‘मेथैन हाइड्रेट’ के निक्षेपों के बारे में, निम्नलिखित में से कौन-से कथन सही हैं?
- 1.भूमंडलीय तापन के कारण इन निक्षेपों से मेथैन गैस का निर्मुक्त होना प्रेरित हो सकता है।
- 2.‘मेथैन हाइड्रेट’ के विशाल निक्षेप उत्तरध्रुवीय टुंड्रा में तथा समुद्र अधस्तल के नीचे पाए जाते हैं।
- 3.वायुमंडल के अंदर मेथैन एक या दो दशक के बाद कार्बन डाइऑक्साइड में ऑक्सीकृत हो जाता है।
नीचे दिए गए कूट का प्रयोग कर सही उत्तर चुनिए।
Read this question in English
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
उत्तर और व्याख्या · explanation in English
Answer: (d) 1, 2 और 3
All three statements are correct. Methane hydrate is an ice-like solid holding methane, found in Arctic permafrost and in sea-floor sediments; it releases methane when it warms, and methane that reaches the air lasts about a decade before it is oxidised to carbon dioxide.
- ✓ 1. Methane hydrate is stable only at low temperature and high pressure. Warming makes the hydrate release its methane, which is why global warming could trigger releases.
- ✓ 2. Gas hydrates occur in huge quantities in marine sediments just below the sea floor and in association with permafrost in the Arctic.
- ✓ 3. Methane is short-lived in the air: it lasts about a decade on average (IPCC AR6 gives 11.8 years). It is broken down by oxidation, ending as carbon dioxide and water.
Remember · Methane hydrate = methane locked in ice-like crystals under permafrost and seabed. Warming can release it; airborne methane lasts about 12 years and then oxidises to CO2.
Sources
- US Geological Survey: Where are gas hydrates found? (Internet Archive copy) ↗ “it exists in huge quantities in marine sediments in a layer several hundred meters thick directly below the sea floor and in association with permafrost in the Arctic.”
- US Geological Survey: What are gas hydrates? (Internet Archive copy) ↗ “Gas hydrate is sometimes called “the ice that burns” because the warming hydrates release enough methane to sustain a flame.”
- US EPA: Understanding Global Warming Potentials ↗ “CH 4 emitted today lasts about a decade on average, which is much less time than CO 2 .”
- IPCC AR6 Working Group I, Chapter 7: lifetime of methane (Table 7.15) ↗ “Species Lifetime (Years) Radiative Efficiency (W m –2 ppb –1 ) GWP-20 GWP-100 GWP-500 GTP-50 GTP-100 CGTP-50 (years) CGTP-100 (years) CO 2 Multiple 1.33 ± 0.16 ×10 –5 1. 1.000 1.000 1.000 1.000 CH 4 -fossil 11.8 ± 1.8”
Question and answer: UPSC's official GS Paper I (2019, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·