Atmospheric Carbon Dioxide Record from In Situ Measurements at Baring Head (1970 - 1993)
Abstract
Determinations of atmospheric CO2 mixing ratios are made using a Siemens Ultramat-3 nondispersive infrared (NDIR) gas analyzer. The NDIR CO2 analyzer is connected via a gas manifold consisting of stainless steel tubing and computer-controlled solenoid switches to 12 gas cylinders and 2 sample air lines. The NDIR analyzer compares ambient air CO2 mixing ratios relative to known CO2 mixing ratios in tanks of compressed reference gases. The analyzer operates in a differential mode, with a "zero" reference gas of CO2 mixing ratio 20 to 30 parts per million (ppm) below ambient air CO2 levels flowing continuously through one cell of the analyzer at ~10 mL/min. When atmospheric CO2 is measured, a diaphragm pump pulls air through a sampling line at ~5 L/min. A small fraction of this (180 mL/min) is dried cryogenically to a temperature of approximately ¬70° Celsius and passed through the sample cell of the CO2 analyzer. Both the "zero" and sample gas are exhausted into the observatory building.
- Authors:
-
- National Institute of Water and Atmospheric Research, Ltd., Lower Hutt, New Zealand
- National Institute of Water and Atmospheric Research, Ltd. Lower Hutt, New Zealand
- Publication Date:
- Research Org.:
- Environmental System Science Data Infrastructure for a Virtual Ecosystem (ESS-DIVE) (United States); Carbon Dioxide Information Analysis Center (CDIAC), Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Biological and Environmental Research (BER)
- Subject:
- 54 ENVIRONMENTAL SCIENCES
- OSTI Identifier:
- 1394197
- DOI:
- https://doi.org/10.3334/CDIAC/ATG.017
Citation Formats
Manning, M. R., Gomez, A. J., and Pohl, K. P. Atmospheric Carbon Dioxide Record from In Situ Measurements at Baring Head (1970 - 1993). United States: N. p., 1994.
Web. doi:10.3334/CDIAC/ATG.017.
Manning, M. R., Gomez, A. J., & Pohl, K. P. Atmospheric Carbon Dioxide Record from In Situ Measurements at Baring Head (1970 - 1993). United States. doi:https://doi.org/10.3334/CDIAC/ATG.017
Manning, M. R., Gomez, A. J., and Pohl, K. P. 1994.
"Atmospheric Carbon Dioxide Record from In Situ Measurements at Baring Head (1970 - 1993)". United States. doi:https://doi.org/10.3334/CDIAC/ATG.017. https://www.osti.gov/servlets/purl/1394197. Pub date:Sat Jan 01 00:00:00 EST 1994
@article{osti_1394197,
title = {Atmospheric Carbon Dioxide Record from In Situ Measurements at Baring Head (1970 - 1993)},
author = {Manning, M. R. and Gomez, A. J. and Pohl, K. P.},
abstractNote = {Determinations of atmospheric CO2 mixing ratios are made using a Siemens Ultramat-3 nondispersive infrared (NDIR) gas analyzer. The NDIR CO2 analyzer is connected via a gas manifold consisting of stainless steel tubing and computer-controlled solenoid switches to 12 gas cylinders and 2 sample air lines. The NDIR analyzer compares ambient air CO2 mixing ratios relative to known CO2 mixing ratios in tanks of compressed reference gases. The analyzer operates in a differential mode, with a "zero" reference gas of CO2 mixing ratio 20 to 30 parts per million (ppm) below ambient air CO2 levels flowing continuously through one cell of the analyzer at ~10 mL/min. When atmospheric CO2 is measured, a diaphragm pump pulls air through a sampling line at ~5 L/min. A small fraction of this (180 mL/min) is dried cryogenically to a temperature of approximately ¬70° Celsius and passed through the sample cell of the CO2 analyzer. Both the "zero" and sample gas are exhausted into the observatory building.},
doi = {10.3334/CDIAC/ATG.017},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1994},
month = {1}
}
Works referencing / citing this record:
Bomb 14C enrichment indicates decadal C pool in deep soil?
journal, June 2007
- Baisden, W. Troy; Parfitt, Roger L.
- Biogeochemistry, Vol. 85, Issue 1