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EMS - Measurements of CFCs and Radiatively Important Trace Species

HF067 EML Publications Archive

Data

Overview

  • Lead: Steven Wofsy, Elaine Gottlieb
  • Investigators: Diana Barnes, Geoff Dutton, James Elkins, Michael McElroy
  • Contact: Elaine Gottlieb
  • Start date: 1996-01-01
  • End date: ongoing
  • Location: Prospect Hill Tract (Harvard Forest)
  • Latitude: +42.537755
  • Longitude: -72.171478
  • Elevation: 340 meters
  • Taxa:
  • Research topic: atmosphere
  • Study type: long-term measurement
  • LTER core area: inorganic nutrients
  • Keywords: CFCs, CH3CCl3, CO, H2, industrial pollution, N2O, PCE (C2Cl4), SF6, urban pollution
  • Release date: 1999
  • EML version: knb-lter-hfr.67.8
  • Revisions:
  • Related links:
  • Abstract:

    Measurements of 13 ozone-depleting and/or greenhouse gases are taken above the forest canopy at Harvard Forest, downwind of the New York City - Washington, D. C. corridor, every 25 minutes using a four-channel gas chromatographic system called FACTS (Forest and Atmosphere Chromatograph of Trace Species). The species measured are H2, CO, CH4, methyl chloroform (CH3CCl3), chloroform (CHCl3), carbon tetrachloride (CCl4), CFC-11 (CCl3F), CFC-12 (CCl2F2), CFC-113 (C2Cl3F3), halon-1211 (CBrClF2), perchlorethylene (C2Cl4), nitrous oxide (N2O), and sulfur hexafluoride (SF6). Observations began in January 1996 and are continuing.

  • Methods:

    FACTS is a fully automated, four-channel gas chromatograph with packed columns and electron capture detectors. Atmospheric measurements alternate with calibration standard measurements every 25 minutes; the air samples are from above the canopy of the forest (29 m).

  • Use:

    This dataset is released to the public and may be freely downloaded. Please keep the designated Contact person informed of any plans to use the dataset. Consultation or collaboration with the original investigators is strongly encouraged. Publications and data products that make use of the dataset must include proper acknowledgement. For more information on LTER Network data access and use policies, please see: http://www.lternet.edu/data/netpolicy.html.

  • Citation:

    Wofsy S, Gottlieb E. 1999. EMS - Measurements of CFCs and Radiatively Important Trace Species. Harvard Forest Data Archive: HF067.

Detailed Metadata

hf067-01: FACTS data

  1. year: year (YYYY)
  2. julian: day number from 1 January 1996 (GMT) (DDDD)
  3. DOY: day of Year (GMT) (DDD)
  4. WDIR: wind direction sector
    • 1: NE (0-90)
    • 2: SE (90-180)
    • 3: SW (180-270)
    • 4: NW (270-360)
  5. H2_ppb: Hydrogen (ppb) (dimensionless )
  6. CH4_ppb: Methane (ppb) (dimensionless )
  7. CO_ppb: Carbon Monoxide (ppb) (dimensionless )
  8. CFC12_ppt: CFC-12 (ppb) (dimensionless )
  9. H1211_ppt: Halon 1211 (ppt) (dimensionless )
  10. CFC11_ppt: CFC-11 (ppt) (dimensionless )
  11. CFC113_ppt: CFC-113 (ppt) (dimensionless )
  12. CHCl3_ppt: Chloroform (ppt) (dimensionless )
  13. MC_ppt: Methyl Chloroform (CH3CCl3) (ppt) (dimensionless )
  14. CT_ppt: Carbon Tetrachloride (CCl4) (ppt) (dimensionless )
  15. TCE_ppt: Trichloroethylene (C2HCl3) (ppt) (dimensionless )
  16. PCE_ppt: Perchloroethylene (C2Cl4) (ppt) (dimensionless )
  17. N2O_ppb: Nitrous Oxide (ppb) (dimensionless )
  18. SF6_ppt: SF6 (ppt) (dimensionless )