Portugal's Sources of N2O Emissions
Key Insights
Agricultural Dominance and Fluctuations
Throughout the decades, Portugal's N₂O emissions have been predominantly driven by agriculture. The mid-20th century saw a significant rise in emissions from this sector, peaking around the 1980s. This trend aligns with post-war industrialization, which likely intensified agricultural activities. However, recent decades have shown a decline, possibly due to modern agricultural practices and EU regulations.
Industrial Peaks and Declines
The industrial sector experienced a notable surge in N₂O emissions during the 1960s and 1970s, coinciding with Portugal's post-war industrial boom. This was followed by a sharp decline in the 1980s, reflecting economic and political shifts, such as the Carnation Revolution. The introduction of natural gas in 1991 further contributed to reducing industrial emissions, as cleaner energy sources replaced more polluting ones.
Energy and Waste Contributions
Energy-related N₂O emissions have shown a gradual increase, particularly during the late 20th century, as Portugal's energy consumption grew. However, the expansion of renewable energy in the 2000s has helped stabilize these emissions. Waste management has also played a role, with emissions from this sector steadily rising, reflecting increased urbanization and waste production.
Recent Trends and Future Outlook
In recent years, Portugal's overall N₂O emissions have been on a downward trend, thanks to renewable energy investments and improved agricultural practices. The COVID-19 pandemic in 2020 temporarily reduced emissions, highlighting the potential for sustainable recovery strategies. As Portugal continues to focus on reducing its carbon footprint, these efforts are likely to shape future emission trends.
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.