  1) The annual cycle of atmospheric methane in southern high latitudes is
extremely highly correlated with Antarctic sea ice extent. 2) The annual cycle
of atmospheric methane in the Arctic is highly correlated with Antarctic or
Arctic plus Antarctic sea ice extent. 3) We propose the global annual cycle of
atmospheric methane is largely driven by Antarctic sea ice dynamics, with
relatively stronger influence from other fluxes (probably the biota) in the
Northern Hemisphere. 4) We propose degassing during sea ice freeze and
temperature dependent solubility in the ocean dominate the annual methane
cycle. 5) Results provide evidence that carbon cycle pathways, parameters and
predictions must be reassessed.
