epilimnia

/ˌɛpɪˈlɪmniə/
noun
  1. The upper, warm layer of water in a lake or reservoir, above the thermocline, where sunlight penetrates and mixing occurs.
    • Fish tend to gather in the epilimnia during warm months because the water is warmer and contains more food.
    • Scientists measured oxygen levels in the epilimnia to assess the health of the reservoir.
    • In summer, the epilimnia of temperate lakes become rich with algae and plant life.
Antonyms
What does "epilimnia" mean? | whatsthatwordmean | whatsthatwordmean