Why do bodies of water make climate milder?

Question

Why do bodies of water make climate milder?

Answer 1

Water maintains it's temp a lot longer than soil.

Answer 2

Thermal inertia.  Water is very good at absorbing energy slwoly and giving it up slowly.  In addition to storing energy, water takes in or gives off energy as it changes phase, solid to liquid and liquid to vapor.

Answer 3

Water mixes more readily than rock so the air over water exchanges heat more easily. Thus the air over water is cooler in summer and warmer in winter (until the water freezes).

Answer 4

Warm air moving over water picks up moisture, and the heat of evaporation cools it off. Cold air moving over water has to take a tremendous amount of heat out of the water in order to freeze it.

The Pacific Northwest has another mechanism to keep the climate especially mild. In summer, the clockwise California current brings cold water southward along the coast. In autumn a little counterclockwise current near the tip of Baja California, called the Southern California Eddy, gradually gets stretched northward along the coast until it becomes the Davidson Curren, which brings warm water from Baja all the way to VanCouver Island in the winter. Consequently, the ocean temperature off the Washington Coast is only slightly colder in winter than it is in summer.