Q52 (CDS-I/2006) Geography › World Physical Geography › Ocean water properties Answer Verified

Assertion (A): The salinity of oceans is relatively higher near the equator than at other regions. Reason (R): Equator region has heavy rainfall, high relative humidity and calm air.

Both A and R are individually true and R is the correct explanation of A

Both A and R are individually true but R is not the correct explanation of A

A is true but R is false

A is false but R is true

Result

Your answer: — · Correct: D

Explanation

The Assertion (A) is false because the salinity of oceans is actually lower near the equator compared to the subtropical regions. While the equator experiences high temperatures, the average salinity is approximately 35 parts per thousand, whereas the highest salinity (around 37) is found in the subtropical high-pressure belts between 20° and 30° N and S [2]. The Reason (R) is true and correctly describes the equatorial climate: it is characterized by heavy rainfall, high relative humidity, and the calm air of the doldrums [2]. This high precipitation and humidity lead to a net gain of fresh water, which dilutes the seawater and reduces its salinity [3]. Therefore, the conditions described in the Reason are the very factors that make the Assertion false, as they prevent the equator from having the highest salinity levels.

Sources

[1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 33: Ocean temperature and salinity > Atlantic > p. 519
[2] Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 12: The Oceans > Salinity of the Ocean > p. 107
[3] FUNDAMENTALS OF PHYSICAL GEOGRAPHY, Geography Class XI (NCERT 2025 ed.) > Chapter 12: Water (Oceans) > SALINITY OF OCEAN WATERS > p. 104

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Assertion (A): The salinity of oceans is relatively higher near the equator than at other regions. Reason (R): Equator region has heavy rainfall, high relative humidity and calm air.

Explanation

SIMILAR QUESTIONS

Assertion (A) : Despite low evaporation and stable stratification of the atmosphere, salinity is high in polar regions. Reason (R) : Sea water freezes leaving the remaining water saline than before.

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.

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 ?

Assertion (A) : The Equatorial regions bulge outwards by about 21 kilometre compared to Poles. Reason (R) : Earth’s slow rotation reduces the effect of gravity around the Equator.

Assertion (A) : 60°-65° latitudes in both the hemispheres have a low pressure belt instead of high pressure. Reason (R) : The low pressure areas are permanent over oceans rather than on land.