Assertion(A): Sea water is warmer than that of ofcean. Reason (R): Ocean receives more admixture of water from outside through the ocean currents.

Assertion (A) is true because enclosed or partially enclosed seas in low latitudes generally record higher temperatures than open oceans due to net heat gain and restricted water mixing [c1][c2]. Seas are often shallower and closer to landmasses, which heat up faster than deep ocean waters [c5]. Reason (R) is also true; oceans experience significant 'admixture' or mixing through global ocean currents and thermohaline circulation, which redistributes heat across vast distances and depths [c2][t6]. While this mixing in the open ocean prevents the extreme heat accumulation seen in enclosed seas, the reason provided (R) describes a general characteristic of ocean dynamics rather than the specific causal mechanism for why sea water is warmer. The temperature difference is primarily driven by the enclosed nature and shallower depth of seas compared to the vast, deep, and well-circulated open oceans [c1][t2].

Sources

1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 33: Ocean temperature and salinity > Factors Affecting Temperature Distribution of Oceans > p. 512
2. [2] FUNDAMENTALS OF PHYSICAL GEOGRAPHY, Geography Class XI (NCERT 2025 ed.) > Chapter 12: Water (Oceans) > Factors Affecting Temperature Distribution > p. 103
3. [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 21: Horizontal Distribution of Temperature > Land-Sea Differential > p. 286
4. [4] https://oceanexplorer.noaa.gov/ocean-fact/temp-vary/