ASKiIMAN™
NEXUS / 2024 / GS1
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UPSC 2024: Nexus 11—20

Atmospheric Moisture, Coriolis Geostrophy, Peatland Sinks & Fabaceae Phylogeny. [Set A]

Question 11

Aviation Infrastructure

Consider the following airports:

  1. Donyi Polo Airport
  2. Kushinagar International Airport
  3. Vijayawada International Airport

In the recent past, which of the above have been constructed as Greenfield projects?

Official Verdict: (a) 1 and 2 only

The Core Concept: A Greenfield airport project is built from scratch on previously undeveloped land, whereas a Brownfield project modifies or expands an existing aerodrome. Donyi Polo Airport (Hollongi near Itanagar, Arunachal Pradesh) was built completely anew on virgin land to connect the capital (1 is true). Kushinagar International Airport in Uttar Pradesh was developed from scratch as a major greenfield Buddhist pilgrimage gateway (2 is true). Vijayawada Airport (Gannavaram) is an old World War II airfield operational for decades; its recent terminal upgrades constitute brownfield expansion (3 is false).

Tethered to: REALM 99: Air Transport Infrastructure

1. Donyi Polo (Itanagar) ✅ • 2. Kushinagar ✅ 3. Vijayawada (Brownfield Expansion) ❌ Greenfield Civil Aviation
Altitude (km) 90% below 5 km (St 1 ✅) Negligible moisture in stratosphere Tropics = Max (4%) • Poles = Min (<1%) ❌

Question 12

Atmospheric Moisture Dynamics

With reference to "water vapour", which of the following statements is/are correct?

  1. It is a gas, the amount of which decreases with altitude.
  2. Its percentage is maximum at the poles.

Select the answer using the code given below:

Official Verdict: (a) 1 only

The Core Concept: Water vapor is a variable greenhouse gas that drops precipitously with altitude; over 90% of total atmospheric water vapor is concentrated within the first 5 km of the troposphere due to gravitational pooling and cold condensation temperatures above (Statement 1 is true). Statement 2 is completely inverted: warm air can hold vastly more moisture than freezing air (Clausius-Clapeyron relation). Consequently, water vapor peaks at up to 4% by volume in the warm, wet tropics and plummets to less than 1% over the frigid, dry polar regions.

Tethered to: REALM 73: Atmospheric Moisture

Question 13

Global Climatic Classification

Consider the following description:

  1. Annual and daily range of temperatures is low.
  2. Precipitation occurs throughout the year.
  3. Precipitation varies between 50 cm - 250 cm.

What is this type of climate?

  • (a) Equatorial climate
  • (b) China type climate
  • (c) Humid subtropical climate
  • (d) Marine West coast climate

Official Verdict: (d) Marine West coast climate

The Core Concept: Marine West Coast climate (Köppen's Cfb / British Type) is under permanent onshore oceanic influence from the prevailing Westerlies and warm ocean drifts. The ocean provides strong moderation, keeping both diurnal and annual temperature ranges remarkably low. Frontal cyclones deliver precipitation year-round without a distinct dry season, with rainfall ranging typically from 50 cm in rain-shadow lowlands to 250 cm on windward coastal ranges. Equatorial climates have much higher daily temperature ranges and heavy convective downpours that routinely exceed 200–300 cm.

Tethered to: REALM 84: Global Climate Systems II

Maritime Air Westerlies Cfb • Marine West Coast
Equator: sin(0°) = 0 • Force = 0 ✅ MAX Poles: sin(90°) = 1 ✅ Fc = 2vω sin(φ) • Proportional to v ✅ Geostrophic Balance

Question 14

Geophysical Fluid Dynamics

With reference to "Coriolis force", which of the following statements is/are correct?

  1. It increases with increase in wind velocity.
  2. It is maximum at the poles and is absent at the equator.

Select the answer using the code given below:

Official Verdict: (c) Both 1 and 2

The Core Concept: The Coriolis acceleration is mathematically expressed as $F_c = 2v\omega \sin\phi$, where $v$ is wind velocity, $\omega$ is Earth's angular rotation rate, and $\phi$ is latitude. Because $F_c$ is directly proportional to wind speed $v$, faster moving winds experience greater apparent deflection (Statement 1 is true). Because deflection depends on the sine of latitude, $\sin(0^\circ) = 0$ at the equator (rendering Coriolis force zero and preventing tropical cyclones from forming directly on the equator), whereas $\sin(90^\circ) = 1$ reaches its theoretical peak at the geographic poles (Statement 2 is true).

Tethered to: REALM 68: Winds & Forces

Question 15

Planetary Geometry & Solstice

On June 21 every year, which of the following latitude(s) experience(s) a sunlight of more than 12 hours?

  1. Equator
  2. Tropic of Cancer
  3. Tropic of Capricorn
  4. Arctic Circle

Select the correct answer using the code given below:

Official Verdict: (d) 2 and 4

The Core Concept: On the Summer Solstice (June 21), the Northern Hemisphere reaches its maximum axial tilt toward the Sun. Every latitude north of the equator experiences daylight exceeding 12 hours. At the Tropic of Cancer (23.5°N), sunlight lasts approximately 13.5 hours (2 is true). At the Arctic Circle (66.5°N), daylight lasts a continuous 24 hours ("Midnight Sun") (4 is true). At the Equator (0°), day and night remain split at exactly 12 hours year-round (1 is false). In the Southern Hemisphere (Tropic of Capricorn), winter solstice conditions prevail with less than 12 hours of light (3 is false).

Tethered to: REALM 07: Motions of Earth & Effects

Arctic (24 hrs) ✅ Cancer (>12 hrs) ✅ Equator (=12 hrs) Capricorn (<12 hrs) Summer Solstice Light Distribution
Cuvette Centrale 3 Years Global Fossil Carbon CONGO BASIN

Question 16

Global Biogeochemical Sinks

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?

  • (a) Amazon Basin
  • (b) Congo Basin
  • (c) Kikori Basin
  • (d) Rio de la Plata Basin

Official Verdict: (b) Congo Basin

The Core Concept: Groundbreaking satellite and field mapping by British and Congolese researchers uncovered the Cuvette Centrale peatland complex in the heart of the Congo Basin (straddling the Republic of the Congo and the Democratic Republic of the Congo). Covering an area larger than England, this swamp complex locks away an estimated 30 billion tons of carbon—equivalent to nearly three full years of total global fossil fuel emissions—making it the most carbon-dense tropical peatland complex on Earth.

Tethered to: REALM 54: Wetland Ecosystems

Question 17

Persistent Chemical Contaminants

With reference to perfluoroalkyl and polyfluoroalkyl substances (PFAS) that are used in making many consumer products, consider the following statements:

  1. PFAS are found to be widespread in drinking water, food and food packaging materials.
  2. PFAS are not easily degraded in the environment.
  3. Persistent exposure to PFAS can lead to bioaccumulation in animal bodies.

Which of the statements given above are correct?

Official Verdict: (d) 1, 2 and 3

The Core Concept: Known colloquially as "forever chemicals," PFAS compounds contain multiple carbon-fluorine bonds—one of the strongest chemical bonds in organic chemistry. Because they impart grease-, water-, and stain-resistance, they are ubiquitous in non-stick cookware, fast-food wrappers, firefighting foams, and waterproof clothing, subsequently contaminating municipal water supplies and food chains (1 is true). Because of their bond strength, they resist natural thermal, photolytic, and biological degradation (2 is true), persisting for decades and bioaccumulating in human and animal tissues (3 is true).

Tethered to: REALM 156: Persistent Organic Pollutants

Carbon-Fluorine (C-F) Bond FOREVER CHEMICALS Food Packaging • Water • Bioaccumulation
Beetles (1) • Flies (3) • Wasps (5) ✅

Question 18

Entomological Ecology

Consider the following:

  1. Carabid beetles
  2. Centipedes
  3. Flies
  4. Termites
  5. Wasps

Parasitoid species are found in how many of the above kind of organisms?

Official Verdict: (b) Only three

The Core Concept: A parasitoid is an organism whose larvae develop inside or on another host organism, ultimately killing the host in the process. Parasitoid species are widespread in three of these groups: Wasps (Hymenoptera, e.g., Ichneumonid and Braconid wasps used extensively in biocontrol); Flies (Diptera, e.g., Tachinid flies); and Beetles (Coleoptera, including specialized parasitic Carabid ground beetles like Lebia species). Centipedes are direct venomous predators, and Termites are eusocial detritivores/wood-feeders, neither exhibiting parasitoid lifecycles.

Tethered to: REALM 26: Biological Control

Question 19

Botanical Taxonomy

Consider the following plants :

  1. Groundnut
  2. Horse-gram
  3. Soybean

How many of the above belong to the pea family?

Official Verdict: (c) All three

The Core Concept: The pea family—scientifically classified as Fabaceae (or Leguminosae)—is characterized by butterfly-shaped (papilionaceous) flowers, root nodules hosting nitrogen-fixing Rhizobium bacteria, and fruit borne in pods (legumes). All three listed crops are quintessential members: Groundnut (Arachis hypogaea), Horse-gram (Macrotyloma uniflorum), and Soybean (Glycine max). All three belong to the Fabaceae family.

Tethered to: REALM 32: Pulses & Protein Crops

FABACEAE 1. Groundnut (Arachis) 2. Horse-gram (Macrotyloma) 3. Soybean (Glycine max) All 3 Belong to the Pea Family
Feeds on Blood ❌ (Frugivore!) DROPPED QUESTION (X)

Question 20

Wildlife Legislation & Ethology

Consider the following statements:

Statement-I:

The Indian Flying Fox is placed under the "vermin" category in the Wild Life (Protection) Act, 1972.

Statement-II:

The Indian Flying Fox feeds on the blood of other animals.

Which one of the following is correct in respect of the above statements?

Official Verdict: (X) Dropped Question

The Core Concept: UPSC officially dropped this question from scoring. Historically under the original Wildlife (Protection) Act 1972, fruit bats were listed under Schedule V (Vermin). However, the Wild Life (Protection) Amendment Act, 2022 (enforced from April 1, 2023) completely abolished Schedule V and restructured all schedules, rendering Statement-I legally ambiguous at the time of the 2024 exam. Statement-II is biologically false: the Indian Flying Fox (Pteropus giganteus) is exclusively a harmless frugivore (eating fruits and nectar), not a hematophagous vampire bat.

Tethered to: REALM 194: Wildlife Protection Law