Cómo y por qué surge el arte contemporáneo?

The adjective contemporary works as a broad umbrella under the which everything what happened during the twentieth century has no place. And , in the case of art , the same thing happens. We refer to contemporary art when we talk about the artistic trends and styles that took on a special role in the different decades of the last century.

Explanation:

incident infrared radiation is blocked. visible and ultraviolet radiation heat   earth.

earth radiates infrared radiation. infrared radiation is blocked and heats earth. visible and shortwave radiation heat earth.

earth radiates longwave radiation

longwave radiation is reflected downward longwave radiation heats earth