This explains the fact that most atmospheric methane emanates from this source.

When produced in the atmosphere by the action of sunlight and oxygen on atmospheric methane and other hydrocarbons, it becomes part of smog.

Volcanoes affect atmospheric methane emissions when they erupt, releasing ash and sulfur dioxide into the air.

Following atmospheric methane excursions he postulates explosions and burning of methane would produce lots of smoke and dust, which would first lead to global cooling.

Early forms of fermentation also increased levels of atmospheric methane.