Quantifying CO 2 Uptakes Over Oceans Using LIDAR: A Tentative Experiment in Bohai Bay

• Published in: Geophysical research letters 2021-05, Vol.48 (9)
• Main Authors: Shi, Tianqi, Han, Ge, Xin Ma, Gong, Wei, Chen, Weibiao, Liu, Jiqiao, Zhang, Xingying, Pei, Zhipeng, Gou, Hailong, Bu, Lingbing
• Format: Article
• Language: English
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2020GL091160

Oceans are widely regarded as major offsets for anthropogenic carbon emissions, leading to an evident lower measured atmospheric CO 2 concentration than expected. It is thus of great significance to develop effective means to monitor CO 2 fluxes over oceans globally. In this work, we utilized observations obtained by an airborne CO 2 ‐IPDA LIDAR to evaluate the potential of such means in estimating sea‐air CO 2 flux. During a flight experiment in 2019, we have estimated the CO 2 exchange rate, −1.5 ± 0.18 mmol/m 2 /h, between the Bohai Bay and the atmosphere using equilibrium atmospheric boundary layer theory. These findings indicated that the forthcoming space‐borne CO 2 ‐IPDA LIDAR is capable of identifying CO 2 uptakes over oceans qualitatively, which would be a novel means and a basis for monitoring CO 2 fluxes over global oceans. Oceans are regarded as important offsets to anthropogenic CO 2 emissions, delaying an increase in atmospheric CO 2 concentration. However, there is a lack of understanding of the intensity, distribution, and variability of marine carbon sinks. China is due to launch a space‐borne LIDAR for measuring atmospheric CO 2 concentration globally in 2021. In this work, we utilized data collected during a flight test for the forthcoming satellite mission to explore the ability of such a novel means in revealing and estimating CO 2 fluxes of oceans quantitatively. Results confirmed an evident CO 2 uptake in the Bohai Bay and exhibited a promising prospect for the novel CO 2 measuring means. We detected XCO 2 gradient during a flight campaign in China Retrieve XCO 2 in the atmosphere boundary layer by cloud slicing method Provide a model to retrieve CO 2 flux over ocean by CO 2 ‐IPDA system