Wetlands provide many important ecosystem services, including wildlife habitat, water purification, flood protection, and carbon metabolism. Our ability to manage these services and predict the long-term health of wetlands is strongly linked to their carbon fluxes, of which methane (CH4) is a key component. Natural wetlands emit approximately 30% of global CH4 emissions, as their waterlogged soils create ideal conditions for CH4 production. They are also the largest, and potentially most uncertain, natural source of CH4 to the atmosphere. To understand and predict CH4 fluxes across wetlands globally, we propose the first synthesis of CH4 flux tower data accompanying a global database of CH4 emissions. By taking advantage of the continuous and high-measurement frequency of flux measurements, our synthesis will provide novel insights into the controls and timing of wetland CH4 emissions for North America and globally. This database will also be used to parameterize and benchmark the performance of land-surface models of global CH4 emissions, providing a unique opportunity for informing and validating biogeochemical models. By developing the first global database of flux tower CH4 emissions and convening experts in CH4 flux measurements and modeling, we will 1) better characterize wetland carbon fluxes, 2) reduce uncertainties in the role of wetlands in the global CH4 cycle, and 3) provide metrics useful for safeguarding the many ecosystem services wetlands provide.
Additional support from the Moore Foundation.
Publications:
Chang, K.-Y., Riley, W. J., Knox, S. H., Jackson, R. B., McNicol, G., Poulter, B., Aurela, M., Baldocchi, D., Bansal, S., Bohrer, G., Campbell, D. I., Cescatti, A., Chu, H., Delwiche, K. B., Desai, A. R., Euskirchen, E., Friborg, T., Goeckede, M., Helbig, M., … Zona, D. (2021). Substantial hysteresis in emergent temperature sensitivity of global wetland CH4 emissions. In Nature Communications (Vol. 12, Issue 1). https://doi.org/10.1038/s41467-021-22452-1
Delwiche, K. B., Knox, S. H., Malhotra, A., Fluet-Chouinard, E., McNicol, G., Feron, S., Ouyang, Z., Papale, D., Trotta, C., Canfora, E., Cheah, Y.-W., Christianson, D., Alberto, M. C. R., Alekseychik, P., Aurela, M., Baldocchi, D., Bansal, S., Billesbach, D. P., Bohrer, G., … Jackson, R. B. (2021). FLUXNET-CH4: A global, multi-ecosystem dataset and analysis of methane seasonality from freshwater wetlands. In Earth Syst. Sci. Data (pp. 1–111). https://doi.org/10.5194/essd-2020-307
Knox, S. H., Bansal, S., McNicol, G., Schafer, K., Sturtevant, C., Ueyama, M., Valach, A. C., Baldocchi, D., Delwiche, K., Desai, A. R., Euskirchen, E., Liu, J., Lohila, A., Malhotra, A., Melling, L., Riley, W., Runkle, B. R. K., Turner, J., Vargas, R., … Jackson, R. B. (2021). Identifying dominant environmental predictors of freshwater wetland methane fluxes across diurnal to seasonal time scales. Global Change Biology. https://doi.org/10.1111/gcb.15661
Knox, S.H., Jackson, R.B, Poulter, B., et al. (2019) "FLUXNET-CH4 Synthesis Activity: Objectives, Observations, and Future Directions." Bulletin of the American Meteorological Society. https://doi.org/10.1175/BAMS-D-18-0268.1
Principal Investigator(s):
Rob Jackson (Stanford University)
Sara H Knox (Stanford University)
Lisamarie Windham-Myers (USGS Branch of Regional Research, Western Region)
Benjamin Poulter (National Aeronautics and Space Administration)
Participants:
Sheel Bansal (Northern Prairie Wildlife Research Center)
Jinxun Liu (USGS Western Geographic Science Center)
Benjamin Runkle (University of Arkansas)
Ankur Desai (University of Wisconsin)
William Riley (Lawrence Berkeley National Laboratory)
Rodrigo Vargas (University of Delaware)
Dennis Baldocchi (Univeristy of California, Berkeley)
Donatella Zona (San Diego State University)
Oliver Sonnentag (Université de Montréal)
Mathias Goeckede (Max Planck Institute for Biogeochemistry)
Masahito Ueyama (Osaka Prefecture University)
Torsten Sachs (GFZ German Research Centre for Geosciences)
Joe Melton (Environment and Climate Change Canada)
Annalea Lohila (Finnish Meteorological Institute)
Narasinha Shurpali (University of Eastern Finland)
Eric Ward (USGS Wetland and Aquatic Res. Center)
Zhen Zhang (University of Maryland)
Timo Vesala (University of Helsinki)
Eugenie Euskirchen (University of Alaska Fairbanks)
Karina Schafer (Rutgers University Newark)
Gavin McNicol (Stanford University)
