Illustration depicting Air-Sea exchanges

The sea surface loses heat via several different constantly occurring processes.

On a perfectly calm day, the ocean becomes like glass reflecting the world around it. It’s as if an identically opposite secret world hides below the ocean surface. On those days, the ocean absorbs heat from the sun, creating a thin layer of warm, buoyant water, perhaps just a few feet thick. It floats atop the ocean like oil floating on vinegar in salad dressing, separating the air from the deeper ocean.

Scientists have assumed that under calm conditions, this surface layer stays relatively stable and doesn’t mix with deeper waters. But new observations suggest that this may not be true. In this layer of warm water just below this apparently calm surface, a great deal is happening. The layer is swirling and churning, transferring energy to the deeper waters.