Methane, a far more potent greenhouse gas than carbon dioxide, is responsible for over a quarter of global warming. The 1.5°C target cannot be achieved without reducing methane emissions by 40-45% by 2030, but atmospheric concentration of methane continues to increase. The good news is that methane’s short atmospheric lifetime means taking action now can reduce atmospheric concentrations rapidly and help avert a tipping point.
Why do we need to quantify methane emissions?
The switch from coal to natural gas or oil for energy generation potentially reduces the impact on climate change by reducing CO2 emissions. However, the climate benefit may be offset by methane (CH4) leakage from natural gas and petroleum systems. Therefore, an accurate quantification of CH4 emissions from the oil and gas industry is essential.
Atmospheric measurements will play an increasingly important role in mitigation policies.
Where does the methane come from?
The major sources of methane from human activities are Agriculture (40%) Fossil fuels (35%) and Waste (20%).
Agriculture: Methane is released from the decomposition of livestock and poultry manure, from enteric fermentation from ruminant livestock (cattle, sheep, goats), and from rice cultivation.
Fossil fuels: Methane is emitted from active and abandoned coal mines, and from post-mining activities including coal processing, storage and transportation; also during oil and gas extraction activities (flaring and venting, leaks). Global oil and gas production activities have significantly increased in the last 20 years, driven in part by the increase in gas production in the United States and Russia.
Waste: Methane is produced when biodegradable wastes like food and paper decompose anaerobically, notably in landfills.
Super-emitters are facilities, equipment, and other infrastructure, typically in the fossil-fuel, waste, or agriculture sectors, that emit methane at high rates. Satellite data supplemented by spectrum analysis can zero in on methane emissions worldwide.
What's to be done?