--------------------------------------------------------------------- Meteorology Measurements from the NOAA/ESRL/GMD Baseline Observatories National Oceanic and Atmospheric Administration Oceanic and Atmospheric Research Earth System Research Laboratory Global Monitoring Division -------------------------------------------------------------------- 1. DATA SOURCE AND CONTACTS These directories contain meteorology measurements at Barrow, Alaska (BRW); Mauna Loa, Hawaii (MLO); American Samoa (SMO); Summit, Greenland (SUM); Trinidad Head, California (THD) and South Pole, Antarctica (SPO), Correspondence concerning these data should be directed to: Brian Vasel NOAA ESRL Global Monitoring Division 325 Broadway, GMD-1 Boulder, Colorado, 80305 USA Telephone: 303 497-6655 Electronic Mail: brian.vasel@noaa.gov GMD.MET@noaa.gov NOAA ESRL GMD -------------------------------------------------------------------- 2. USE OF DATA These data are made freely available to the public and the scientific community in the belief that their wide dissemination will lead to greater understanding and new scientific insights. The availability of these data does not constitute publication of the data. NOAA relies on the ethics and integrity of the user to assure that ESRL receives fair credit for their work. If the data are obtained for potential use in a publication or presentation, ESRL should be informed at the outset of the nature of this work. If the ESRL data are essential to the work, or if an important result or conclusion depends on the ESRL data, co-authorship may be appropriate. This should be discussed at an early stage in the work. Manuscripts using the ESRL data should be sent to ESRL for review before they are submitted for publication so we can insure that the quality and limitations of the data are accurately represented. -------------------------------------------------------------------- 3. WARNINGS Every effort is made to produce the most accurate and precise measurements possible. However, we reserve the right to make corrections to the data based on recalibration of instruments or for other reasons deemed scientifically justified. We are not responsible for results and conclusions based on use of these data without regard to this warning. -------------------------------------------------------------------- 4. UPDATE NOTES =================================================================== 2012-08-14 Initial release of data in format described in this README. ------------------------------------------------------------------- 5. DATA - GENERAL COMMENTS 5.1 DATA - SAMPLING LOCATIONS Meteorology. The table includes the three letter code used to identify each site; the site name; latitude, longitude, and elevation (meters above sea level) of the sampling location; and country. To view near real-time data, manipulate and compare data, please visit http://www.esrl.noaa.gov/gmd/dv/iadv/. ------------------------------------------------------------------- 5.2 DATA - FILE NAME DESCRIPTION Encoded into each file name are the parameter (trace gas identifier); sampling site; sampling project; laboratory ID number; measurement group; and optional qualifiers that further define the file contents. All file names use the following naming scheme: 1 2 3 4 5 6 met_[site]_[project]_[lab ID number]_[measurement group]_[optional qualifiers].txt 1. [site] Identifies the sampling site code. (ex) brw mlo smo spo 2. [project] Identifies sampling platform and strategy. (ex) insitu 3. [lab ID number] A numeric field that identifies the measurement laboratory (1,2,3, ...). NOAA ESRL is lab number 1 (see http://www.esrl.noaa.gov/gmd/ccgg/globalview/gv_labs.html). 4. [measurement group] Identifies the group within NOAA/ESRL/GMD that makes the actual measurement. (ex) obop 5. [optional qualifiers] Optional qualifier(s) may indicate data subsetting or averaging. Multiple qualifiers are delimited by an underscore (_). (ex) hour_#### Computed hourly averages for the specified 4-digit year month_####_## Computed minute averages for the specified 4-digit year, and 2 digit month (ex) met_brw_insitu_1_obop_hour_1998.txt - Hourly averages meteorological data from Barrow, Alaska for 1998. met_brw_insitu_1_obop_minute_1998_06.txt - Minute averaged meteorological data from Barrow, Alaska for June 1998. ------------------------------------------------------------------- 5.3 DATA - HOURLY AVERAGES The hourly average data files are text files that contain meteorological observations, one line for each hour of the year, for an individual observatory. The data format is as follows: xxx yyyy mm dd hh www ss.s ff pppp.pp tt.t tt.t tt.t uu rr Fields in each line are delimited by whitespace. Fields are defined as follows: Field 1: [SITE CODE] The three-character sampling location code (see above). Field 2: [YEAR] The sample collection date and time in UTC. Field 3: [MONTH] Field 4: [DAY] Field 5: [HOUR] The hour is from 0 to 23, and signifies the beginning of the hour. For example, hour 05 is from time 05:00 to 05:59. Field 6: [WIND DIRECTION] Average wind direction from which the wind is blowing, measured clockwise in degrees from true north. North is 0 degrees, east 90 degrees, south 180, west 270 Missing values are denoted by -999 Field 7: [WIND SPEED] Units are meters/second. Missing values are denoted by -999.9 Field 8: [WIND STEADINESS FACTOR] The wind steadiness factor is 100 times the ratio of the vector wind speed to the average wind speed for the hour. Missing values are denoted by -9 Field 9: [BAROMETRIC PRESSURE] Units are hPa The station pressure is not corrected for elevation in any way. Missing values are denoted by -999.90 Field 10: [TEMPERATURE at 2 Meters] Temperature at 2 meters above ground level. Units are degrees Celsius. Missing values are denoted by -999.9 Field 11: [TEMPERATURE at 10 Meters] Temperature at 10 meters above ground level. Units are degrees Celsius. Missing values are denoted by -999.9 Field 12: [TEMPERATURE at Tower Top] Temperature at top of instrument tower. This elevation will vary depending on the site. Units are degrees Celsius. Missing values are denoted by -999.9 Field 13: [RELATIVE HUMIDITY] Units are in percent. Missing values are denoted by -99 Field 14: [PRECIPITATION INTENSITY] Amount of precipitation per hour. The precipitation amount is measured with an unheated tipping bucket rain gauge. Units are millimeters/hour. Missing values are denoted by -99 (ex) BRW 1992 12 30 20 44 5.4 -9 1005.80 -21.9 -999.9 -999.9 80 0 SPO 1993 05 06 00 95 4.5 -9 667.80 -67.8 -999.9 -999.9 -99 0 ------------------------------------------------------------------- 5.4 DATA - MINUTE AVERAGES Within each site directory, there may be additional subdirectories with names indicating a single year. Inside the yearly directories are additional files of minute averaged meteorological data, one file per month. The format of these files is the same as the hourly averaged files, except for one additional field indicating the minute of the hour (0-59). This field is inserted between the HOUR and WIND DIRECTION fields. The data format for minute average files is as follows: xxx yyyy mm dd hh nn www ss.s ff pppp.pp tt.t tt.t tt.t uu rr where nn is the minute of the hour. The minute value signifies the beginning of the minute, for example, hour 5, minute 12 is from 05:12:00 to 05:12:59 ------------------------------------------------------------------- 5.5 DATA - QUALITY SCREENING Data are screened for instrument malfunctions and non-physical values, both by visual inspection by GMD staff as well as automated algorithms. ------------------------------------------------------------------- 6. REFERENCES Mefford, T.K., M. Bieniulis, B. Halter, and J. Peterson, Meteorological Measurements, in CMDL Summary Report 1994 - 1995, No. 23, 1996, pg. 17. Herbert, G., M. Bieniulis, T. Mefford, and K. Thaut, Acquisition and Data Management Division, in CMDL Summary Report 1993, No. 22, 1994, pg. 57 Herbert, G.A., J. Harris, M. Bieniulis, and J. McCutcheon, Acquisition and Data Management, in CMDL Summary Report 1989, No. 18, 1990, Pg. 50. Herbert, G.A., E.R. Green, G.L. Koenig, and K.W. Thaut, Monitoring instrumentation for the continuous measurement and quality assurance of meteorological observations, NOAA Tech. Memo. ERL ARL-148, 44 pp, 1986. Herbert, G.A., E.R. Green, J.M. Harris, G.L. Koenig, S.J. Roughton, and K.W. Thaut, Control and Monitoring Instrumentation for the Continuous Measurement of Atmospheric CO2 and Meteorological Variables, J. of Atmos. and Oceanic Tech., 3, 414-421, 1986. -------------------------------------------------------------------