Q1.
Assertion (A): Tropical cyclones do not originate at the equator.
Reason (R): The Coriolis force is negligible at the equator.
A. Both A and R are correct and R explains A
B. Both A and R are correct but R does not explain A
C. A is correct but R is incorrect
D. A is incorrect but R is correct
Answer: A
Explanation:
- Tropical cyclones require rotational force (vorticity) to develop a cyclonic circulation.
- Coriolis force provides this rotation but is zero at 0° latitude and increases poleward.
- Hence, cyclones typically form beyond 5° latitude, making R the correct explanation of A.
Q2. Which of the following conditions are essential for the formation of tropical cyclones?
- Sea surface temperature of at least 27°C
- Strong vertical wind shear
- Upper-level divergence in the troposphere
- Pre-existing low-pressure disturbance
Select the correct answer:
A. 1, 3 and 4 only
B. 1 and 2 only
C. 2, 3 and 4 only
D. 1, 2, 3 and 4
Answer: A
Explanation:
- Warm SST (≥27°C) provides moisture + latent heat energy.
- Pre-existing disturbance acts as a seed for cyclogenesis.
- Upper-level divergence helps remove rising air, maintaining low pressure.
- High vertical wind shear disrupts vertical structure, hence it is unfavourable.
Q3. Match the Following
| List-I (Feature) | List-II (Characteristic) |
| 1. Eye | A. Zone of maximum wind speed |
| 2. Eyewall | B. Region of lowest pressure and calm conditions |
| 3. Spiral rain bands | C. Bands of intense convection and rainfall |
Codes:
A. 1–B, 2–A, 3–C
B. 1–A, 2–B, 3–C
C. 1–C, 2–A, 3–B
D. 1–B, 2–C, 3–A
Answer: A
Explanation:
- Eye: Calm, subsiding air → lowest pressure, minimal winds.
- Eyewall: Surrounding ring of intense convection → highest wind speeds and rainfall.
- Spiral bands: Organized cloud bands → heavy precipitation zones extending outward.
Q4.
Which of the following oceanic regions is least conducive to tropical cyclone formation?
A. Bay of Bengal
B. Caribbean Sea
C. Western Pacific Ocean
D. South Atlantic Ocean
Answer: D
Explanation:
- South Atlantic has unfavourable conditions:
- Lower sea surface temperatures
- High vertical wind shear
- Weak pre-existing disturbances
- In contrast, other regions are major cyclone breeding zones due to warm waters and conducive atmospheric dynamics.
Q5.
The primary source of energy that sustains and intensifies tropical cyclones is:
A. Sensible heat from ocean surface
B. Latent heat released during condensation
C. Direct absorption of solar radiation
D. Heat from ocean floor (geothermal energy)
Answer: B
Explanation:
- Warm ocean water leads to evaporation → moist air rises.
- During condensation, latent heat is released, warming the core and lowering pressure further.
- This creates a positive feedback loop, strengthening the cyclone.
- Hence, tropical cyclones are classified as warm-core systems.
