Shortwave radiation is converted to longwave radiation through absorption and emission. When shortwave radiation, such as sunlight, hits an object, the object can absorb the radiation and convert it into heat. The object then emits this heat as longwave radiation, which is infrared radiation.

The atmosphere is transparent to shortwave radiation because the molecules in the atmosphere are much smaller than the wavelengths of shortwave radiation. As a result, the shortwave radiation can pass through the atmosphere without being absorbed.

However, the atmosphere is opaque to longwave radiation because the molecules in the atmosphere, such as water vapor and carbon dioxide, are about the same size as the wavelengths of longwave radiation. As a result, the longwave radiation is absorbed and scattered by the molecules in the atmosphere.

This property of the atmosphere is what causes the greenhouse effect. The greenhouse gases in the atmosphere absorb some of the longwave radiation emitted by the Earth's surface and then emit it back to the surface. This causes the Earth's surface to be warmer than it would be if there were no greenhouse gases in the atmosphere.

Here is an example of how shortwave radiation is converted to longwave radiation:

The greenhouse effect is essential for life on Earth. Without the greenhouse effect, the Earth's average surface temperature would be about -18 degrees Celsius (0 degrees Fahrenheit), which is too cold for most life to survive.

Dr Murtadha Shukur thank you for your contribution to the discussion

Sunlight (shortwave radiation) hits the Earth's surface. The Earth's surface absorbs the sunlight and converts it into heat. The Earth's surface then emits long wave radiation, which is infrared radiation. The long wave radiation is absorbed and scattered by the greenhouse gases in the atmosphere. Heat resulting from the absorption of incoming shortwave radiation is emitted as long wave radiation. Radiation from the warmed upper atmosphere, along with a small amount from the Earth's surface, radiates out to space. The earth's transparent for the infrared radiations of short wavelengths coming from the sun. The high energy radiations such as X rays, gamma rays, UV rays are absorbed by the ozone layer while the low energy radiations namely infrared radiations of long wavelength and radio waves are reflected back into the space. The energy received by the earth is known as incoming solar radiation which in short is termed insolation. The atmosphere is largely transparent to short-wave solar radiation. The incoming solar radiation passes through the atmosphere before striking the earth's surface. Sunlight, shortwave radiation, passes through the atmosphere. Earth's surface and atmosphere absorbs solar radiation and re-radiates it as long wave radiation. We feel this long wave radiation as heat.The Earth's atmosphere is transparent only to certain wavelengths of light that uses the analogy to open, closed, or partially closed windows. All visible light penetrates the atmosphere, most radio light penetrates the atmosphere, and some IR light passes through the atmosphere. Energy released from the Sun is emitted as shortwave light and ultraviolet energy. When it reaches the Earth, some is reflected back to space by clouds, some is absorbed by the atmosphere, and some is absorbed at the Earth's surface. Sunlight, shortwave radiation, passes through the atmosphere. Most of Earth's energy comes from the Sun. Shortwave solar radiation that's absorbed by Earth's surface or atmosphere is re-radiated it as long wave, infrared radiation, also known as heat. Clouds are a prime control of Earth's energy balance, as they scatter and absorb shortwave radiation originating from the sun, absorb long wave radiation emitted by Earth's surface and the cloud-free atmosphere, and themselves emit long wave radiation. Clouds are a prime control of Earth's energy balance, as they scatter and absorb shortwave radiation originating from the sun, absorb long wave radiation emitted by Earth's surface and the cloud-free atmosphere, and themselves emit long wave radiation.