Which of the following statements are correct about the deposits of 'methane hydrate'? 1. Global warming might trigger the release of methane gas from these deposits. 2. Large deposits of 'methane hydrate' are found in Arctic Tundra and under the seafloor. 3. Methane in atmosphere oxidizes to carbon dioxide after a decade or two. Select the correct answer using the code given below.
- (a) 1 and 2 only
- (b) 2 and 3 only
- (c) 1 and 3 only
- (d) 1, 2 and 3 ✓ UPSC's answer
Why the answer is (d)
• Methane hydrate (clathrate) is methane locked in an ice lattice under high pressure and low temperature, found beneath permafrost in the Arctic tundra and in seafloor sediments on continental margins (statement 2); India has deposits in the Krishna–Godavari basin.
• Warming of permafrost and ocean waters could destabilise hydrates and release methane, a positive feedback sometimes called the 'clathrate gun' (statement 1).
• Methane has an atmospheric lifetime of roughly 12 years before oxidising to CO2 and water (statement 3).
• Hence 1, 2 and 3, option (d).
Why the other options are wrong
- (a) 1 and 2 only
- Statement 3 on methane oxidation is also correct.
- (b) 2 and 3 only
- Statement 1 on warming-triggered release is also correct.
- (c) 1 and 3 only
- Statement 2 on deposit locations is also correct.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2019, held on 2 June 2019. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.