Greenhouse gas emissions from nitrogen fertilizers could be reduced by up to one-fifth of current levels by 2050 with combined interventions

Abstract

Food security relies on nitrogen fertilisers, but its production and use account for approximately 5% of global greenhouse gas (GHG) emissions. Meeting climate change targets requires the identification and prioritisation of interventions across the whole lifecycle of fertilisers. Here, we have mapped the global flows of synthetic nitrogen fertilisers and manure, and their corresponding GHG emissions across their lifecycle. We have then explored the maximum mitigation potential of various interventions to reduce emissions by 2050. We found that approximately two thirds of fertiliser emissions take place after their deployment in croplands. Increasing nitrogen use efficiency is the single most effective strategy to reduce emissions. Yet, this should be combined with decarbonisation of fertiliser production. Using currently available technologies, GHG emissions of fertilisers could be reduced up to approximately one fifth of current levels by 2050.

Achieving net-zero emissions in agriculture: a review

“…Urease and nitrification inhibitors are chemicals that can be deployed along with fertilizers to prevent bacteria from performing nitrification and denitrification reactions [34]. Urease and nitrification inhibitors can minimize ammonia volatilization-an indirect source of nitrous oxide [43,126].…”

“…Synthetic fertilizers are an important input in modern agriculture, but they also contribute to about 1.01 Gt CO 2-eq per year, or 2% of global total GHG emissions (figure 1). One third of GHG emissions come from direct CO 2 emissions due to energy inputs for ammonia production [32][33][34], while two thirds are from nitrous oxide produced during soil microbial conversion of excess nitrogen-based fertilizers (figure 1(C)).…”

“…Using manure as a fertilizer may increase GHG emissions [34]. In fact, manure currently produces twice as many GHG emissions per unit of nitrogen as synthetic nitrogen fertilizers [34].…”

“…Using manure as a fertilizer may increase GHG emissions [34]. In fact, manure currently produces twice as many GHG emissions per unit of nitrogen as synthetic nitrogen fertilizers [34]. This is mainly due to the methane emissions generated during the storage and transportation of manure.…”

Estimating the renewables pull in future global green value chains

“…For ammonia, demand could be reduced by up to 48 % N and GHG emissions to 20 % of current levels by 2050 if different strategies are applied simultaneously. These strategies include water electrolysis for H 2 (the focus of our study), demand reduction, and fertiliser substitution (Gao and Cabrera Serrenho, 2023).…”