In the spring, changes in sunlight intensity warms the top layer of water, according to the Clean Lakes Alliance. The oxygen in the lake stays with the warm water, at the top of the lake in the summer and at the bottom in the winter.Īs seasons change, the temperature of the water at the lake's surface begins to change. In the summer and winter, the water in these lakes forms into layers, with warmer water, which is less dense, floating atop a layer of cooler, more dense water in the summer. Lake turnover typically occurs in lakes that are deeper than 20 feet, according to the Clean Lakes Alliance.
This seasonal change, called turnover, causes the water at the top and bottom of lakes to mix. All around us each spring and fall, our local lakes experience seasonal changes that go mostly unnoticed but are important to the health of all aquatic life within.