This colorless gas is more abundant than carbon dioxide (CO₂) yet it is almost 300 times more potent than CO₂ over a 100-year period. To be specific, it has a Global Warming Potential (GWP) of 278 as per IPCC’s latest report.
N₂O levels are on a concerning upward trajectory. The Global Carbon Project reports that our atmosphere held a concentration of around 270 parts per billion (ppb) of N₂O in the 1700s. Fast forward to 2022, that number has skyrocketed to over 336 ppb – a record high not seen in at least 800,000 years. The cause? Largely human activity.
Agriculture: main source of N₂O emissions
Fertilizers are a major factor, as they release N₂O during microbial processes like nitrification and denitrification in the soil. When nitrogen from fertilizers isn’t fully absorbed by crops, it can escape as nitrous oxide, making agricultural soils a key contributor to emissions.
Industrial processes and fossil fuel use also contribute a lot towards N₂O, though to a lesser extent than agriculture.
There are natural N₂O emissions coming from soils and oceans which have remained stable, indicating that the recent spikes are human-driven.
A worrying trend in N₂O emissions
Between 2020 and 2022, N₂O emissions increased at the fastest rate on record—over 30% higher than the previous decade's average. This accelerating rate underscores the urgent need to address emissions, especially from agriculture, which dominates global N₂O outputs.
Regional differences
The global picture of N₂O emissions is far from uniform. Europe has achieved reductions through industrial and agricultural improvements, but regions like China and South Asia are experiencing alarming increases—over 80% in some cases. This rise is closely linked to agricultural intensification and expanded fertilizer use in these areas.
There is comprehensive study by Earth System Science Data on N₂O trends and solutions which we strongly encourage you to read more about here.
The path forward
The upward trend in N₂O levels reflects how human activity has disrupted the natural balance. To curb N₂O’s impact, the focus must be on better agricultural practices and responsible fertilizer production, type, and use. This requires collective efforts across sectors, involving governments, scientists, and the agriculture industry, to reduce N₂O emissions through innovative practices.
How can you curb unnecessary N₂O emissions?
Inhibitors, such as urease and nitrification inhibitors, reduce nitrogen losses by slowing its conversion into nitrate, which supports plant growth, rather than forming into nitrous oxide or ammonia gas. Another solution comes in the form of controlled-release fertilizers (CRFs). They provide nutrients steadily, aligning with plant needs and minimizing excess.
These approaches improve nutrient efficiency and help lower greenhouse gas emissions, making them effective tools for more sustainable fertilizer use.
Are you working with inhibitors or CRF?
You could benefit from working with Proba. We help organizations scale sustainable practices through insetting and carbon finance, supporting the hard-to-abate supply chains to adopt greener technologies. Reach out to explore how we can help.