Question

Why does the temperature of sea changes with the variation in depth? Write about thermal layers also.

Answer 1

Temperature increases with the variation in depth because pressure increases with depth and pressure is directly proportional to temperature therefore with increase in pressure there is increase in temperature.
Multiple layer of temperature in a system is called thermal layer

Answer 2

Because the sunlight cannot go bottom of the sea and the water temperature falls.
1 the sunlight zone (epipelagic zone)
2 twilight zone (Mesopelagic zone)
3 The midnight zone (Bathypelagic zone)
4 The abyss (abyssopelagic zone)
5 The trenches (hedalpelagic zone)