Assertion (A) : The amount of moisture in the atmosphere is related to latitude. Reason (R) : The capacity to hold moisture in the form of water vapour is related to temperature.

Both statements are true and R correctly explains A. The capacity of air to hold water vapour depends primarily on temperature; warmer air can contain much more water vapour than colder air, so moisture‑holding capacity rises with temperature [2]. Because mean temperatures vary systematically with latitude (warmest near the equator, cooler toward the poles), the absolute and relative amounts of atmospheric moisture also vary with latitude — for example equatorial regions commonly show much higher relative humidity than polar regions [3]. Thus the latitudinal distribution of atmospheric moisture is a consequence of the temperature dependence of vapour capacity, making R the correct explanation of A.

Sources

1. [1] FUNDAMENTALS OF PHYSICAL GEOGRAPHY, Geography Class XI (NCERT 2025 ed.) > Chapter 10: Water in the Atmosphere > CHAPTER > p. 86
2. [2] Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 14: Climate > THE IMPORTANCE OF TEMPERATURE > p. 132
3. [3] Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 13: Weather > Notes > p. 120