Question map
Not attempted Correct Incorrect ★ Bookmarked
Loading…
Q49 (CDS-II/2009) Geography › Indian Physical Geography › Indian rainfall patterns Answer Verified

Assertion (A) : Convectional rains occur during pre-monsoon summer in India. Reason (R) : Such rains occur due to adiabatic cooling.

Result
Your answer: —  Â·  Correct: A
Explanation

Assertion (A) is true as India experiences significant convectional rainfall during the pre-monsoon summer (March-May). These are locally known as Kal Baisakhi in West Bengal and Bordoisila in Assam, occurring due to intense surface heating [t3, t5]. Reason (R) is also true and provides the correct scientific explanation. Convectional rain is triggered when intense insolation causes air to expand and rise in vertical currents [t5]. As this air parcel ascends into layers of lower atmospheric pressure, it undergoes adiabatic cooling [c3, t5]. This cooling leads to condensation of water vapor, releasing latent heat which further drives the convection process and results in the formation of cumulonimbus clouds and subsequent rainfall [c3, c4]. Thus, adiabatic cooling is the fundamental thermodynamic mechanism that converts rising warm air into precipitation during these pre-monsoon convective events [t5].

Sources

  1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 22: Vertical Distribution of Temperature > A Parcel of Rising Air > p. 298
  2. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 24: Hydrological Cycle (Water Cycle) > Orographic Rainfall > p. 339
How others answered
Each bar shows the % of students who chose that option. Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
75%
got it right
✓ Thank you! We'll review this.

SIMILAR QUESTIONS

IAS · 2003 · Q113 Relevance score: 3.53

Assertion (A) : Areas lying within five to eight degrees latitude on either side of the equator receive rainfall throughout the year. Reason (R) : High temperatures and high humidity cause convectional rain to fall mostly in the afternoons near the equator.

IAS · 2001 · Q27 Relevance score: 3.40

Assertion (A) : Anti-cyclonic conditions are formed in winter season when atmospheric pressure is high and air temperatures are low. Reason (R) : Winter rainfall in Northern India causes development of anticyclonic conditions with low temperatures.

IAS · 1994 · Q37 Relevance score: 2.91

Assertion (A) : The monsoonal rainfall decreases as one goes towards the west and north-west in the Ganga plain. Reason (R) : The moisture-bearing monsoonal winds go higher up as one moves up in the Ganga plain. In the context of the above two statements which one of the following is correct ?

IAS · 1996 · Q42 Relevance score: 2.72

Assertion (A) : Areas near the equator receive rainfall throughout the year. Reason (R) : High temperatures and high humidity cause convectional rain in most afternoons near the equator. In the context of the above two statements, which one of the following is correct ?

IAS · 2004 · Q68 Relevance score: 1.59

Assertion (A) : Bangalore receives much higher average annual rainfall than that of Mangalore. Reason (R) : Bangalore has the benefit of receiving rainfall both from south-west and north-east monsoons.