A review of datasets and methods for deriving spatiotemporal distributions of atmospheric CO2. (15th November 2022)

• Record Type: Journal Article
• Authors: He, Changpei; Ji, Mingrui; Grieneisen, Michael L.; Zhan, Yu
• Is Part Of: Journal of environmental management. Volume 322(2022)
• Publication Date: 2022-11-15
• Subjects: Carbon dioxide -- Ground-based network -- Satellite retrieval -- Chemical transport model -- Geostatistical interpolation -- Machine learning; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2022.116101
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: As the most abundant greenhouse gas, atmospheric carbon dioxide (CO2 ) is considered one of the main attributors to climate change. Atmospheric CO2 concentrations can be measured by ground-based monitoring networks, mobile monitoring campaigns, and carbon-observing satellites. However, the worldwide ground-based monitoring networks are composed of sparsely distributed sites and are inadequate to represent the spatiotemporal distributions of CO2 . Satellite-based remote sensing features repeated, long-term, and large-scale measurements, so it plays a crucial role in monitoring the global distributions of atmospheric CO2 . However, due to the presence of heavy clouds (or aerosols) and the limitation of satellite orbiting tracks, there exist large amounts of missing data in satellite retrievals. Various methods, including chemical transport models (CTMs), geostatistical methods, and regression-based models, have been employed to derive full-coverage spatiotemporal distributions of CO2 based on the limited CO2 measurements. This review summarizes the strengths and limitations of these methods. However, CTMs simulation results can have high uncertainty due to imperfect knowledge of the real world, and the interpolation accuracy of all geostatistical methods is limited by the large amount of data gaps in current satellite retrieved CO2 products. To overcome these limitations, regression-based methods (especially machine learning models) have the ability to predict CO2 with superior predictive performance, so this review also summarizes the framework of the machine learning approach. Leveraging the ongoing advancements of satellite instrumentation, the satellite-based CO2 products have been improving dramatically in recent decades, and this review will describe and critically assess the advantages and disadvantages of the currently used systems in detail. For future improvements, we recommend the fusion of data from multiple satellite retrievals and CTMs by using machine learning algorithms in order to obtain even longer-term, larger-scale, finer-resolution, and higher-accuracy CO2 datasets. Graphical abstract: Datasets and methods to derive full-coverage spatiotemporal distributions of CO2 . Image 1 Highlights: Remote sensing is crucial to monitoring the global distributions of atmospheric CO2 . This review assesses the pros and cons of the remote-sensing CO2 datasets. This review summarizes the strengths and limitations of various methods for mapping CO2 . This review summarizes machine learning framework for simulating CO2 distribution. Fusing multiple satellite products is recommended for deriving CO2 distributions.