Division of water into three layers, each of a different temperature, is referred to as:

• A. Thermal stratification
• B. Hydrological layering
• C. Thermal layering
• D. Water column separation

Answer: (A)

The phenomenon of dividing water into three layers, each at a different temperature, is known as thermal stratification. This occurs in bodies of water, such as lakes, during warmer months when sunlight warms the surface layer, creating a distinct temperature gradient between the cooler, denser water at the bottom and the warmer water on the surface.

In thermal stratification, the temperature differences can influence various biological and chemical processes within the water body, as well as affect environmental factors such as oxygen levels and nutrient distribution. This layering is important for understanding aquatic ecosystems and can influence the water treatment processes as well.

Other terms like hydrological layering, thermal layering, or water column separation may describe aspects of water stratification or layering but do not specifically capture the essence or the mechanism of temperature-based separation. Each of these alternative terms may imply a broader or different context but lack the precise definition that thermal stratification provides in the context of temperature differences in water bodies.