Carbon emissions from fertilizers could be reduced by as much as 80% by 2050
The researchers, from the University of Cambridge, found that two thirds of emissions from fertilisers take place after they are spread on fields, with one third of emissions coming from production processes. Although nitrogen-based fertilisers are already known to be a major source of greenhouse gas emissions, this is the first time that their overall contribution, from production to deployment, has been fully quantified. Their analysis found that manure and synthetic fertilisers emit the equivalent of 2.6 gigatonnes of carbon per year -- more than global aviation and shipping combined. Carbon emissions from fertilisers urgently need to be reduced; however, this must be balanced against the need for global food security. Earlier research has estimated that 48% of the global population are fed with crops grown with synthetic fertilisers, and the world's population is expected to grow by 20% until 2050. The Cambridge researchers say that a combination of scalable technological and policy solutions are needed to reduce fertiliser emissions while maintaining food security. However, they estimate that if such solutions could be implemented at scale, the emissions from manure and synthetic fertilisers could be reduced by as much as 80%, to one-fifth of current levels, without a loss of productivity. Their results are repod in the journal Nature Food.