Iran's Sources of CH4 Emissions
Key Insights
Oil Discovery and Early Emissions
The discovery of oil in Masjed Soleyman in 1908 marked a pivotal moment for Iran's emissions profile. This event catalyzed the country's oil industry, leading to increased fossil fuel combustion and a rise in methane emissions. The establishment of the Anglo-Persian Oil Company further accelerated this trend, making Iran a significant player in the global oil market. Consequently, emissions from fuel combustion began to rise, setting the stage for future increases in greenhouse gas emissions.
Revolution and War: Emissions Fluctuations
The Iranian Revolution in 1979 and the subsequent Iran-Iraq War in 1980 caused significant disruptions in Iran's oil industry. These events led to temporary reductions in oil production and exports, resulting in a short-term decrease in methane emissions from fossil fuels. However, the post-revolutionary period saw efforts to restore and increase oil production, leading to a rebound in emissions. The war also contributed to fluctuations in emissions due to damage to oil infrastructure and increased military activity.
Modernization and Economic Reforms
In the late 20th and early 21st centuries, Iran underwent significant economic reforms under Presidents Khatami and Ahmadinejad. These reforms aimed to modernize the economy and energy sector, leading to increased fossil fuel extraction and consumption. The introduction of subsidy policies further fueled domestic consumption, resulting in a notable rise in methane emissions. Despite attempts to reduce energy subsidies in 2010, the long-term effects on emissions were mixed, highlighting the complex interplay between policy and environmental impact.
Pandemic and Recent Trends
The COVID-19 pandemic in 2020 brought about a temporary reduction in economic activity and energy consumption in Iran, leading to a decrease in methane emissions. Lockdowns and reduced transportation and industrial activity contributed to this decline. However, as the country recovers from the pandemic, emissions are likely to rebound, reflecting the ongoing challenges in balancing economic growth with environmental sustainability.
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 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.