What is net longwave radiation?
Surface net long-wave radiation (L n ) represents the difference between the upward long-wave radiation emitted from the surface and the downward long-wave radiation from the atmosphere. It is the quantity of heat loss from the ground surface through L n exchange (Zhou et al. 1990).
What is another name for longwave radiation?
Outgoing Long-wave Radiation (OLR) is electromagnetic radiation of wavelengths from 3–100 μm emitted from Earth and its atmosphere out to space in the form of thermal radiation. It is also referred to as up-welling long-wave radiation and terrestrial long-wave flux, among others.
What is shortwave and longwave?
Short-wave infrared energy comes directly from the sun, but is not felt as heat. It converts into heat when it strikes an object. Long-wave infrared energy is the heat radiated from an object, which has received short-wave infrared radiation.
What is longwave downward radiation?
Downward longwave radiation is heat emitted back to Earth from the atmosphere and can change depending on the composition of the air.
Why is net radiation negative?
Net radiation, sometimes called net flux, is the difference between incoming solar radiation absorbed by the Earth’s surface and the radiation reflected back into space. Hence, an orange or red color indicates a greater (positive) net radiation, while a green or blue color indicates a lower (negative) net radiation.
Where is the highest net radiation on Earth?
For all surfaces, the net radiation is greatest when the sun is shining between clouds and is larger under an overcast sky than it is when the sun is near the horizon.
What has the greatest albedo on Earth?
Snow and ice have the highest albedos of any parts of Earth’s surface: Some parts of Antarctica reflect up to 90% of incoming solar radiation.
Why does longwave radiation increase at night?
Longwave radiation increases when water vapor condenses into droplets that radiate continuously over the whole longwave spectral range, including the 8-12 μm window in which water vapor does not radiate.
Why is solar radiation short wave?
The sun emits shortwave radiation because it is extremely hot and has a lot of energy to give off. Once in the Earth’s atmosphere, clouds and the surface absorb the solar energy. The ground heats up and re-emits energy as longwave radiation in the form of infrared rays.
Why is net radiation negative at night?
At night, the net radiation is usually a negative value as there is no incoming solar radiation and net long-wave is dominated by the outgoing terrestrial long-wave flux. The net radiation is zero when the incoming and outgoing components are in perfect balance, which doesn’t occur too often.
What is the net radiation budget of Earth?
Fortunately, the Earth has a global energy budget at approximately equilibrium, with a global net radiation at approximately zero (that is, global incoming energy equals global outgoing energy).
Where does the term longwave come from in radio?
In radio, longwave, long wave or long-wave, and commonly abbreviated LW, refers to parts of the radio spectrum with wavelengths longer than what was originally called the medium-wave broadcasting band. The term is historic, dating from the early 20th century, when the radio spectrum was considered to consist of longwave (LW),…
How are the wavelengths of longwave radiation measured?
The flux of energy transported by outgoing longwave radiation is measured in W/m². Over 99% of outgoing longwave radiation has wavelengths between 4 µm and 100 µm, in the thermal infrared part of the electromagnetic spectrum. Contributions with wavelengths larger than 40 µm are small, therefore often only wavelengths up to 50 µm are considered .
Where does long wave radiation come from in the atmosphere?
In the Earth’s climate system, long-wave radiation involves processes of absorption, scattering, and emissions from atmospheric gases, aerosols, clouds and the surface. Over 99% of outgoing long-wave radiation has wavelengths between 4 µm and 100 µm, in the thermal infrared part of the electromagnetic spectrum.
How is the flux of energy transported by outgoing long wave radiation?
The flux of energy transported by outgoing long-wave radiation is measured in W/m². In the Earth’s climate system, long-wave radiation involves processes of absorption, scattering, and emissions from atmospheric gases, aerosols, clouds and the surface.