Once the light strikes the earth, some of it is converted into heat waves, or the infrared spectrum. These wavelength are longer and more easily trapped.
Two different spectrum.
Hello Bob,
The heat that comes toward us from the Sun is in the form of solar radiation – it’s heat that is radiated out from the Sun. Because the Sun is so hot, these waves of energy are very energetic and they have a short wavelength.
This heat energy passes down through our atmosphere where some of it is absorbed by the ground (and all the things on it), which are then warmed up. Later in the day when the air cools down, this heat energy is radiated back out from those surfaces, only this time it’s coming from a much cooler source and so it has a longer wavelength. The incoming solar radiation has now been converted into outgoing thermal radiation.
The wavelength of the thermal radiation corresponds to the vibrational frequency of the molecules of greenhouse gases in the atmosphere. Because both are harmonised or in synch with one another, the greenhouse gas molecules can absorb the heat energy.
Some of this trapped heat is radiated back down to Earth and it’s this mechanism that we call the greenhouse effect. Some is lost into space and some is radiated out only to be absorbed by other greenhouse gas molecules.
As levels of greenhouse gases increase, more and more heat energy is being trapped in the atmosphere, this is what we refer to as global warming and the effects of this are referred to as climate change.
Supposedly because after it hits Earth it has a longer wave length which is harder to pass through CO2, however that is all nonsense the amount of heat retained would be incredibly minor, Greenhouses use glass which also restricts longer wave length energy, but if you ask any gardener they will tell you that greenhouses work by preventing convection, leave the doors open and they get pretty cold, same as closing you car windows, ie build of heat through loss of circulation/convection.
Nice question!
The sun is a giant fusion ball of hydrogen and helium gas. And it's hot - the surface is about 5000 degrees C and the core is about 15.7 million degrees! One of the golden rules of physics is that if you have a hot object it will emit electromagnetic radiation and, of course, the fusion process itself also produces electromagnetic radiation. The point is that if you have an object containing material ranging in temperatures from thousands to millions of degrees and undergoing fusion processes in the middle then that means the sun must produce electromagnetic radiation over a very broad range of energies. If we look at the sun we find it gives off very high energy gamma rays and X-rays. It also gives off lower energy electromagnetic radiation such as UV light, visible light, infra-red, and radio waves all of which we can detect with satellites.
The surface of the sun, at 5000 degrees, is the part that produces mostly visible light. This (along with the other energies of electromagnetic radiation) travels through the vacuum of space to the earth. Some of that visible light is scattered by the gases in our atmosphere, which is why the sky is blue in the day and red/orange in the mornings and evenings. Some of it is reflected from clouds or particles in the air. But a lot of the visible light reaches the ground and seas where it is absorbed.
The laws of physics tell us that if objects absorb energy they must get warmer. So objects on the ground or the oceans/seas themselves warm up as a result of sunlight falling on them. And, as we've already said, warm objects give off electromagnetic radiation. Clearly the roads, rocks and oceans aren't 5000 degrees like the surface of the sun, so they don't emit high energy electromagnetic radiation, but lower energies - what we call infra-red. Some of the gases in our atmosphere, like CO2, prevent certain energies of IR radiation from passing back into space so this energy warms our atmosphere.
SO ... the sun gives off a wide range of electromagnetic energies including visible light which can pass through our atmosphere and arrive at the ground. The objects on the ground absorbing this energy only heat up by a few tens of degrees which means they give off a narrow range of energies in the infrared. And some of the gases in our atmosphere prevent infrared passing back into space. It's the difference in energies between what comes in and what goes out that is why CO2 works like a one-way door!
Solar rays are not heat. They are radiation in several forms, light, infra-red radiation, ultra-violet radiation. As that radiation is absorbed by Earth and things on Earth, some of it is converted to heat. This is similar to nuclear reactors wherein the radioactive fuel rods basically boil water which in turn drives turbines and generates electricity.
The Sun emits a much wider portion than Earth does. Carbon dioxide does block some of the energy from the Sun, but that energy is a very small part of the Sun's spectrum.
Well the Sun's UV radiation passes through the CO2 and other greenhouses but the heat radiate back from earth is thermal radiation which is a different type of heat and gets bounced back
CO2 behaves like your car windows. On a sunny day, light gets through the glass, heat from inside the car cannot get out.
the rays from the sun are not 'heat' they are radiation- mostly visible light.
Excellent answer, Sagebrush.
This goes into more detail - http://www.skepticalscience.com/empirica...
This is a nice explanation of how it works.
http://oceanworld.tamu.edu/resources/oce...
I was thinking about the climate change theories that state that CO2 will trap heat inside the atmosphere preventing it from escaping, but i was wondering if CO2 blocks heat waves why wouldnt it stop solar rays from entering the atmosphre in the first place?
Everything is said to be CO2. It's misunderstood and balogny. It's best to stay natural only when natural is harmful.
