Question 7 from UPSC CSE 2019 - Environment

Question

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 the atmosphere oxidizes to carbon dioxide after a decade or two.
Select the correct answer using the code given below.

Accepted Answer

Correct Option: D. 1, 2, and 3

Strategy: Accept all statements as correct. Each option aligns with established scientific facts regarding methane hydrate formation, its known locations in Arctic tundra and undersea sediments, and its role in the climate system, including its atmospheric lifetime.

Key Info: **What is Methane Hydrate?**
Methane hydrate is an ice-like solid composed of methane trapped within a water molecule lattice. It forms under high pressure and low temperatures.

**Key Characteristics and Locations**
- **Stability:** Stable in high-pressure, low-temperature environments.
- **Locations:** Commonly found in permafrost regions like the Arctic tundra and in marine sediments beneath the ocean floor along continental margins.
- **Carbon Store:** These deposits are vast and represent a significant carbon reservoir.

**Climate Connection and Impact**
- **Destabilization:** Warming oceans or thawing permafrost can destabilize hydrates, releasing methane—a potent greenhouse gas—into the atmosphere.
- **Atmospheric Lifetime:** Methane has a relatively short atmospheric lifetime of about 12 years.
- **Degradation:** It is primarily removed by oxidation with hydroxyl radicals, eventually becoming water vapor and carbon dioxide.
- **Implication:** Its rapid degradation means its climate impact can be moderated quickly if emissions are reduced.

**Dual Role**
Methane hydrates are considered both a potential energy resource and a climate change risk due to the possibility of sudden, large-scale releases.

Answer

Option A: 1 and 2 only

Answer

Option B: 2 and 3 only

Answer

Option C: 1 and 3 only