How is the energy that reaches earth's surface returned to space?
is is by radiation?
yes, it is reradiated.
Yes, a significant portion of the energy that reaches Earth's surface is indeed returned to space by radiation. This process is known as thermal radiation or infrared radiation. Here's an explanation of how it happens:
1. Incoming Solar Energy: The primary source of energy for Earth is the Sun, which emits electromagnetic radiation across a wide range of wavelengths, including visible light and infrared radiation.
2. Absorption by the Atmosphere and Earth's Surface: When solar radiation reaches Earth's atmosphere, it can be absorbed, scattered, or reflected. Some of it is absorbed by atmospheric gases, such as carbon dioxide and water vapor. The remaining energy reaches the Earth's surface.
3. Conversion to Heat: Upon reaching the surface, a significant portion of the solar energy is absorbed by land, water bodies, and vegetation. This absorbed energy is then converted into heat.
4. Thermal Radiation: Objects that have absorbed energy in the form of heat emit thermal radiation as a result of their temperature. This thermal radiation is typically in the form of infrared radiation.
5. Energy Transfer: The emitted infrared radiation from the Earth's surface interacts with greenhouse gases, such as carbon dioxide and water vapor, in the atmosphere. These greenhouse gases absorb and reradiate some of the outgoing heat energy back towards the Earth's surface.
6. Radiation to Space: However, a portion of the thermal radiation is not absorbed by greenhouse gases and instead escapes into space. This allows the Earth to maintain an energy balance over time and prevents overheating.
So, while some of the energy reaching Earth's surface is absorbed and retained through various processes like the greenhouse effect, a significant amount is ultimately returned to space through thermal radiation.