Malawi's Sources of N2O Emissions
Key Insights
Agricultural Expansion Drives Emissions
Malawi's N₂O emissions have been significantly influenced by agricultural activities, particularly since the late 19th century. The establishment of the British Protectorate in 1891 marked the beginning of intensified agricultural practices, which set the stage for future emissions growth. The introduction of hybrid maize in the 1970s further accelerated this trend, as increased fertilizer use contributed to rising N₂O emissions. By the 21st century, agriculture had become the dominant source of N₂O emissions, with a notable surge in the 2010s.
Policy Changes and Emission Trends
The transition to multiparty democracy in 1994 and the launch of a fertilizer subsidy program in 2005 were pivotal in shaping Malawi's emission profile. These policy shifts encouraged agricultural expansion and intensified fertilizer use, leading to increased N₂O emissions. The 2005 subsidy program, in particular, aimed to boost food security but also resulted in a marked rise in emissions from agricultural soils.
Natural Disasters and Emission Fluctuations
Natural events have also played a role in Malawi's emission history. Severe flooding in 2015 and the impact of Cyclone Idai in 2020 led to land-use changes and deforestation, contributing to fluctuations in emissions. These events underscore the vulnerability of Malawi's agricultural sector to environmental disruptions, which can have lasting impacts on emission levels.
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.