UPSC Essentials | Daily subject-wise quiz : Environment and Geography MCQs on effects of the oil spill on marine life, Subansiri River basin and more (Week 129)

How many of the statements given above are correct?

(a) Only one

(b) Only two

(c) All three

(d) None

Explanation

— The sinking of the Liberian-flagged container vessel MSC ELSA 3 off the Kerala coast in May this year caused significant ecological disruption, an investigation report submitted by the Ministry of Earth Sciences (MoES) has found.

— Oil destroys the insulating ability of fur-bearing mammals, such as sea otters, and the water repellency of a bird’s feathers, thus exposing these creatures to the harsh elements. Without the ability to repel water and insulate from the cold water, birds and mammals will die from hypothermia. Hence, statement 1 is correct.

— Dolphins and whales can inhale oil, which can affect lungs, immune function and reproduction. Many birds and animals also ingest oil when they try to clean themselves, which can poison them. Hence, statement 2 is correct.

— Fish, shellfish, and corals may not be exposed immediately, but can come into contact with oil if it is mixed into the water column — shellfish can also be exposed in the intertidal zone. When exposed to oil, adult fish may experience reduced growth, enlarged livers, changes in heart and respiration rates, fin erosion, and reproduction impairment. Hence, statement 3 is correct.

Therefore, option (c) is the correct answer.

(Other Source: oceanservice.noaa.gov)

QUESTION 2

In India, the Subansiri River basin spreads over:

1. Arunachal Pradesh

2. Sikkim

3. Assam

4. Meghalaya

Select the correct answer using the codes given below:

(a) 1, 2 and 3

(b) 3 and 4 only

(c) 2 only

(d) 1 and 3 only

Explanation

— An expert panel of the Union Environment Ministry has approved environmental permission for the 2,220 MW Oju hydropower project proposed on the Subansiri River in Taksing, close to the Chinese border. It is at the top of a line of hydroelectric projects planned for the Subansiri basin and will be the largest in terms of permitted capacity.

— The Subansiri basin spans sections of Tibet (China), Arunachal Pradesh, and Assam in India, beginning in Tibet and flowing through Arunachal Pradesh before entering Assam’s plains and joining the Brahmaputra.

Therefore, option (d) is the correct answer.

QUESTION 3

Achanakmar Tiger Reserve (ATR) was recently in the news. It is located in:

(a) Odisha

(b) Chhattisgarh

(c) Jharkhand

(d) Telangana

Explanation

— In 2018, Jhumri traversed swathes of fragmented forests, hilly terrain and human inhabitations to stake claim on the sal and bamboo forests of Chhattisgarh’s Achanakmar Tiger Reserve (ATR). That 400-kilometre journey by the tigress, from Madhya Pradesh’s Bandhavgarh to ATR, was transformative for the reserve — it infused new life into its tiger conservation programme.

— ATR’s tiger population is thriving, up to 18 – 10 adults and eight cubs — from the five recorded in 2022. According to officials, much of this is down to conservation efforts, spurred on since Jhumri’s arrival.

— These included short-term efforts such as increased patrolling and aggressive — even reward-based — monitoring, and long-term ones such as creating sufficient artificial waterholes and creating super grasslands for the animals.

Therefore, option (b) is the correct answer.

QUESTION 4

With reference to the tropical cyclones, consider the following statements:

1. Tropical cyclones form over warm ocean waters near the equator.

2. The strongest tropical cyclones are called tropical depressions.

3. The category of a tropical cyclone is determined by the amount of rainfall it produces.

How many of the statements given above are correct?

(a) Only one

(b) Only two

(c) All three

(d) None

Explanation

— Super Typhoon Ragasa battered Hong Kong with fierce winds and pounding rain, and headed into southern China. The storm is the most intense tropical cyclone recorded in 2025. At its peak, Ragasa was moving with the maximum sustained winds of 280 kmph. This was close to the upper limit of how intense storms can be on Earth.

— Tropical cyclones form over warm ocean waters near the equator. When the warm, moist air from the ocean surface rises upward, a lower air pressure area is formed below. Air from surrounding areas with higher air pressure rushes into this low-pressure area, eventually rising, and it becomes warm and moist. Hence, statement 1 is correct.

— As warm, moist air rises, it cools down, and the water in the air forms clouds and thunderstorms. This whole system of clouds and winds gains strength and momentum using the ocean’s heat, and the water that evaporates from its surface.

— “The weakest tropical cyclones are called tropical depressions. If a depression intensifies such that its maximum sustained winds reach 39 miles per hour [63 kmph], the tropical cyclone becomes a tropical storm,” according to the National Oceanic and Atmospheric Administration (NOAA). Storm systems with wind speeds of 119 kmph and above are classified as hurricanes, typhoons, or tropical cyclones. Hence, statement 2 is not correct.

— The category of a tropical cyclone is determined by its sustained wind speed, as measured by the Saffir-Simpson Hurricane Wind Scale. It is classified into five categories — Category 1 to Category 5. Hence, statement 3 is not correct.

Therefore, option (a) is the correct answer.

QUESTION 5

With reference to the Nationally Determined Contributions (NDCs), consider the following statements:

1. NDCs embody efforts by each country to reduce national emissions and adapt to the impacts of climate change.

2. In its first NDC, India had promised to reduce its emissions intensity by 33 to 35 per cent from 2005 levels by 2030.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

Explanation

— India is likely to release an updated climate action plan during, or just ahead of, the COP30 climate meeting in Brazil in November, government sources said.

— Countries have to update their existing climate action plans, called Nationally Determined Contributions, or NDCs, in the language of the 2015 Paris Agreement, with a new set of targets to be achieved by the year 2035. The existing NDCs contain climate targets for the 2030 time-frame.

— NDCs embody efforts by each country to reduce national emissions and adapt to the impacts of climate change. Hence, statement 1 is correct.

— In its first NDC, India had promised to reduce its emissions intensity by 33 to 35 per cent from 2005 levels by 2030, and to ensure that at least 40 per cent of its installed electricity generation capacity in the year 2030 came from non-fossil fuel sources. In its second NDC, submitted in 2022, India had made an upward revision in both these targets. Hence, statement 2 is correct.

Therefore, option (c) is the correct answer.

(Other Source: unfccc.int)

Previous Daily Subject-Wise-Quiz

Daily Subject-wise quiz — History, Culture, and Social Issues (Week 124)

Daily subject-wise quiz — Polity and Governance (Week 129)

Daily subject-wise quiz —  Science and Technology (Week 129)

Daily subject-wise quiz — Economy (Week 129)

Daily subject-wise quiz — Environment and Geography (Week 128)

Daily subject-wise quiz – International Relations (Week 128)

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