Thermocline

No, there close no thermocline at the poles because there is almost no thermocline in polar waters due to the little amount of solar radiation at the poles.

The sun can't reach the thermocline layer to heat that depth of water

different types of micro organism are live thermocline.

A thermocline is a rapid change in temperature with depth in the ocean. Depending on the latitude and season, thermoclines can be present or absent and vary in depth of occurrence, however a thermocline will usually be found in the mesopelagic zone.