Hence, we say that heat rises away from the pull of gravity. In other words hotter molecules, moving faster than slower ones, push their neighbors aside to create a less dense and lighter parcel. Colder, slower moving ones are more dense and fall downwards toward the pull of gravity and set up a circulation pattern. Radiation is an oscillating strength of electromagnetic waves creating a movement in distant electrical and magnetic fields. Thus radiation can transfer energy without the need of a medium.
Radiation is in all directions.
Latent heat released from condensing water vapor helps to circulate the energy from the equatorial regions to the polar regions. Advection is a lateral movement of air. According to Wein's Law, the shorter the wavelength, the greater the energy. Explain how the earth's atmospheric greenhouse effect works. Certain gases mainly water vapor and carbon dioxide are selective absorbers of long infrared radiation.