That's not "waste" heat as far as the ecosystem is concerned. It creates the ocean thermocline which drives ocean currents and nutrient exchange between layers.

That's not "waste" heat as far as the ecosystem is concerned. It creates the ocean thermocline which drives ocean currents and nutrient exchange between layers. Without it everything in the ocean would starve from lack of basic minerals or suffocate due to lack of dissolved oxygen except around river deltas.