EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

A portable dual-channel laser heterodyne radiometer for simultaneous remote measurements of CH4 and CO2 in the atmospheric column

Jingjing Wang2, Tu Tan2, Zhengyue Xue2, Xiaoming Gao2, and Weidong Chen1
Jingjing Wang et al.
  • 1Laboratoire de Physicochimie de l’Atmosphère, Université du Littoral Côte d’Opale, 59140 Dunkerque, France
  • 2Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, 230031 Hefei, China

Laser heterodyne spectroscopic measurement technique[1] has been proved to be a powerful and effective remote sensing tool for measurements of greenhouse gases in the atmospheric column[2-6]. In the present work, we report the development of a portable all-fiber coupled dual-channel laser heterodyne radiometer (LHR) and its field deployment. Two DFB lasers operating at 1650.9 nm and 1603.6 nm are used for the remote measurements of column CH4 and CO2, respectively. A fiber optic switch is used to modulate and split the collected sunlight into two channels for simultaneous measurements of both target greenhouse gases. Custom-made preamplifiers combined with digital lock-in amplifiers are used to extract the laser heterodyne signals. The spectral resolution of the instrument is about 0.00442 cm-1, and the signal-to-noise ratio of the measured spectrum of about 250 is achieved with 0.8 s average time per sampling datum. The developed LHR instrument was successfully deployed to a field atmospheric observation experiment (in Dachaidan district, Qinghai province, China).

The experimental detail including the LHR instrument integration, dual-channel measurement results of column CH4 and CO2 and preliminary data inversion results will be presented and discussed.

Acknowledgments. The project was supported by the national key R&D program of China (2017YFC0209705). The authors thank the financial supports from the CPER CLIMIBIO program, the Labex CaPPA project (ANR-10-LABX005).


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[2] E. L. Wilson, A. J. DiGregorio, G. Villanueva, C. E. Grunberg, et al., Appl. Phys. B 125 (2019) 211-219.

[3] D. S. Bomse, J. E. Tso, M. M. Flors, J. H. Miller, Appl. Opt. 59 (2020) B10-B17.

[4] J. Wang, G. Wang, T. Tan, G. Zhu, C. Sun, Z. Cao, W. Chen, X. Gao, Opt. Express 27 (2019) 9610-9619

[5] A. Rodin, A. Klimchuk, A. Nadezhdinskiy, D. Churbanov, et al., Opt. Express 22 (2014) 13825-13834.

[6] E. L. Wilson, M. L. McLinden, J. H. Miller, H. R. Melroy, et al., Appl. Phys. B 114 (2014) 385-393.

How to cite: Wang, J., Tan, T., Xue, Z., Gao, X., and Chen, W.: A portable dual-channel laser heterodyne radiometer for simultaneous remote measurements of CH4 and CO2 in the atmospheric column, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-16428,, 2021.

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