Growing methane emissions linked to food production risk jeopardising global warming targets, according to new research.
The report published in the journal Environmental Research Letters found that emissions of the potent greenhouse gas are growing at the fastest rate in decades, as opposed to carbon dioxide emissions which research shows have levelled out in recent years.
It found methane emissions from increasing agricultural activities seemed to be a major, possibly dominant, cause of current atmospheric growth trends. Livestock, in particular ruminants such as cows and sheep, are major producers of methane, which is also emitted in the production of staple foods such as rice.
The authors concluded that keeping global warming below the 2°C agreed in Paris last year was already a challenging target with most of the attention to date placed on reducing carbon emissions. They added that such a target would become increasingly difficult to achieve if reductions in methane emissions are not also addressed strongly and rapidly.
Potential mitigation opportunities include modifying the diet of ruminant animals or changing agricultural practices; however the authors said these would need to be balanced against the need to maintain the quality of meat and milk and guarantee food supplies.