Which of the following statements are correct about the deposits of ‘methane hydrate’? I. Global warming might trigger the release of methane gas from these deposits. II. Large deposits of ‘methane hydrate’ are found in Arctic Tundra and under the seafloor. III. Methane in atmosphere oxidizes to carbon dioxide after a decade or two. Select the correct answer using the code given below:

Methane hydrate is methane trapped in a cage of water molecules, stable only at low temperature and high pressure. That is why it occurs beneath Arctic permafrost (Siberia, Alaska, Canada) and in continental margin sediments under the seafloor, so statement II is correct.

Statement I is also correct. As temperatures rise, hydrates destabilise and release methane. Methane is a far more potent greenhouse gas than CO2 over a 20-year horizon, which creates a positive feedback loop linked to Arctic amplification.

Statement III is correct too. Atmospheric methane has a lifetime of roughly a decade, and it is removed mainly by reaction with hydroxyl radicals, which converts it to CO2 and water vapour.

• A (1 and 2 only): wrongly rejects III.
• B (2 and 3 only): wrongly rejects I, the warming link the question tests.
• C (1 and 3 only): wrongly rejects II.

Mains link: hydrates are both a climate risk and a future energy source; India has explored them in the Krishna-Godavari basin.

Trap: Students doubt statement III, assuming methane persists for centuries like CO2.