Where is thermocline the greatest?

The thermocline is typically greatest in tropical and subtropical regions, where there is a significant temperature gradient between the warmer surface waters and the colder deep waters. This layer is often more pronounced in oceanic areas with high sunlight penetration, which heats the surface layer, creating a stark contrast with the cooler, deeper waters. In contrast, polar regions may have little to no thermocline due to uniformly cold temperatures throughout the water column.