Examples of thermal pollution include the ways in which air and water become hotter as a result of artificial stimuli. One example is a lake overheating because of a nearby factory.
Thermal pollution arises when an artificial heat source enters an environment that cannot handle it. When this happens, the environment may become warmer than is normal for that time of year. This most often applies to the air and natural water sources. One example of this are factories. Many are located next to water sources and take cold water and replace it with hot water once they are finished with it. When that water source becomes warmer, it is no longer within the normal environmental range for the plants and animals that live there. As such, they may begin to decline. One way this decline happens is through thermal shock, which sometimes causes fish to die instantly. However, sometimes slightly warmer water can encourage plants to bloom.
Another example of heat energy and pollution is the burning of natural fuels. Burning wood leads to extra carbon dioxide in the air, and burning gas causes more nitrogen oxides to enter it. This disrupts the natural balance of gases in the air, which in turn is harmful to local environments.