​Thermal energy can be transferred between substances as the flow of heat transfers through the water. Heat transfer, coming from either the air, sunlight, or thermal pollution can change the temperature of the water. Considered alone, the water temperature can affect the metabolic rates and biological activity of aquatic organisms. There aren’t any specific advantages or disadvantages to having a warm or cold water system because they both have their positives and negatives. Different water organisms have distinct preferred ranges of temperatures in which they can live, thrive, and reproduce. Water temperature is an important factor to consider when assessing water quality and the health of a river. Temperature influences several other parts of life in a body of water and can alter the physical and chemical properties of this water. Variables like turbidity, benthic, and dissolved oxygen have been discussed on the other variable sites.