deep lakes stratify..meaning there are thermoclines..or layers of water at different temperatures..I am SCUBA certified and dive some deep bodies of water..you may pass thru 1-2 of these thermal layers.
even lakes tha freeze will have warmer layers of water deeper.
these same bodies of watere will 'turn over' 1-2 times per year.
even lakes tha freeze will have warmer layers of water deeper.
these same bodies of watere will 'turn over' 1-2 times per year.
