South Africa's Sources of N2O Emissions
Key Insights
Long-Term Pattern And Scale
South Africa's nitrous oxide emissions are shaped above all by agriculture, which accounts for around 70% of the total. A pronounced jump during the post‑war era lifted agricultural emissions from single digits into the low teens of megatonnes, setting the level that has largely defined the national picture since.
Agriculture’s Surge Then Plateau
After that rapid rise in the 1940s, agriculture eased in the 1950s and then crept upward through the latter 20th century. Since the late 1990s, it has stayed broadly stable, fluctuating in a narrow band in the low‑teens megatonnes, with small ups and downs but no sustained growth.
Energy, Industry, And Other
Energy-related emissions climbed steadily from the mid‑20th century, peaking in the mid‑2010s at around 3 megatonnes before edging down in recent years. Industry followed a different path: growth to a late‑1990s peak near 4 megatonnes, then a marked decline to well under 1 megatonne today. The "other" category has risen gradually since the 1970s into the low single‑digits, while waste remains a small and fairly steady contributor.
What The Trend Suggests
The current trajectory is dominated by a high but stable agriculture sector, a modest recent decline in energy, a sustained fall in industry, and a slow rise in other. Keeping agriculture from drifting upward, accelerating declines in energy, and sustaining industry's downward path-while checking the rise in other-will determine the overall direction of South Africa's N2O 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.