Ireland's Sources of N2O Emissions
Key Insights
Agriculture Dominates The Picture
Ireland's nitrous oxide profile is shaped primarily by agriculture, which makes up almost 90% of national N2O and, on its own, contributes over a quarter of the country's overall greenhouse warming impact. Energy, industry, waste, and other sources together remain much smaller in comparison.
Rise Then Long Plateau
Agricultural emissions were low and steady through the early 20th century, stepped up during the post‑war era, and climbed through the late 1940s to the mid‑1990s, reaching around 9 megatonnes. Since then, they have edged down slightly and held fairly steady, generally fluctuating between about 8 and 9 megatonnes with limited volatility.
Smaller Sources Shift Modestly
Industry rose from negligible levels mid‑century to just over 1 megatonne in the early 1970s, then declined steadily and now sits at a small fraction of that. Energy stayed low for most of the record, increased toward the mid‑2010s, and has been falling quickly since. "Other" and waste have been comparatively stable at low levels across the long run.
Current Priorities And Pace
The largest source-agriculture-is on a gentle downward path but essentially stable at a high level, so faster reductions are needed to change the national total. Industry, while now a modest share, continues to decline; keeping that trend going helps at the margin, but meaningful progress hinges on accelerating the slowdown in agricultural emissions.
Background
The chart shows a national breakdown by source of the yearly nitrous oxide (N2O) emissions from human activities and processes, expressed as weight in megatonnes (Mt). Human-induced emissions are the main driver of the increasing atmospheric nitrous oxide that is warming our planet. The sources of human nitrous oxide emissions are
- Agriculture
- Energy
- Industry
- Waste
- Other
Agriculture
Emissions related to agriculture are mainly from the use of synthetic fertilizers and manure management.
Synthetic fertilizer, used for agricultural processes, contains a lot of nitrogen. That nitrogen in the soil reacts and causes considerable N2O emissions. The use of excess fertilizer, meaning more fertilizer than the plants can use to grow, causes even higher relative emissions. Applying the right amount of fertilizer at the right time can reduce N2O emissions. There are many technical solutions to reduce emissions while keeping, or even increasing, agricultural yields.
When manure is left on the field or otherwise managed in dry processes, it emits considerable amounts of nitrous oxide. Manure can be managed by wet processes, which reduces nitrous oxide emissions but increases methane emissions. Some technical solutions focus on modifying the animal feed to reduce the nitrogen in the manure, thereby reducing nitrous oxide emissions.
Energy, Industry, Waste, and Other
All non-agricultural categories together have much lower emissions than agricultural emissions alone.
N2O emissions related to energy are almost all from the combustion of fossil fuels. For example, the combustion of fossil fuels in power plants, cars, and airplanes not only causes CO2 emissions but also emits nitrous oxide (N2O). Any advances to reducing fossil fuel dependency will thus also reduce nitrous oxide emissions.
Most industry-related emissions are from the chemical industry for producing fertilizer, nylon, and similar products. Technologies are available to reduce emissions in these processes.
Nitrous oxide emissions from waste come from, for example, wastewater treatment and landfills.
Wikipedia: Nitrous oxideIPCC: AR6, 5.16 Anthropogenic nitrous oxide (N2O) emissions
Units and Measures
N2O emissions are expressed in the total weight in megatonnes per year. 1 Megatonne is equal to 1 million tonnes.
Wikipedia: MegatonneWikipedia: Global warming potential
About the Data
The last available year in all the emission datasets is 2023. N2O emissions come from the PRIMAP-Hist dataset. It is a rich dataset that combines several published sources to create a historical emissions time series for various greenhouse gases.
The Key Insights paragraph was created using a large language model (LLM) in combination with our data, historic events, and a structured approach for best accuracy by separating the context generation from the interpretation and narrative.
Data Sources
PRIMAP-hist The PRIMAP-hist national historical emissions time series (1750-2023)
Update cycle: Every few monthsDelay: Less than 1 yearCredits: Gütschow, Johannes; Busch, Daniel; Pflüger, Mika (2024): The PRIMAP-hist national historical emissions time series (1750-2023) v2.6. Zenodo.