Skip to main content
SpringerLink
Log in

Eddy correlation measurement of CO2 flux using a closed-path sensor: Theory and field tests against an open-path sensor

  • Published:
Boundary-Layer Meteorology Aims and scope Submit manuscript

Abstract

We have examined the potential of using a closed-path sensor to accurately measure eddy fluxes of CO2. Five inlet tubeflow configurations were employed in the experimental setup. The fluxes of CO2 were compared against those measured with an open-path sensor. Sampling air through an intake tube causes a loss of flux, due to the attenuation of CO2 density fluctuations. Adjustments need to be made to correct for this loss and to account for density effects due to the simultaneous transfer of heat and water vapor. Theory quantifying these effects is discussed.

The “raw” CO2 flux measured with the closed-path sensor was smaller than that measured with the open-path sensor by about 15% (on average) for the turbulent tubeflow configurations with a short (≈3 m) intake tube, by 31% for turbulent tubeflow with a longer (≈6 m) intake tube and by 24% for laminar tubeflow. The difference was, in part, caused by tube attenuation of the CO2 density fluctuations and inadequate sensor time response. The elimination of the flux adjustment for the simultaneous transfer of sensible heat (i.e., the attenuation of ambient temperature fluctuations in the intake tube) generally accounted for the rest of this difference.

The raw flux measured with the closed-path sensor was corrected for frequency response and density effects. Except in the case of laminar tubeflow, the corrected closed-path flux agreed consistently with the corrected open-path flux within a few percent (<5%). These results suggest that closed-path sensors, with appropriate corrections, can be used to measure CO2 flux accurately. Recommendations are included on selecting an “optimum” flow configuration to minimize the effect of sampling air through a tube.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Baldocchi, D. D., Hicks, B. B., and Meyers, T. P.: 1988, ‘Measuring Biosphere-Atmosphere Exchanges of Biologically Related Gases with Micrometeorological Methods’,Ecology 69, 1331–1340.

    Google Scholar 

  • Barton, N. G.: 1983, ‘The Dispersion of Solute from Time-Dependent Releases in Parallel Flow’,J. Fluid Mech. 136, 243–267.

    Google Scholar 

  • Businger, J. A.: 1986, ‘Evaluating the Accuracy with which Dry Deposition Can be Measured with Current Micrometeorological Techniques’,J. Clim. Appl. Meteorol. 25, 1100–1124.

    Google Scholar 

  • Campbell, G. S. and Unsworth, M. H.: 1979, ‘An Inexpensive Sonic Anemometer for Eddy Correlation’,J. Appl. Meteorol. 18, 1072–1077.

    Google Scholar 

  • Chahuneau, F., Desjardins, R. L., Brach, E., and Verdon, R.: 1989, ‘A Micrometeorological Facility for Eddy Flux Measurements of CO2 and H2O’,J. Atmos. Oceanic Technol. 6, 193–200.

    Google Scholar 

  • Fan, S., Wofsy, S. C., Bakwin, P. S., and Jacob, D. J.: 1990, ‘Atmosphere-Biosphere Exchange of CO2 and O3 in the Central Amazon Forest’,J. Geophys. Res. 95, 16851–16864.

    Google Scholar 

  • Hartman, R. K. and Gay, L. W.: 1981, ‘Improvements in the Design and Calibration of Temperature Measurement Systems’, inProc., 15th Conf. Agric. For. Meteorol. 210 pp.

  • Hicks, B. B., Wesley, M. L., Coultier, R. L., Hart, R. L., Durham, J. L., Speer, R., and Stedman, D. H.: 1986, ‘An Experimental Study of Sulphur and NOx Fluxes Over Grassland’,Boundary-Layer Meteorol. 34, 103–121.

    Google Scholar 

  • Incropera, F. P. and DeWitt, D. P.: 1981,Fundamentals of Heat and Mass Transfer, 2nd ed., John Wiley and Sons Inc., New York.

    Google Scholar 

  • Kaimal, J. C., Wyngaard, J. C., Izumi, Y., and Cote, O. R.: 1972, ‘Spectral Characteristics of Surface-Layer Turbulence’,Quart. J. Roy. Meteorol. Soc. 98, 563–589.

    Google Scholar 

  • Lenschow, D. and Raupach, M.: 1991, ‘The Attenuation of Fluctuations in Scalar Concentrations Through Sampling Tubes’,J. Geophys. Res. 96, 15259–15268.

    Google Scholar 

  • Leuning, R. and Moncrieff, J.: 1990, ‘Eddy Covariance CO2 Flux Measurements Using Open- and Closed-Path CO2 Analysers: Corrections for Analyser Water Vapor Sensitivity and Damping of Fluctuations in Air Sampling Tubes’,Boundary-Layer Meteorol. 53, 63–76.

    Google Scholar 

  • Massman, W. J.: 1991, ‘The Attenuation of Concentration Fluctuations in Turbulent Flow in a Tube’,J. Geophys. Res. 96, 15269–15273.

    Google Scholar 

  • McMillen, R. T.: 1988, ‘An Eddy Correlation Technique with Extended Applicability to Non-Simple Terrain’,Boundary-Layer Meteorol. 43, 231–245.

    Google Scholar 

  • Moore, C. J.: 1986, ‘Frequency Response Corrections for Eddy Correlation Systems’,Boundary-Layer Meteorol. 37, 17–35.

    Google Scholar 

  • Ohtaki, E. and Matsui, M.: 1982, ‘Infra-Red Device for Simultaneous Measurement of Atmospheric Carbon Dioxide and Water Vapor’,Boundary-Layer Meteorol. 24, 109–119.

    Google Scholar 

  • Philip, J. R.: 1963a, ‘The Theory of Dispersal during Laminar Flow in Tubes, I’,Aust. J. Phys. 16, 287–299.

    Google Scholar 

  • Philip, J. R.: 1963b, ‘The Theory of Dispersal during Laminar Flow in Tubes, II’,Aust. J. Phys. 16, 300–310.

    Google Scholar 

  • Philip, J. R.: 1963c, ‘The Damping of a Fluctuating Concentration by Continous Sampling Through a Tube’,Aust. J. Phys. 16, 454–463.

    Google Scholar 

  • Taylor, G. I.: 1953, ‘Dispersion of Soluble Matter in Solvent Flowing Through a Tube’,Proc. R. Soc. London, Ser. A 219, 186–203.

    Google Scholar 

  • Taylor, G. I.: 1954, ‘The Dispersion of Matter in Turbulent Flow Through a Pipe’,Proc. R. Soc. London, Ser. A 223, 446–468.

    Google Scholar 

  • Verma, S. B.: 1990, ‘Micrometeorological Methods for Measuring Surface Fluxes’,Remote Sens. Rev. 5, 99–115.

    Google Scholar 

  • Webb, E. K., Pearman, G. I. and Leuning, R.: 1980, ‘Correction of Flux Measurements for Density Effects Due to Heat and Water Vapor Transfer’,Quart. J. Roy. Meteorol. Soc. 106, 85–100.

    Google Scholar 

  • Wesley, M. L., Eastman, D. R., Cook, D. R., and Hicks, B. B.: 1978, ‘Daytime Variations of Ozone Eddy Fluxes to Maize’,Boundary-Layer Meteorol. 15, 361–373.

    Google Scholar 

  • Zeller, K., Massman, W. J., Stocker, D., Fox, D. G., Stedman, D. and Hazlett, D.: 1989, ‘Initial Results from the Pawnee Eddy Correlation System for Dry Acid Deposition Research,USDA For. Serv. Res. Pap. RM-282, U.S. Dept. of Agric. For. Serv., Fort Collins, CO.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Agricultural Meteorology, University of Nebraska-Lincoln, 68583-0728, Lincoln, NE, USA

    Andrew E. Suyker (Graduate Student) & Shashi B. Verma (Professor)

Authors
  1. Andrew E. Suyker
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Shashi B. Verma
    View author publications

    You can also search for this author in PubMed Google Scholar

Additional information

Published as Paper No. 9938, Journal Series, Nebraska Agricultural Research Division.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Suyker, A.E., Verma, S.B. Eddy correlation measurement of CO2 flux using a closed-path sensor: Theory and field tests against an open-path sensor. Boundary-Layer Meteorol 64, 391–407 (1993). https://doi.org/10.1007/BF00711707

Download citation

  • Revised:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00711707

Keywords

Search

Navigation