UPSC Prelims 2023 · GS Paper I
Question 68: Environment and 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?
AnswerUPSC’s answer is (c).
All three are discussed in carbon dioxide removal and storage. Spreading finely ground basalt on farmland is enhanced rock weathering, which binds CO2 as carbonate minerals. Adding lime or other alkalinity to the ocean raises its capacity to absorb CO2. Capturing CO2 from industry and injecting it as carbonated water into basalt formations or abandoned mines turns it into stable minerals.
- 1. Spreading ground basalt is enhanced rock weathering.
- 2. Ocean alkalinity enhancement raises CO2 uptake.
- 3. Injecting carbonated water into rock or mines mineralises CO2.
How you could have got this
No shortcut here: in a “how many” question, ruling out options doesn’t help. Every statement has to be judged.
Which options go is worked out from UPSC’s key and the options, not by a model.
Why each option is right or wrong
- (a) Only one undercounts; all three are discussed methods.
- (b) Only two undercounts the discussed methods.
- (c) Correct: rock weathering, ocean alkalinity and mineral storage are all discussed.
- (d) All are real proposals, so not none.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2023, General Studies Paper I, Series A. The paper on upsc.gov.in.