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Titel |
CO2, CO, and CH4 measurements from tall towers in the NOAA Earth System Research Laboratory's Global Greenhouse Gas Reference Network: instrumentation, uncertainty analysis, and recommendations for future high-accuracy greenhouse gas monitoring efforts |
VerfasserIn |
A. E. Andrews, J. D. Kofler, M. E. Trudeau, J. C. Williams, D. H. Neff, K. A. Masarie, D. Y. Chao, D. R. Kitzis, P. C. Novelli, C. L. Zhao, E. J. Dlugokencky, P. M. Lang, M. J. Crotwell, M. L. Fischer, M. J. Parker, J. T. Lee, D. D. Baumann, A. R. Desai, C. O. Stanier, S. F. J. De Wekker, D. E. Wolfe, J. W. Munger, P. P. Tans |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1867-1381
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Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Measurement Techniques ; 7, no. 2 ; Nr. 7, no. 2 (2014-02-25), S.647-687 |
Datensatznummer |
250115610
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Publikation (Nr.) |
copernicus.org/amt-7-647-2014.pdf |
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Zusammenfassung |
A reliable and precise in situ CO2 and CO analysis system has been
developed and deployed at eight sites in the NOAA Earth System Research
Laboratory's (ESRL) Global Greenhouse Gas Reference Network. The network
uses very tall (> 300 m) television and radio transmitter towers
that provide a convenient platform for mid-boundary-layer trace-gas
sampling. Each analyzer has three sample inlets for profile sampling, and a
complete vertical profile is obtained every 15 min. The instrument suite
at one site has been augmented with a cavity ring-down spectrometer for
measuring CO2 and CH4. The long-term stability of the systems in
the field is typically better than 0.1 ppm for CO2, 6 ppb for CO, and
0.5 ppb for CH4, as determined from repeated standard gas measurements.
The instrumentation is fully automated and includes sensors for measuring a
variety of status parameters, such as temperatures, pressures, and flow
rates, that are inputs for automated alerts and quality control algorithms.
Detailed and time-dependent uncertainty estimates have been constructed for
all of the gases, and the uncertainty framework could be readily adapted to
other species or analysis systems. The design emphasizes use of off-the-shelf parts and modularity to facilitate network operations and ease of
maintenance. The systems report high-quality data with > 93%
uptime. Recurrent problems and limitations of the current system are
discussed along with general recommendations for high-accuracy trace-gas
monitoring. The network is a key component of the North American Carbon
Program and a useful model for future research-grade operational greenhouse
gas monitoring efforts. |
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