This style, found almost nowhere else in Germany, uses dry straw and water reed to build the roofs, resulting in a home that is cool in the summer and warm in winter.

BBC: Exploring Germany��s northernmost island

The heating and cooling systems use air that has been earth-tempered drawn into a large tube and passed through the ground, which has a consistent temperature that is cool in the summer and warm in the winter.

BBC: The futurist: The sustainable Spaceport America

Experiments by Andrew Gallup at Princeton University, his father Gordon Gallup and a colleague found that yawning is suppressed by a cool pack strapped to the forehead or by summer temperatures that are higher then body temperature, and that therefore the purpose of yawning may be to cool the brain by inhaling air.

WSJ: Matt Ridley on Why You Just Yawned | Mind & Matter

By tapping that temperature, Fort Knox can keep cool on hot summer days and warm up in the dead of winter.

FORBES: Fort Knox's Buried Treasure

The air that swept across the parched inland prairie was soft and cool, with just a hint of the humidity that soaks Florida in the summer months.

BBC: Florida��s newest wildlife refuge

You'd think that cool soups, pastel-pale or jewel-bright, would be everybody's fallback food for summer.

NPR: Summer Soups: A Cool Quartet