Botswana's Sources of CH4 Emissions
Key Insights
Methane’s Role And Sources
Methane contributes roughly 45% of Botswana's overall warming impact. Historically, livestock has been the largest source, responsible for about half of methane emissions, with crop production close behind at around two-fifths. Smaller contributions come from fugitive emissions, while waste and fuel combustion remain minor by comparison.
Livestock Rise Then Retreat
From the 1940s through the late 1960s, livestock emissions rose steadily, then climbed quickly into the late 1970s, peaking near 3 megatonnes. Through the 1980s and 2000s they were relatively stable, and since the early 2010s they have declined markedly to around 1 megatonne, easing pressure on overall methane totals.
Crop Production Now Dominant
Crop production was negligible until the early 1940s, then increased persistently for decades. Growth continued into recent years, reaching around 7 megatonnes in 2024 and at times higher, making it the largest current source and the key driver of recent methane trends.
Fugitive And Waste Trends
Fugitive emissions were minimal before the late 1970s but have risen since, nearing 1.3 megatonnes today. Waste grew gradually and accelerated after the late 2000s to about 0.5 megatonnes. Fuel combustion remains small and fairly steady around 0.2 megatonnes.
Actionable Priorities For Now
The dominant sources are moving in different directions: crop production is still rising, livestock is falling, and fugitive emissions are increasing. Consolidating the recent decline in livestock while reversing the upward trends in crop production and fugitive emissions would deliver the largest near-term gains.
Background
The chart shows a national breakdown by source of the yearly methane (CH4) emissions from human activities expressed as weight in megatonnes (Mt). In the scientific literature, these are referred to as anthropogenic emissions. Human-induced methane emissions increase atmospheric methane, which is warming the Earth. The sources of human methane emissions are
- Livestock
- Fugitive emissions from the fossil fuel industry
- Crop production
- Fossil fuel combustion
- Waste management
- Other processes
Methane's Global Warming Potential
Methane has a much higher Global Warming Potential (GWP) than CO2. However, the effect lasts only for a relatively brief period (9 years on average), compared to hundreds of years for CO2. A reduction in emissions can cause a rapid decline in its atmospheric levels and climate impact.
Livestock
Livestock emits methane that is produced in the animals' digestive system. Most methane is emitted from the mouth during rumination. A much smaller amount of methane is emitted from the manure. Depending on how the manure is managed, i.e., wet or dry, more methane is emitted. Wet management leads to higher methane emissions than dry management. However, dry management also emits nitrous oxide (N2O), which is another potent greenhouse gas.
Fugitive emissions from fossil fuel industry
Fugitive methane emissions are from the intentional and accidental release of methane, which happens during the extraction, storage, and transportation processes in the fossil fuel industry. Examples are methane leaks during oil and gas handling, storage, transport, incomplete combustion, and many more. Also, methane is deliberately ventilated from mines during the extraction of coal.
Methane is a primary part of “gas”, also called “natural gas” or “fossil gas”. Natural gas is used, for example, for heating and electricity generation, whereby it emits CO2 during the combustion process. However, when natural gas leaks (unburned) it contains a lot of fugitive methane emissions.
Waste
Waste from landfills and wastewater produces a lot of methane when biodegradable material breaks down without oxygen.
Crop production
Crop production emissions are largely from rice cultivation, which generates large amounts of methane during plant growth. These emissions are from flooded paddies, which create the swamp-like environment of rice fields. There are agricultural techniques to reduce emissions significantly, like periodic drainage and aeration. Rice is the main staple for about half the world's population, and its emissions are a significant part of total human methane emissions.
Fuel combustion
Fuel combustion emissions are mostly from the incomplete combustion of fossil fuels. As mentioned before, natural gas consists largely of methane, and when the combustion does not happen completely, methane enters the atmosphere.
Other
Other human-induced methane emissions include industrial processes and product uses.
Wikipedia: Anthropogenic Sources of Atmospheric MethaneIPCC: AR6, 5.2.2.2 Anthropogenic CH4 emissions
Units and Measures
CH4 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. Methane 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.