Why does a thermocline form in the ocean?

A thermocline (also known as the thermal layer or the metalimnion in lakes) is a thin but distinct layer in a large body of fluid ( e.g. water such as an ocean or lake, or air, such as an atmosphere) in which temperature changes more rapidly with depth than it does in the layers above or below.

Why the planet stays in orbit is because of inertia (object stays in motion until a force changes it’s motion) also the atmosphere and gravity!

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