A review of carbon monitoring in wet carbon systems using remote sensing.

Authors: CAMPBELL, A. - National Aeronautics And Space Administration (NASA); BOURGEAU-CHAVEZ, L. - Michigan Technological University; CHARLES, S. - East Carolina University; GOES, J. - Columbia University; GOMES, H. - Columbia University; HALABISKY, M. - University Of Washington; HOLMQUIST, J. - Smithsonian Environmental Research Center; LAGOMASINO, D. - East Carolina University; LOHRENZ, S. - University Of Massachusetts; MITCHELL, C. - Bigelow Laboratory For Ocean Sciences; MOSKAI, M. - University Of Washington; POULTER, B. - National Aeronautics And Space Administration (NASA); QUI, H. - University Of Wisconsin; RESENDE DE SOUSA, C. - National Aeronautics And Space Administration (NASA); SAYERS, M. - Michigan Technological University; SIMARD, M. - Jet Propulsion Laboratory; STEWART, A. - University Of Washington; SINGH, D. - Oak Ridge National Laboratory; TRETTIN, C. - Us Forest Service (FS); WU, J. - Columbia University; Zhang, Xuesong; FATOYINBO, T - National Aeronautics And Space Administration (NASA)

Submitted to: Environmental Research Letters
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/20/2022
Publication Date: 2/3/2022
Citation: Campbell, A.D., Bourgeau-Chavez, L., Charles, S.P., Goes, J., Gomes, H., Halabisky, M., Holmquist, J., Lagomasino, D., Lohrenz, S., Mitchell, C., Moskai, M., Poulter, B., Qui, H., Resende De Sousa, C.H., Sayers, M., Simard, M., Stewart, A.J., Singh, D., Trettin, C., Wu, J., Zhang, X., Fatoyinbo, T. 2022. A review of carbon monitoring in wet carbon systems using remote sensing.. Environmental Research Letters. 17:025009. https://doi.org/10.1088/1748-9326/ac4d4d.
DOI: https://doi.org/10.1088/1748-9326/ac4d4d

Interpretive Summary: Understanding the global carbon cycle is critical for designing effective policies and regulations to guide future greenhouse gas mitigation efforts. However, the carbon stocks and fluxes associated with wet environments, including rivers/streams, lakes/reservoirs, ponds, wetlands, estuaries, and coasts are not well quantified yet. In this synthesis study, we reviewed over 2000 publications to summarize the current state of the carbon budgets of different wet environments. We found that carbon stocks and fluxes of wetland environments are of large magnitude, which are often comparable to or even larger than those of other ecosystems. For example, the carbon emissions from freshwater systems, including inland wetlands, river/streams, and lakes/reservoirs, are larger than the ocean uptake carbon. Notably, the current estimates of carbon stocks and fluxes of wet environments are subject to very large uncertainties and we can only constrain them within one order of magnitude. We also recommended future directions, including the use of remote sensing data, to further bridge carbon budget gaps for wet environments.

Technical Abstract: Carbon monitoring is critical for the reporting and verification of carbon stocks and change. Remote sensing is a tool increasingly used to estimate the spatial heterogeneity, extent and change of carbon stocks across various systems. We purpose the use of the term wet carbon system to the interconnected wetlands, ocean, river and streams, lakes and ponds, and permafrost, which are carbon-dense and vital conduits for carbon throughout the terrestrial and aquatic sections of the carbon cycle. We conducted a synthesis of wet carbon monitoring studies that utilize earth observation to improve our knowledge of data gaps, methods, and future research recommendations. We conducted a systematic review collecting 1,527 references and screening them with a combination of text matching and a panel of three experts. The systematic search found 406 references, with an additional 78 references added by experts. The study found considerable variability of the utilization of remote sensing and global wet carbon monitoring progress across the nine systems analyzed. Mangroves and oceans had frequent use of remote sensing to enable global monitoring. However, seagrass, terrestrial wetlands, tidal marshes, peatlands, and permafrost would benefit from more accurate and comprehensive global maps of extent. We identified ten recommendations to continue progressing wet carbon systems and increase cross system scientific inquiry.