Meteorological Control of Subtropical South American Methane Emissions Estimated from GOSAT Observations

Abstract

Numerous wetlands, including the world’s two largest contiguous wetlands, lie along the free-flowing Paraná and Paraguay Rivers that travel the length of subtropical South America (SSA) region. These wetlands are floodplains that are inundated with rising river water in flood events; their morphology and area are highly changeable with flooding extent. The long-term variability of methane emission from this wetland hotspot and its sensitivity to meteorological conditions are not well known. We herein explore this unknown using space-based estimates of methane flux for the SSA region between 2009 and 2015 along with data of water balance. We find that methane emission from this region coherently varies with precipitation and inundation areal extent.