Climate change and decarbonisation — UPSC Prelims PYQs
40 questions in this bank come from Climate change and decarbonisation, spanning UPSC Prelims papers from 2011 to 2026. Every question here carries all four options, the correct answer and a full explanation.
It has appeared in 15 of the last 16 papers, most heavily in 2025 with 8 questions. That makes it one of the most dependable areas in the paper.
The themes examined most often within it are Environmental technologies and greenhouse gases (10), Economy and climate change impacts (5), Global climate change policies and frameworks (5), Effects of climate change on ecosystems and wildlife (3) and Innovative decarbonization strategies (3). Those counts are of questions in which the theme is examined, not merely mentioned.
Questions here are spread across Environment & Ecology (27), Geography (7), Economy (4) and Polity & Governance (1). Between them they draw on 52 distinct themes, so this is a broader area than a single revision note can cover. That is 2.8% of the 1433 questions in the bank — useful for deciding how much revision time it deserves.
It has come up more often lately — roughly 3.8 questions a year across the last five papers, against 1.9 before that.
It was not examined in 1 of those papers. Each question below links to its full explanation and to related questions on the same theme from other years, so a weak area can be worked through in one pass rather than hunted for paper by paper.
UPSC Prelims 20262 questions
- Environment & Ecology
Which of the following statements with regard to Green Hydrogen is/are correct? 1. It is decarbonized hydrogen obtained from natural gas reforming combined with carbon capture and storage (CCS). 2. It is produced using electrolysis of water with electricity generated by renewable energy. 3. National Green Hydrogen Mission of India aims for abatement of nearly 50 MMT of annual greenhouse gas emissions by 2030. Select the answer using the code given below:
- Environment & Ecology
Consider the following statements with reference to India's response to climate change: I. India's Long-Term Low Emission Development Strategy (LT-LEDS) is a crucial tool for achieving net-zero emissions by 2070. II. India's 4th Biennial Update Report (BUR-4) submitted in December, 2024 recorded around 8% decrease in Greenhouse gas emissions in 2020 over 2019. III. Climate-resilient development necessarily depends on quick and short-term achievement of emission reduction targets. Which of the following relationships among the above statements is/are correct? 1. Statement I is empirically supported by statement II. 2. Statement III contradicts the approach implicit in statement I. 3. Statement I and statement III together establish the premise of long-term sustainability. Select the answer using the code given below:
UPSC Prelims 20258 questions
- Geography
Consider the following statements: Statement I: Scientific studies suggest that a shift is taking place in the Earth's rotation and axis. Statement II: Solar flares and associated coronal mass ejections bombarded the Earth's outermost atmosphere with tremendous amount of energy. Statement III: As the Earth's polar ice melts, the water tends to move towards the equator. Which one of the following is correct in respect of the above statements?
- Environment & Ecology
With reference to 'Direct Air Capture', an emerging technology, which of the following statements is/are correct? I. It can be used as a way of carbon sequestration. II. It can be a valuable approach for plastic production and in food processing. III. In aviation, it can be a source of carbon for combining with hydrogen to create synthetic low-carbon fuel. Select the correct answer using the code given below.
- Economy
Consider the following statements: I. Without the atmosphere, temperature would be well below freezing point everywhere on the Earth's surface. II. Heat absorbed and trapped by the atmosphere maintains our planet's average temperature. III. Atmosphere's gases, like carbon dioxide, are particularly good at absorbing and trapping radiation. Which of the statements given above are correct?
- Environment & Ecology
Consider the following statements: Statement I: Studies indicate that carbon dioxide emissions from cement industry account for more than 5% of global carbon emissions. Statement II: Silica-bearing clay is mixed with limestone while manufacturing cement. Statement III: Limestone is converted into lime during clinker production for cement manufacturing. Which one of the following is correct in respect of the above statements?
- Geography
Consider the following statements: Statement I: In January, in the Northern Hemisphere, the isotherms bend equatorward while crossing the landmasses, and poleward while crossing the oceans. Statement II: In January, the air over the oceans is warmer than that over the landmasses in the Northern Hemisphere. Which one of the following is correct in respect of the above statements?
- Geography
Consider the following statements: Statement I: At the 28th United Nations Climate Change Conference (COP28), India refrained from signing the 'Declaration on Climate and Health'. Statement II: The COP28 Declaration on Climate and Health is a binding declaration; and if signed, it becomes mandatory to decarbonize health sector. Statement III: If India's health sector is decarbonized, the resilience of its health-care system may be compromised. Which one of the following is correct in respect of the above statements?
- Environment & Ecology
Consider the following statements: Statement I: Circular economy reduces the emissions of greenhouse gases. Statement II: Circular economy reduces the use of raw materials as inputs. Statement III: Circular economy reduces wastage in the production process. Which one of the following is correct in respect of the above statements?
- Economy
The World Bank warned that India could become one of the first places where wet-bulb temperatures routinely exceed 35 °C. Which of the following statements best reflect(s) the implication of the above-said report? I. Peninsular India will most likely suffer from flooding, tropical cyclones and droughts. II. The survival of animals including humans will be affected as shedding of their body heat through perspiration becomes difficult. Select the correct answer using the code given below.
UPSC Prelims 20244 questions
- Polity & Governance
Consider the following statements: Statement-I: The European Parliament approved The Net-Zero Industry Act recently. Statement-II: The European Union intends to achieve carbon neutrality by 2040 and therefore aims to develop all of its own clean technology by that time. Which one of the following is correct in respect of the above statements?
- Geography
One of the following regions has the world's largest tropical peatland, which holds about three years worth of global carbon emissions from fossil fuels; and the possible destruction of which can exert detrimental effect on the global climate. Which one of the following denotes that region?
- Economy
Consider the following materials: 1. Agricultural residues 2. Corn grain 3. Wastewater treatment sludge 4. Wood mill waste Which of the above can be used as feedstock for producing Sustainable Aviation Fuel?
- Environment & Ecology
Consider the following statements: Statement-I: The atmosphere is heated more by incoming solar radiation than by terrestrial radiation. Statement-II: Carbon dioxide and other greenhouse gases in the atmosphere are good absorbers of long wave radiation. Which one of the following is correct in respect of the above statements?
UPSC Prelims 20234 questions
- Environment & Ecology
Consider the following heavy industries: 1. Fertilizer plants 2. Oil refineries 3. Steel plants Green hydrogen is expected to play a significant role in decarbonizing how many of the above industries?
- Environment & Ecology
Consider the following: 1. Aerosols 2. Foam agents 3. Fire retardants 4. Lubricants In the making of how many of the above are hydrofluorocarbons used?
- Science & Technology
With reference to green hydrogen, consider the following statements: 1. It can be used directly as a fuel for internal combustion. 2. It can be blended with natural gas and used as fuel for heat or power generation. 3. It can be used in the hydrogen fuel cell to run vehicles. How many of the above statements are correct?
- Environment & Ecology
Consider the following activities: 1. Spreading finely ground basalt rock on farmlands extensively 2. Increasing the alkalinity of oceans by adding lime 3. Capturing carbon dioxide released by various industries and pumping it into abandoned subterranean mines in the form of carbonated waters How many of the above activities are often considered and discussed for carbon capture and sequestration?
UPSC Prelims 20221 question
UPSC Prelims 20211 question
UPSC Prelims 20201 question
UPSC Prelims 20192 questions
- Environment & Ecology
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 oxidised to carbon dioxide after a decade or two. Select the correct answer using the code given below.
- Environment & Ecology
In the context of which of the following do some scientists suggest the use of cirrus cloud thinning technique and the injection of sulphate aerosol into the stratosphere?
UPSC Prelims 20184 questions
- Environment & Ecology
“Momentum for Change: Climate Neutral Now” is an initiative launched by
- Environment & Ecology
Which of the following statements best describes “carbon fertilization”?
- Environment & Ecology
With reference to the ‘Global Alliance for Climate-Smart Agriculture (GACSA)’, which of the following statements is/are correct? 1. GACSA is an outcome of the Climate Summit held in Paris in 2015. 2. Membership of GACSA does not create any binding obligations. 3. India was instrumental in the creation of GACSA. Select the correct answer using the code given below:
- Geography
Which of the following has/have shrunk immensely/dried up the recent past due to human activities? 1. Aral Sea 2. Black Sea 3. Lake Baikal Select the correct answer using the code given below:
UPSC Prelims 20172 questions
- Environment & Ecology
With reference to ‘Global Climate Change Alliance’, which of the following statements is/are correct? 1. It is an initiative of the European Union. 2. It provides technical and financial support to targeted developing countries to integrate climate change into their development policies and budgets. 3. It is coordinated by World Resources Institute (WRI) and World Business Council for Sustainable Development (WBCSD). Select the correct answer using the code given below:
- Environment & Ecology
In the context of mitigating the impending global warming due to anthropogenic emissions of carbon dioxide, which of the following can be potential sites for carbon sequestration? 1. Abandoned and uneconomic coal seams 2. Depleted oil and gas reservoirs 3. Subterranean deep saline formations Select the correct answer using the code given below:
UPSC Prelims 20162 questions
UPSC Prelims 20153 questions
- Environment & Ecology
What is the Rio+20 Conference, often mentioned in the news?
- Geography
Consider the following statements: 1. The winds which blow between 30 N and 60 S latitudes throughout the year are known as westerlies. 2. The moist air masses that cause winter rains in North- Western region of India are part of westerlies. Which of the statements given above is/are correct?
- Environment & Ecology
Which of the following statements regarding ‘Green Climate Fund’ is/are correct? 1. It is intended to assist developing countries in adaptation and mitigation practices to counter climate change. 2. It is founded under the aegis of UNEP, OECD, Asian Development Bank and World Bank. Select the correct answer using the codes given below.
UPSC Prelims 20142 questions
- Environment & Ecology
The scientific view is that the increase in global temperature should not exceed 2°C above the pre-industrial level. If the global temperature increases beyond 3°C above the pre- industrial level, what can be its possible impact/impacts on the world? 1. Terrestrial biosphere tends toward a net carbon source. 2. Widespread coral mortality will occur. 3. All the global wetlands will permanently disappear. 4. Cultivation of cereals will not be possible anywhere in the world. Select the correct answer using the code given below:
- Environment & Ecology
Consider the following statements regarding ‘Earth Hour’ 1. It is an initiative of UNEP and UNESCO 2. It is a movement in which the participants switch off the lights for one hour on a certain day every year. 3. It is a movement to raise awareness about climate change and the need to save the planet. Which of the statements given above is/are correct?
UPSC Prelims 20123 questions
- Environment & Ecology
The increasing amount of carbon dioxide in the air is slowly raising the temperature of the atmosphere, because it absorbs
- Geography
The acidification of oceans is increasing. Why is this phenomenon a cause of concern 1. The growth and survival of calcareous phytoplankton will be adversely affected. 2. The growth and survival of coral reefs will be adversely affected. 3. The survival of some animals that have phytoplanktonic larvae will be adversely affected. 4. The cloud seeding and formation of clouds will be adversely affected. Which of the statements given above is/are correct?
- Environment & Ecology
Consider the following agricultural practices: 1. Contour bunding 2. Relay cropping 3. Zero tillage In the context of global climate change, which of the above helps/help in carbon sequestration/storage in the soil?
