Satellite methane observations constrain latitudinal distribution of wetland emissions and their climate sensitivity
Shuang Ma, Jet Propulsion Laboratory at Caltech, shuang.ma@jpl.nasa.gov (Presenter)
John R Worden, Jet Propulsion Laboratory at Caltech, john.r.worden@jpl.nasa.gov
Alexis Anthony Bloom, Jet Propulsion Laboratory at Caltech, abloom@jpl.nasa.gov
Yuzhong Zhang, School of Engineering, Westlake University, Hangzhou, Zhejiang Province, China, yuzhongzhang@seas.harvard.edu
Benjamin Poulter, NASA GSFC, benjamin.poulter@nasa.gov
Daniel H Cusworth, Jet Propulsion Laboratory at Caltech, daniel.cusworth@jpl.nasa.gov
Yi Yin, Division of Geological and Planetary Sciences, California Institute of Technology, yiyin@caltech.edu
Sudhanshu Pandey, SRON Netherlands Institute for Space Research, s.pandey@sron.nl
Joannes D Maasakkers, SRON Netherlands Institute for Space Research, j.d.maasakkers@sron.nl
Xiao Lu, School of Engineering and Applied Sciences, Harvard University, xiaolu@g.harvard.edu
Lu Shen, School of Engineering and Applied Sciences, Harvard University, lshen729@gmail.com
Jianxiong Sheng, Center for Global Change Science, Massachusetts Institute of Technology, shengj@mit.edu
Christian Frankenberg, Division of Geological and Planetary Sciences, California Institute of Technology, cfranken@caltech.edu
Charles Miller, NASA JPL, charles.e.miller@jpl.nasa.gov
Daniel Jacob, Harvard University, djacob@fas.harvard.edu
Wetland methane (CH4) emissions represent about 30% of the global CH4 budget and remain its most uncertain component. However, large differences in wetland CH4 latitudinal distribution and climate sensitivity exist between bottom-up estimates, informed by ground flux measurements, and top-down estimates inversed from atmospheric CH4 concentration. Despite the extensive coverage of satellite CH4 concentration observations, challenges remain with using top-down estimates to test and refine bottom-up models, mainly because of variable a priori emissions and corresponding variable spatial resolution. We present an approach to test and update bottom-up wetland models that comprehensively account for uncertainties in satellite-based CH4 flux estimates. We present a satellite-constrained wetland CH4 ensemble product derived from assembling the highest-performance bottom-up models. Our results place new constraints on the latitudinal distribution of wetland emissions and their climate sensitivity. We find ~25% less global emissions from best-fit bottom-up models while the relative contribution of tropical emissions to the total is ~10% higher. Our results also indicate that hydrological controls on tropical wetland emissions are the dominant regulator of global wetland emission contributions to the atmospheric CH4 budget.
Poster: Poster_Ma__11_25.pdf
Presentation Type: Poster
Session: 3.5a Flux estimates and atmospheric inversions from space-based GHG measurements
Session Date: Wednesday (6/16) 12:00 PM