- 20 Oct 2021 20:34
#15195101
What you prove below is that your scientific knowledge is rudimentary at best, and certainly far inferior to mine.
No. You incorrectly assumed that the absorption of downward radiation that prevents CO2 in the upper atmosphere from warming the earth's surface was absorption of visible wavelengths from the sun rather than IR wavelengths from CO2 in the air. GHGs warm the earth precisely BECAUSE they are transparent to visible wavelengths from the sun, but absorb infrared wavelengths emitted from the earth's surface. But they are just as effective at absorbing downward IR from farther up in the earth's atmosphere as they are at absorbing upward IR from the surface.
No, you are, and I will thank you to remember it.
Right, but the photons radiated in any direction but down can't warm the earth's surface, so they are not relevant to the notional mechanism whereby CO2 in the upper atmosphere could warm the earth's surface. No matter how many times an IR photon is absorbed and reradiated by CO2 in the upper atmosphere, unless it somehow reaches the earth's surface again, it eventually leaves for outer space, and CANNOT warm the earth's surface.
Incident solar radiation, most of it in visible wavelengths, gets back to outer space one of two ways: immediate reflection from the surface, especially from snow or ice, but also from land (the oceans are almost completely black, and absorb almost all incident EM radiation), or after being absorbed, thus heating the earth's surface, it is radiated from the surface as IR radiation that is absorbed and re-emitted many times by GHGs before finally reaching outer space.
When it makes molecules move faster, that IS heating.
No. This is all obvious, and I have never said or implied anything to the contrary.
It's not sent up more. It's just that it can only escape to outer space if it is not re-absorbed, and that is most likely if it goes up. But it is a simple geometric relationship: the greater the angle of emission is away from straight up, the greater the probability it will be reabsorbed. If it is emitted in any direction where the earth's surface is in the way, it CANNOT escape, and is certain to be reabsorbed before beginning the outward journey again.
It doesn't go up more than down. It just has a higher chance of escaping to outer space the closer it is to being emitted straight up, and NO chance of warming the earth's surface unless it is emitted in a downward direction that intercepts the earth's surface.
But only if it isn't reabsorbed before it reaches the surface! That is the point.
No, the concentration of CO2 actually increases slightly with altitude as water vapor condenses out. It is the density that decreases with pressure.
No, it does not. All it does is increase the altitude and reduce the temperature of the average final IR emission that escapes to outer space.
No. The equilibrium just shifts as described above. There is no continued build-up of heat such as you describe.
Yes, the earth is always out of thermal equilibrium and moving towards it.
Steve_American wrote:1] I disagree with your claiming more science knowledge that I have. See below for the proof.
What you prove below is that your scientific knowledge is rudimentary at best, and certainly far inferior to mine.
2] . a] Well, you may not have said that the energy that reaches the surface of the Earth from the sun is mostly in the form of visible light. However that is just a scientific fact. If you don't know this fact, then you are lacking in your scientific knowledge.
No. You incorrectly assumed that the absorption of downward radiation that prevents CO2 in the upper atmosphere from warming the earth's surface was absorption of visible wavelengths from the sun rather than IR wavelengths from CO2 in the air. GHGs warm the earth precisely BECAUSE they are transparent to visible wavelengths from the sun, but absorb infrared wavelengths emitted from the earth's surface. But they are just as effective at absorbing downward IR from farther up in the earth's atmosphere as they are at absorbing upward IR from the surface.
b] Well, again you're showing your lack of scientific knowledge.
No, you are, and I will thank you to remember it.
When a molecule absorbs heat=infrared light it doesn't reradiate it in the same direction. If it did it would have little effect as you say. However, the direction it is reradiated is totally random. So, is rediated down as much as up.
Right, but the photons radiated in any direction but down can't warm the earth's surface, so they are not relevant to the notional mechanism whereby CO2 in the upper atmosphere could warm the earth's surface. No matter how many times an IR photon is absorbed and reradiated by CO2 in the upper atmosphere, unless it somehow reaches the earth's surface again, it eventually leaves for outer space, and CANNOT warm the earth's surface.
. . . c] The GHG story is that the energy reaches the Earth's surface in the form of visible light from the sun. Over the course of a day or a year the energy either heats up the Earth or it is sent somehow back to space.
Incident solar radiation, most of it in visible wavelengths, gets back to outer space one of two ways: immediate reflection from the surface, especially from snow or ice, but also from land (the oceans are almost completely black, and absorb almost all incident EM radiation), or after being absorbed, thus heating the earth's surface, it is radiated from the surface as IR radiation that is absorbed and re-emitted many times by GHGs before finally reaching outer space.
Energy is conserved, it can't disappear. Either it leaves, or it heats things, or it makes something move faster.
When it makes molecules move faster, that IS heating.
. . . So, the infrared light is absorbed by CO2 in the air and reradiated up, down or sideways. If the energy is trapped at any altitude by any process it can't just be there. It must heat up the air at that altitude. This not happening much. We know this because we can feel the heat of the sun and so we know that it is enough to heat things up, like a piece of metal in the sun. Therefore, the fact that we don't see the temp of air at many altitudes heating up 2 dec. C per day, everyday, all summer, proves that the heat is mostly escaping out into space. And some is heating the ground and the oceans. But, mostly it must escape to space. It simply MUST! Again you are showing your lack of scientific knowledge.
No. This is all obvious, and I have never said or implied anything to the contrary.
. . . Lurkers, frankly I'm not sure why the infrared light tends to be sent up more but it must be because otherwise as I just showed it would either heat up the air or heat up the dirt & oceans.
It's not sent up more. It's just that it can only escape to outer space if it is not re-absorbed, and that is most likely if it goes up. But it is a simple geometric relationship: the greater the angle of emission is away from straight up, the greater the probability it will be reabsorbed. If it is emitted in any direction where the earth's surface is in the way, it CANNOT escape, and is certain to be reabsorbed before beginning the outward journey again.
He doesn't want to have it heat the dirt and we can agree it isn't heating the air that much, so it must go up more than down.
It doesn't go up more than down. It just has a higher chance of escaping to outer space the closer it is to being emitted straight up, and NO chance of warming the earth's surface unless it is emitted in a downward direction that intercepts the earth's surface.
. . . However, some can be sent back down to be causing the dirt to be heated a little year after year.
But only if it isn't reabsorbed before it reaches the surface! That is the point.
. . . Anyway, as we go up in altitude the concentration of CO2 is reduced as the air pressure is reduced.
No, the concentration of CO2 actually increases slightly with altitude as water vapor condenses out. It is the density that decreases with pressure.
Therefore, the level where the CO2 stops all the infrared rises, and this reduces the amount of the energy that finally escapes out into space.
No, it does not. All it does is increase the altitude and reduce the temperature of the average final IR emission that escapes to outer space.
So, less energy escapes, so more stays in the air or in the dirt/oceans/etc. And, that more energy must show up as heat, which we see as increasing temps. It isn't a lot, but the small change heats the Earth year after year.
No. The equilibrium just shifts as described above. There is no continued build-up of heat such as you describe.
BTW --- the Earth is never in temp. equilibrium because the temp does up and down during the day and during the months. The ave. temp. changes every year a little. Sometimes it has changed going down for decades, sometimes it has gone up a little each year for decades, and sometimes it has done little for decades, but it is always changing at least a little.
Yes, the earth is always out of thermal equilibrium and moving towards it.