Enhanced response of global wetland methane emissions to the 2015-2016 El Niño-Southern Oscillation event

摘要: Wetlands are thought to be the major contributor interannual variability in growth rate of atmospheric methane (CH4) with anomalies driven by influence El Nino-Southern Oscillation (ENSO). Yet it remains unclear whether (i) increase total global CH4 emissions during Nino versus La Nina events is from wetlands and (ii) how large contribution wetland CH4. We used a terrestrial ecosystem model that includes permafrost dynamics estimate emissions, forced three separate meteorological reanalyses one gridded observational climate dataset, simulate spatio-temporal 1980-2016. The simulations show while responds negative annual events, instantaneous exhibits complex phase dynamics. find rates were declined at onset 2015-2016 event but then increased record-high later stages (January through May 2016). also evidence for step 7.8±1.6 Tg yr-1 2007-2014 compared average 2000-2006 using reanalyses, which equivalent ~3.5 ppb rise concentrations. mainly caused expansion area tropics (30°S-30°N) due an enhancement tropical precipitation as indicated suite reanalyses. Our study highlights role wetlands, temporal phasing ENSO, driving trends In addition, need account uncertainty forcings highlighted addressing decadal-scale fluxes.