Articles | Volume 11, issue 2
https://doi.org/10.5194/gi-11-335-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gi-11-335-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
21 Oct 2022
Research article |
| 21 Oct 2022
| 21 Oct 2022
Accuracies of field CO2–H2O data from open-path eddy-covariance flux systems: assessment based on atmospheric physics and biological environment
Xinhua Zhou
Ker Research and Development, CAS Key Laboratory of Forest Ecology and
Management, Institute of Applied Ecology, Chinese Academy of Sciences,
Shenyang 110016, China
Campbell Scientific Inc., Logan, UT 84321, USA
Ker Research and Development, CAS Key Laboratory of Forest Ecology and
Management, Institute of Applied Ecology, Chinese Academy of Sciences,
Shenyang 110016, China
Qingyuan Forest CERN, National Observation and Research Station,
Liaoning Province, Shenyang 110016, China
Ker Research and Development, CAS Key Laboratory of Forest Ecology and
Management, Institute of Applied Ecology, Chinese Academy of Sciences,
Shenyang 110016, China
Beijing Servirst Technology Limited, Beijing 100085, China
Bai Yang
Campbell Scientific Inc., Logan, UT 84321, USA
Yanlei Li
Ker Research and Development, CAS Key Laboratory of Forest Ecology and
Management, Institute of Applied Ecology, Chinese Academy of Sciences,
Shenyang 110016, China
Campbell Scientific Inc., Logan, UT 84321, USA
Fengyuan Yu
Ker Research and Development, CAS Key Laboratory of Forest Ecology and
Management, Institute of Applied Ecology, Chinese Academy of Sciences,
Shenyang 110016, China
Qingyuan Forest CERN, National Observation and Research Station,
Liaoning Province, Shenyang 110016, China
Tala Awada
School of Natural Resources, University of Nebraska, Lincoln, NE
68583, USA
Jiaojun Zhu
Ker Research and Development, CAS Key Laboratory of Forest Ecology and
Management, Institute of Applied Ecology, Chinese Academy of Sciences,
Shenyang 110016, China
Qingyuan Forest CERN, National Observation and Research Station,
Liaoning Province, Shenyang 110016, China
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To help environmental researchers better understand the sources of greenhouse gas measurements, we developed a practical method for field instruments to calculate the footprints. By using simplified math and efficient computing, our approach allows real-time analysis of measurement zones, which was previously too complex for on-site processing. This enables more accurate data collection worldwide, helping improve climate change monitoring and ecosystem studies.
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Air temperature from sonic temperature and air moisture has been used without an exact equation. We present an exact equation of such air temperature for closed-path eddy-covariance flux measurements. Air temperature from this equation is equivalent to sonic temperature in its accuracy and frequency response. It is a choice for advanced flux topics because, with it, thermodynamic variables in the flux measurements can be temporally synchronized and spatially matched at measurement scales.
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Short summary
Overall accuracy of CO2/H2O data from open-path eddy-covariance systems is modeled for data analysis. The model is further formulated into CO2 and H2O accuracy equations for uses. Based on atmospheric physics and bio-environment, both equations are used to evaluate accuracy of ecosystem CO2/H2O data and, as rationales, to assess field CO2/H2O zero and span procedures for the systems. The procedures are assessed for measurement improvement. An impractical H2O span while cold is found unnecessary.
Overall accuracy of CO2/H2O data from open-path eddy-covariance systems is modeled for data...
