Unlike coal power plants which produce CO2 and intensify the greenhouse effect, every engine produces thermal pollution because of the constraints on engine efficiency. No engine can convert 100% of its heat input into work because doing so would violate the third law of thermodynamics. Thus, the extraneous heat (QL) can raise water and air temperatures. In the case of rivers, this could negatively affect aquatic life (warm water holds less O2).
However, how does raising air temperature affect the weather, and how is that process different than what is traditionally thought of as climate change from CO2? Does the output QL of every engine make the environment hotter? Is the same true for refrigerators and air conditioners which also output heat into the atmosphere?