            233          22         19
1375                 25.5            236          21         19
1437                 25.1            237          20         19
1719                 24.3            234          17         19
1966                 22.1            230          16         19
2521                 16.9            227          15         21
3102                 11.4            235          10         23
3715                  6.3            283           7         32
3906                  4.6            284           7         36
DATA_TYPE  DATA_QUALITY  FIFE_DATA_CRTFCN_CODE  LAST_REVISION_DATE
---------  ------------  ---------------------  ------------------
0            000000              PRE                 01-OCT-92
3            000000              PRE                 01-OCT-92
2            000000              PRE                 01-OCT-92
2            000000              PRE                 01-OCT-92
2            000000              PRE                 01-OCT-92
1            000000              PRE                 01-OCT-92
2            000000              PRE                 01-OCT-92
3            000000              PRE                 01-OCT-92
3            000000              PRE                 01-OCT-92
1            000000              PRE                 01-OCT-92
3            000000              PRE                 01-OCT-92
2            000000              PRE                 01-OCT-92

8. Data Organization:

Data Granularity:

The overall time period of data acquisition was from October 1, 1988 through October 31, 1989. Observations were made at least twice a day at 0000 GMT and 1200 GMT.

A general description of data granularity as it applies to the IMS appears in the EOSDIS Glossary.

Data Format:

The CD-ROM file format consists of numerical and character fields of varying length separated by commas. The character fields are enclosed with a single apostrophe. There are no spaces between the fields. Each file begin with five header records. Header records contain the following information: Record 1 Name of this file, its table name, number of records in this file, and principal investigator name.

Record 2 Path and filename of the previous data set, and path and filename of the next data set. (Path and filenames for files that contain another set of data taken at the same site on the same day.)

Record 3 Path and filename of the previous site, and path and filename of the next site. (Path and filenames for files of the same data set taken on the same day for the previous and next sites, sequentially numbered by SITEGRID.)

Record 4 Path and filename of the previous date, and path and filename of the next date. (Path and filenames for files of the same data set taken at the same site for the previous and next date.)

Record 5 Column names for the data within the file, delimited by commas.

Record 6 Data records begin.

Each field represents one of the attributes listed in the chart in the Data Characteristics Section and described in detail in the TDF file. These fields are in the same order as in the chart.

9. Data Manipulations:

Formulae:

Derivation Techniques and Algorithms:

Not available at this revision.

Data Processing Sequence:

Processing Steps:

The data was received from the National Climatic Data Center on 6250 BPI tapes. Data was extracted using software that was supplied in the documentation that came with these data.

Processing Changes:

These data were loaded into the appropriate table in the FIFE data base by the FIS staff. The station identification numbers that NOAA supplied with the data were the internal NOAA numbers, 13985 for Dodge City and 13996 for Topeka. The FIS staff converted these to the FIFE station identification numbers (451 and 456, respectively) and loaded them into the Station-ID column.

Missing values were given a repetitive 9 value, corresponding to the maximum digits allowed in the field.

Calculations:

None performed at this revision.

Special Corrections/Adjustments:

None performed at this revision.

Calculated Variables:

Not applicable.

Graphs and Plots:

None.

10. Errors:

Sources of Error:

The sources of error are as follows:

  1. Insufficient recorder sensitivity,
  2. Fading or weak signals,
  3. Unstable temperature traces,
  4. Leaking pressure cell,
  5. Sticking contact arm,
  6. Electrical leakage in the baseline check box, or
  7. Repeated contacts caused by faulty baroswitch assembly.

Quality Assessment:

Data Validation by Source:

When the radiosonde or ground equipment functions abnormally, the accuracy of the observed data will be noted within the data quality parameter.

Confidence Level/Accuracy Judgment:

Not available at this revision.

Measurement Error for Parameters:

Not estimated at this revision.

Additional Quality Assessments:

FIS staff performed a preliminary data quality check, examining minima and maxima of the meteorological parameters. No errors were found in the data set.

Occasionally soundings terminate abnormally, (e.g. balloon burst, leaking or floating balloon, weak or fading signal, radiosonde failure, etc.) When this occurs, if possible, another release is made close to the allotted time.

FIS staff applied a general QA procedure to the data to identify inconsistencies and problems for potential users. As a general procedure, the FIS QA consisted of examining the maximum, minimum, average, and standard deviation for each numerical field in the data table. Inconsistencies and problems found in the QA check are described is the Known Problems with the Data Section.

Data Verification by Data Center:

The data verification performed by the ORNL DAAC deals with the quality of the data format, media, and readability. The ORNL DAAC does not make an assessment of the quality of the data itself except during the course of performing other QA procedures as described below.

The FIFE data were transferred to the ORNL DAAC via CD-ROM. These CD-ROMs are distributed by the ORNL DAAC unmodified as a set or in individual volumes, as requested. In addition, the DAAC has incorporated each of the 98 FIFE tabular datasets from the CD-ROMs into its online data holdings. Incorporation of these data involved the following steps:

Each distinct type of data (i.e. "data set" on the CD-ROM), is accompanied by a documentation file (i.e., .doc file) and a data format/structure definition file (i.e., .tdf file). The data format files on the CD-ROM are Oracle SQL commands (e.g., "create table") that can be used to set up a relational database table structure. This file provides column/variable names, character/numeric type, length, and format, and labels/comments. These SQL commands were converted to SAS code and were used to create SAS data sets and subsequently to input data files directly from the CD-ROM into a SAS dataset. During this process, file names and directory paths were captured and metadata was extracted to the extent possible electronically. No files were found to be corrupted or unreadable during the conversion process.

Additional Quality Assurance procedures were performed as follows:

As errors are discovered in the online tabular data by investigators, users, or DAAC staff, corrections are made in cooperation with the principal investigators. These corrections are then distributed to users. CD-ROM data are corrected when re-mastering occurs for replenishment of CD-ROM stock.

11. Notes:

Limitations of the Data:

Not available.

Known Problems with the Data:

Missing data is reported as 999 for all fields except GEOPTNTL_HEIGHT where it is 99999.

Usage Guidance:

Not available at this revision.

Any Other Relevant Information about the Study:

Not available at this revision.

12. Application of the Data Set:

These data may be used as input to numerical models, as well as verification data for simulation studies.

13. Future Modifications and Plans:

The FIFE field campaigns were held in 1987 and 1989 and there are no plans for new data collection. Field work continues near the FIFE site at the Long-Term Ecological Research (LTER) Network Konza research site (i.e., LTER continues to monitor the site). The FIFE investigators are continuing to analyze and model the data from the field campaigns to produce new data products.

14. Software:

Software to access the data set is available on the all volumes of the FIFE CD-ROM set. For a detailed description of the available software see the Software Description Document.

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
USA

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:

NOAA Radiosonde Observations - 1989 (NCDC) are available on FIFE CD-ROM Volume 1. The CD-ROM filename is as follows:

DATA\ATMOST\NCDC_SON\GRIDgrid\YyyMmm\ydddgrid.NCR

Where xxxx is the four digit code for the location within the FIFE site grid, yy is the last two digits of the year (e.g. Y87 = 1987), mm is the month of the year (e.g. M12 = December), and ddd is the day of the year, (e.g. 061 = sixty-first day in the year). Note: capital letters indicate fixed values that appear on the CD-ROM exactly as shown here, lower case indicates characters (values) that change for each path and file.

The format used for the filenames is: ydddgrid.sfx, where grid is the four-number code for the location within the FIFE site grid, y is the last digit of the year (e.g. 7 = 1987, and 9 = 1989), and ddd is the day of the year. The filename extension (.sfx), identifies the data set content for the file (see the Data Characteristics Section) and is equal to .NCR for this data set.

17. References:

Satellite/Instrument/Data Processing Documentation.

The National Climatic Data Center documentation referred to in this report is:

TD-6200 Series NCDC Upper Air Digital Files. 1990. National Climatic Data Center. Federal Building. Asheville, NC.

Federal Meteorological Handbook No. 3. Radiosonde Observations. U.S. Department of Commerce, National Oceanic and Atmospheric Administration. Washington, D. C.

Federal Meteorological Handbook No. 4. Radiosonde Code. Second Edition-1976. U.S. Department of Commerce, National Oceanic and Atmospheric Administration. Washington, D. C.

Journal Articles and Study Reports.

FIS is unaware of any reports using this dataset. Some general publications which discuss radiosondes and/or their application within FIFE are as follows:

Brutsaert, W., M. Sugita, and L.J. Fritschen. 1990. Inner region humidity characteristics of the neutral boundary layer over prairie terrain. Water Resour. Res. 26:2931-2936.

Sugita, M. and W. Brutsaert. 1990. Wind velocity measurements in the neutral boundary layer above hilly prairie. J. Geophys. Res. 95:7617-7624.

Sugita, M. and W. Brutsaert. 1991. Daily evaporation over a region from lower boundary layer profiles measured with radiosondes. Water Resour. Res. 27:747-752.

Sellers, P.J., F.G. Hall, G. Asrar, D.E. Strebel, and R.E. Murphy. 1988. The First ISLSCP Field Experiment (FIFE). Bull. Am. Meteorol. Soc. 69:22-27.

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 Glossary.

19. List of Acronyms:

CCT Computer Compatible Tape CD-ROM Compact Disk Read-Only Memory BPI Byte per inch DAAC Distributed Active Archive Center EOSDIS Earth Observing System Data and Information System FIS FIFE Information System IFOV Instantaneous Field of View ISLSCP International Satellite Cloud Climatology Project Mbps Megabyte per second NCDC National Climatic Data Center NOAA National Oceanic and Atmospheric Administration NESDIS National Environmental Satellite Data and Information Service ORNL Oak Ridge National Laboratory URL Uniform Resource Locator UTM Universal Transverse Mercator

A general list of acronyms for the DAAC is available at Acronyms.

20. Document Information:

April 28, 1994.

This document has been reviewed by the FIFE Information Scientist to eliminate technical and editorial inaccuracies. Previous versions of this document have been reviewed by the Principal Investigator, the person who transmitted the data to FIS, a FIS staff member, or a FIFE scientist generally familiar with the data. It is believed that the document accurately describes the data as collected and archived on the FIFE CD-ROM series.

Document Review Date:

September 2, 1996 (citation revised on October 3, 2002).

Document ID:

ORNL- FIFE_NCDC_SON.

Citation:

Cite this data set as follows (citation revised on October 3, 2002):

Lutz, R. J. 1994. Atmos[pheric]. Profile: Radiosonde - NCDC (FIFE). 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/13. Also published in D. E. Strebel, D. R. Landis, K. F. Huemmrich, and B. W. Meeson (eds.), Collected Data of the First ISLSCP Field Experiment, Vol. 1: Surface Observations and Non-Image Data Sets. CD-ROM. National Aeronautics and Space Administration, Goddard Space Flight Center, Greenbelt, Maryland, U.S.A. (available from http://www.daac.ornl.gov).

Document Curator:

DAAC Staff

Document URL:

http://daac.ornl.gov