Format

Send to

Choose Destination
Sci Rep. 2017 Apr 10;7:45759. doi: 10.1038/srep45759.

Enhanced methane emissions from tropical wetlands during the 2011 La Niña.

Author information

1
Institute of Marine and Atmospheric Research Utrecht (IMAU), Utrecht, The Netherlands.
2
SRON Netherlands institute for Space Research, Utrecht, The Netherlands.
3
Department of Meteorology and Air Quality (MAQ), Wageningen University and Research Centre, WageningenThe Netherlands.
4
Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden.
5
NOAA Earth System Research Laboratory, Boulder, Colorado, USA.
6
Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA.
7
CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Beijing, China.
8
Institute on Ecosystems and Department of Ecology, Montana State University, Bozeman, USA.
9
Swiss Federal Research Institute WSL, Birmensdorf, Switzerland.
10
City College of New York, City University of New York, New York, NY, USA.
11
Institute of Arctic and Alpine Research, Boulder, CO, USA.
12
Laboratoire des Sciences du Climatet de l'Environnement (LSCE), Gif-sur-Yvette, France.

Abstract

Year-to-year variations in the atmospheric methane (CH4) growth rate show significant correlation with climatic drivers. The second half of 2010 and the first half of 2011 experienced the strongest La Niña since the early 1980s, when global surface networks started monitoring atmospheric CH4 mole fractions. We use these surface measurements, retrievals of column-averaged CH4 mole fractions from GOSAT, new wetland inundation estimates, and atmospheric δ13C-CH4 measurements to estimate the impact of this strong La Niña on the global atmospheric CH4 budget. By performing atmospheric inversions, we find evidence of an increase in tropical CH4 emissions of ∼6-9 TgCH4 yr-1 during this event. Stable isotope data suggest that biogenic sources are the cause of this emission increase. We find a simultaneous expansion of wetland area, driven by the excess precipitation over the Tropical continents during the La Niña. Two process-based wetland models predict increases in wetland area consistent with observationally-constrained values, but substantially smaller per-area CH4 emissions, highlighting the need for improvements in such models. Overall, tropical wetland emissions during the strong La Niña were at least by 5% larger than the long-term mean.

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center