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I am not asking about why the summer is hotter then the spring. I do understand that the body of water on the surface of Earth needs to cool off and warm up, and that takes more time then for the atmosphere. I am specifically asking why the temperature of the atmosphere is determined more by the bodies of water and ground in the winter then by the Sunlight itself.

I have read these questions:

Why don't solstices coincide with temperature extremes?

Why is the summer, in the temperate latitudes, in average, hotter that the spring?

where Jim says:

A major part of the reason for this is due to the temperature of the ground. Furthermore, it takes much longer to warm or cool a body of water than a mass of air; even longer to warm or cool the ground and water.

where tpg2114 says:

There is also the fact that the Earth's surface is 75% water and water is a giant heat sink. So coming off of the winter, the water stays cold for awhile and takes awhile to heat up. This is why spring is much cooler than fall. There is considerable lag between the peak heating and the hottest temperatures due to the ability of the oceans to store energy.

Based on these answers, the winter Solstice, Dec 21st, could still be determined by the Sunlight.

Ultimately it comes down to the power of Sunlight vs the power of the bodies of water and ground. And it seems like the bodies of water and the ground win.

But the Sunlight affects almost each and every particle inside the atmosphere directly through scattering, transferring the photons' energies directly to the molecules and heating them up.

Now the bodies of water and the ground only interact with the atmosphere at the lowest layer, but not inside the atmosphere.

So my reasoning is, that the Sunlight should be able to supersede (because Sunlight directly interacts with all layers of the atmosphere) the effects of the bodies of water and the ground and Sunlight should be the main cause and should mainly determine the temperature of the atmosphere.

Infrared radiation is popularly known as "heat radiation",[21] but light and electromagnetic waves of any frequency will heat surfaces that absorb them. Infrared light from the Sun accounts for 49%[22] of the heating of Earth, with the rest being caused by visible light that is absorbed then re-radiated at longer wavelengths. Visible light or ultraviolet-emitting lasers can char paper and incandescently hot objects emit visible radiation.

https://en.wikipedia.org/wiki/Infrared

Based on the comments, the light from the Sun heats more efficiently the solids and liquids on Earth, then the gases (atmosphere) directly, thus the energy from the Sunlight first transforms into the vibrational and rotational energies of the waters and the ground, and those heat up the air (because they are in direct contact with the air). Is this reasoning correct?

Question:

  1. Why doesn't the Sunlight supersede the effects of the bodies of water and the ground on the temperature of the atmosphere?
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    $\begingroup$ Sunlight does not heat the atmosphere. Sunlight is absorbed at the surface. This is what heats the surface, which heats the air. $\endgroup$ – Pieter Dec 4 '19 at 20:19
  • $\begingroup$ @Pieter sorry, but Sunlight includes infrared. "Infrared radiation is popularly known as "heat radiation",[21] but light and electromagnetic waves of any frequency will heat surfaces that absorb them. Infrared light from the Sun accounts for 49%[22] of the heating of Earth, with the rest being caused by visible light that is absorbed then re-radiated at longer wavelengths. Visible light or ultraviolet-emitting lasers can char paper and incandescently hot objects emit visible radiation. " en.wikipedia.org/wiki/Infrared $\endgroup$ – Árpád Szendrei Dec 4 '19 at 20:51
  • $\begingroup$ Have you looked at the Climatology section of the Infrared wikipedia page you linked to? It has a graphic showing the energy balance of where sunlight goes viz. atmosphere and ground, and also shows how much energy is radiated from the ground back up. $\endgroup$ – tpg2114 Dec 4 '19 at 21:04
  • $\begingroup$ @tpg2114 " Infrared light from the Sun accounts for 49%[22] of the heating of Earth" this is what confuses me. Does this mean that this infrared is just heating up the ground? So you are saying that infrared does not heat up the atmosphere or that its energy (heating directly the air) is negligible compared to it heating the ground? So basically the ground and water can be heated by infrared more efficiently then the air? $\endgroup$ – Árpád Szendrei Dec 4 '19 at 21:28
  • $\begingroup$ why the downvote? $\endgroup$ – Árpád Szendrei Dec 4 '19 at 21:36
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The sunlight heats the air only a negligible amount.

In response to one of your comments, temperature is defined by the kinetic energy of molecules (it also has an equivalent statistical definition in terms of multiplicities but I will not get into that), not by light wavelengths: infrared light is radiated by objects with a certain temperature range, but all wavelengths of light carry energy; the emitted lightwave radiated from "warm" objects depends on the temperature of the object. To say "the sunlight inlcudes infrared" means nothing in terms of heat: infrared light is not hot, it is light, it does not have a temperature. All wavelengths of light carry energy, and when they are absorbed, the absorbing particles gain kinetic energy and thus their temperature increases.

You know infrared is associated with heat because relatively cold objects (like animals) are at a temperature where the radiated lightwave is infrared. But hot objects radiate visible light when they become warm (like incandescent lightbulbs).

The air absorbs a negligible amount of light, but it does absorb certain (mainly non-visible) wavelengths. Especially because the air is not very dense compared to the ground, and because the ground absorbs visible light (higher energy than infrared) you can pretend that the air doesn't get warmed by the sun's light at all.

The end result is that the sun radiates energy, and radiation is absorbed which translates to an increase in temperature, and because air is not dense, the amount of energy absorbed is negligible compared the energy transfered to the air via conduction (the transfer of heat between the air and the ground when they are in physical contact). In addition, the transfer of heat to the ground via absorption of radiation from the sun is also significantly greater than the transfer of heat to the air via the absorbtion of radiation from the sun.

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  • $\begingroup$ "The air absorbs a negligible amount of light, but it does absorb certain (mainly non-visible) wavelengths. Especially because the air is not very dense compared to the ground, and because the ground absorbs visible light (higher energy than infrared) you can pretend that the air doesn't get warmed by the sun's light at all." I think this part is what should answer the question. $\endgroup$ – Árpád Szendrei Dec 4 '19 at 21:33
  • $\begingroup$ Now what is not clear, is that basically you are saying that (though 49% of the energy comes from infrared), infrared cannot efficiently heat the air directly, but light (including infrared and other wavelengths) can directly heat up the ground and the waters more efficiently? So basically it is because light can transfer its energy more efficiently to solids and liquids then gas? $\endgroup$ – Árpád Szendrei Dec 4 '19 at 21:34
  • $\begingroup$ But ultimately, the ground and the waters are in direct contact with the air, and this is how they warm the air in the end right? It is just that light heats solids and liquids more efficiently then gases? $\endgroup$ – Árpád Szendrei Dec 4 '19 at 21:36
  • $\begingroup$ @arpadszendrei on a small scale, light is absorbed by molecules. Solids and liquids absorb a lot of heat energy because they have are very dense compared to the air. The air is also transparent to visible light so it effectively only absorbs lower energy radiation (infrared). There are gases which have an easier time absorbing light radiation (think gases like smoke, which are opaque to visible light). The real dominating factor here is density: there are more molecules of "ground" in a given area than there are air molecules. $\endgroup$ – Vivid Kraig Dec 4 '19 at 21:45
  • $\begingroup$ The dominant scattering form of light with air is Rayleigh, elastic. That makes the sky blue. Elastic scattering is the only way for photons to keep their energy. That is why light (most of the visible) does not transform energy to the air. What I am asking is more of the infrared. But I guess your answer tells that too, infrared heats more the solids and liquids (you say it is density). Thank you If you like the question please upvote. $\endgroup$ – Árpád Szendrei Dec 4 '19 at 21:48

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