Iceland's Sources of N2O Emissions
Key Insights
Agricultural Emissions Dominate
Throughout Iceland's history, agricultural activities have been the primary source of nitrous oxide (N2O) emissions. The data reveals a consistent pattern where agriculture contributes the majority of N2O emissions, peaking in the mid-20th century. This trend aligns with the expansion of livestock farming in the 1980s, which increased methane emissions due to enteric fermentation. Despite fluctuations, agriculture remains a significant contributor to Iceland's N2O emissions.
Energy Sector's Fluctuating Impact
The energy sector in Iceland has experienced notable shifts in N2O emissions over the decades. The introduction of motorized fishing vessels in the early 20th century and the expansion of the aluminum industry in the 1940s initially increased emissions. However, the transition to renewable energy sources, such as geothermal and hydroelectric power, has led to a reduction in emissions. The Reykjavik district heating expansion in 1990 and increased use of hydro power by 2000 significantly decreased reliance on fossil fuels, contributing to a decline in energy-related emissions.
Volcanic Eruptions and Natural Emissions
Iceland's unique geological activity has also played a role in its emissions profile. Volcanic eruptions, such as the Askja eruption in 1875 and the Eyjafjallajökull eruption in 2010, released substantial amounts of CO₂ and other gases into the atmosphere. While these natural events temporarily increased greenhouse gas levels, their impact is episodic and not a consistent contributor to long-term trends in anthropogenic 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 generated using a large language model (LLM) using a structured approach to improve the accuracy. This included 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.