Articles | Volume 15, issue 1
https://doi.org/10.5194/amt-15-95-2022
© 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/amt-15-95-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Air temperature equation derived from sonic temperature and water vapor mixing ratio for turbulent airflow sampled through closed-path eddy-covariance flux systems
Xinhua Zhou
Campbell Scientific Inc., Logan, Utah 84321, USA
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
Eugene S. Takle
Department of Agronomy, Iowa State University, Ames, Iowa 50011, USA
Xiaojie Zhen
Beijing Techno Solutions Ltd., Beijing 100088, China
Andrew E. Suyker
School of Natural Resources, University of Nebraska–Lincoln, Lincoln, Nebraska 68583, USA
Tala Awada
School of Natural Resources, University of Nebraska–Lincoln, Lincoln, Nebraska 68583, USA
Jane Okalebo
School of Natural Resources, University of Nebraska–Lincoln, Lincoln, Nebraska 68583, USA
Jiaojun Zhu
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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Short summary
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.
Air temperature from sonic temperature and air moisture has been used without an exact equation....