Why do methane leaks undermine the climate benefits of switching from coal to natural gas?

• A. Methane leaks have no effect on climate benefits.
• B. Methane is less potent than CO2, so leaks do not matter.
• C. Methane is a potent greenhouse gas; leaks during extraction, transport, and distribution can offset CO2 emission savings.
• D. Methane leaks actually improve air quality.

Answer: (C)

The main idea here is life-cycle emissions: when you switch from coal to natural gas, you’re trading some CO2 from burning fuel for methane that may escape before it’s burned. Methane (the main component of natural gas) is a far more potent greenhouse gas than CO2, especially in the near term. Its global warming potential is much higher over short timescales (roughly 80–85 times CO2 over about 20 years, and about 28–36 times over 100 years). Because methane leaks can occur at many stages—during extraction, processing, transportation, and distribution—these fugitive emissions add to the atmospheric methane burden.

If the leak rate is significant, the climate advantage you gain from burning natural gas instead of coal can be reduced or even negated. In other words, the CO2 you would save by using gas could be offset by the extra warming from methane released along the supply chain. That’s why methane leaks undermine the climate benefits of switching to natural gas.

For context, this is why policy and industry efforts emphasize detecting and reducing fugitive methane emissions: to preserve the overall lower-emission profile of natural gas versus coal.

So the correct idea is that methane is a potent greenhouse gas, and leaks during extraction, transport, and distribution can offset the CO2 emission savings.