How does climate change affect water temperature?
Climate change cause an increase in water temperatures
Water temperatures (of rivers, lakes, estuaries, etc.) will, in many cases, increase due to global climate change. This means water pollutants will be more dissolved in water since temperature is one variable that affects solubility of materials in the environment.
In addition, dissolved oxygen in water will become lower when temperature of a water body increases. Oxygen-demanding water pollutants are substances that oxidize in the receiving body of water. As bacteria and other microscopic creatures decompose such wastes, they utilize oxygen dissolved in water, which reduces the remaining amount of dissolved oxygen (DO). As DO decreases, fish and other aquatic life are threatened and, in extreme circumstances, killed. Additionally, as DO concentration becomes lower, undesirable odors, tastes, and colors decrease the acceptability of that water body as a domestic water supply and drop its attractiveness for recreational uses. DO depends on water temperature. When water temperature increases, oxygen transfer from air to water decreases.
Another important point is that evaporation (from water bodies) will increase when air and water temperature increase. Therefore, there will be less water in a water body under this condition affecting pollutants.