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Discussion > Keeping it simple

If a body raised from an energy state E1 to energy state E2 then:

E2 - E1 = Q - W

Where Q = heat transfer and W = work.

First law of thermodynamics..

Also RR the universe can't get to 0K because energy cannot be created, or destroyed. Hadn't thought about what it would be in the limit, but currently outer space is at 3K, so one has to assume when all the energies from all the galaxies has evened out with space it must me a number higher than 3K. Could be wrong though, am taking long neglected knowledge off the shelf and dusting it.

Mar 8, 2017 at 3:27 PM | Unregistered Commentergeronimo

Which part of what I have written violates any part of such definitions?
None of it. But, then, you are not reading what I have written, either. The impression that you are giving in your postings about this energy being received is that it is NEW energy; energy that would not have existed were it not for … something (exactly what that might be is not clear, but then, it wouldn’t be, as that is really not your intention. Oh, the spin on this is getting weird!). For that energy to be received by your hand, spectrometer or whatever it is you might want to use, energy is LOST from the ground – i.e. your photon has retracted the work it had done on the ground, and is now applying it to your hand. Have a re-read of your comments; the benefit of time may have clouded your original thoughts, and allow you to see what others can see – you do not make it clear in your comments that the work this photon is doing is work that it has withdrawn from the ground; thus, the intimation is that it is NEW work.

I am not the only one who reads your comments thus, which is why you are getting such responses. I have entered the fray in an attempt to defend you, and to point out that you may be giving the wrong impression, and you really ought to change the tack of your argument.

Mar 8, 2017 at 3:57 PM | Registered CommenterRadical Rodent

I cannot be responsible for the false impression my posts may give to those who don't read them with sufficient care or who attach to them interpretations that were not their. The use of the word "re-radiation" should have given sufficient warning of my meaning. I must say that in trying to argue against me you sometimes write physics nonsense - what is " [the] photon has retracted the work it had done on the ground, and is now applying it to your hand"? Where can I read this in a physics text?

I asked repeatedly for you to point out where I state the energy is new? How about telling me where I gave even the slightest hint of this?

Mar 8, 2017 at 4:16 PM | Unregistered CommenterSupertroll

Where can I read this in a physics text?
That’s simple: you can’t. I was merely trying to follow your lead, when you were talking about photons working: “…those photons are not emitted or have no power to do work…” (Mar 8, 2017 at 4:25 AM.) Hence, I have tried to always enclose the word with quotation marks. It is a reference to the energy involved – in this scenario, the energy has been received from the Sun; when the Sun has been removed (i.e. it has set), there is no more generation of energy. The photon that is “working” (i.e. warming), as you describe it, is doing so by withdrawing heat energy from the surface for redistribution. It does not do any new warming; it is merely redistributing heat that is already there. Your heroic photon will bounce from surface to surface – heating it on arrival, cooling it on departure – until it eventually is released into space. When the Sun rises, and the cycle continues, your photon may continue its journey, though it will now be battling against a tide of new, fresh photons, none of which is aware of the travails which it may have to endure, and all may just laugh at your tired, worn-out, exhausted photon as they whiz past. Poor thing.

Mar 8, 2017 at 5:18 PM | Registered CommenterRadical Rodent

@ Mar 8, 2017 at 9:55 AM | Registered CommenterRadical Rodent

RR. Much better than I have put it. Thank you.

Once past that hurdle, the next question: if re-radiated energy is not further warming, what is it doing?

Mar 8, 2017 at 5:36 PM | Unregistered Commenterssat

Ahah. Now I see your problem. You are considering the whole system so that the warming of my hand is matched by an equivalent loss of heat from the ground, whereas I was considering the effect of upward radiating photons on my hand. We can agree that 1) all the energy comes from the Sun, 2) some of this energy is absorbed and heats the irradiated surfaces, 3) some of the photons absorbed by this heated surface are re-radiated. Where we may still differ, although I don't know why, is that this low grade emitted energy on its transit can do work. That work, indirectly, is still a consequence of the Sun's emissions. O.k. now?

RR you had to go back to March 2016!!! Yet you were objecting to what I was writing this week. I presume you found nothing recently written (nor actually in March 2016) that implied I was envisioning new energy (coming into existence somehow). If I remember correctly everyone was trying to convince me that those escaping IR photons could do no work, whereas the in the very act of escaping to space, they are doing work (look at the definition of work again, or see geronimo's contribution).

Mar 8, 2017 at 6:18 PM | Unregistered CommenterSupertroll

Please read my comment again, Minty – I was referring to a comment you made on the previous page, not 2016.

I think that people are trying to convince you that the IR photons can do no EXTRA work; these photons are merely doing work that they have “extracted” from other surfaces – what “work” they are doing is just spreading the “work” that has already been done.

Yes, we are talking at cross purposes, but, if we cannot get our point over to those with whom we are in general agreement, how much more difficult is it to get that point over to those who are actively in disagreement.

Mar 8, 2017 at 6:46 PM | Registered CommenterRadical Rodent

Again, did I ever mention extra work? - that's your and ssat's take on what I wrote. I wrote escaping photons can do work (heat my hand). It was you (and others) who at different times either denied this or wrote that it was not important. Let's leave this, as far as I can work apart from this we are in full agreement.

Mar 8, 2017 at 7:24 PM | Unregistered CommenterSupertroll

Radical rodent

Try a thought experiment.

Empty your garden water butt.

Run water into the top from a hose and open the tap at the bottom until slightly more water enters than leaves.

Go and have a cup of tea.

When you come back the volume and the head of water will have stabilised at such a level that the extra pressure has increased the outflow from the tap to match the inflow from the hose.

Close the outflow tap slightly. The head of water will increase because the outflow has decreased. It will stabilise when the pressure has increased enough to increase the outflow to its previous rate.

No water was created during this experiment.


Now scale it up to the climate system.

Water is energy. The flow in the hose is insolation. The volume of water in the tank is the total energy content. The head of water is temperature. The flow in the tap is outward radiation.

When the greenhouse effect is constant, heat content and temperature remain constant. When the greenhouse effect strengthens, outward radiation decreases; temperature and heat content increase.

No energy was created during this global warming.

Mar 8, 2017 at 7:31 PM | Unregistered CommenterEntropic man

Once past that hurdle, the next question: if re-radiated energy is not further warming, what is it doing? Mar 8, 2017 at 5:36 PM | Unregistered Commenter ssat

Maintaining the status quo. That is the (average) temperature of the surface and above, the hydrological cycles, the weather... and, very importantly, the atmospheric volume and its characteristics.

Mar 8, 2017 at 8:13 PM | Unregistered CommenterBelle Epoque

Well, we already know that the “greenhouse effect” is NOT constant, EM, else we would not have had a little ice age, or a mediæval warm period, or a dark age, or a Roman warm period, etcetera, etcetera… so… what is your point? Who was controlling the outlet tap, then?

Anyhoo… it is more probable that it is variation of the inflow of water that is more likely to be the controlling factor of the water level, if your “thought experiment” is to be a proper analogy for global temperatures. And, at present, the inlet tap has been turned down to minimum. Oooo, dear. Let’s just hope that your idea that CO2 is controlling the outlet tap is right… Sadly, I fear you are wrong.

Mar 8, 2017 at 8:14 PM | Registered CommenterRadical Rodent

Radical rodent

Remember that the greenhouse effect is not the only variable. There are several others which affect inflow and/or outflow.

Increasing albedo from industrial pollution or volcanoes acts to reduce Insolation. This is equivalent to reducing the inflow of water. Changes in the solar cycle raise and lower the inflow over an 11 year cycle.

On a 100,000 year timescale Milankovich cycles raise and lower effective Insolation.

I see the RWP, MWP and LIA as part of the same 5000 year Milankovich cooling trend, a gradual reduction in water inflow.

The two main influences on outflow are the greenhouse effect and cloud cover.

"at present, the inlet tap has been turned down to minimum"

Data, please.

Mar 8, 2017 at 11:31 PM | Unregistered CommenterEntropic man

Well done – you have managed to name some of the factors that actually cause the variations of the “greenhouse effect,” yet declare that they are different from the “greenhouse effect.” *facepalm*

You surprise me that you have not heard that the solar cycle is at a minimum… but, then, perhaps I should not be surprised – you have long refused to acknowledge any facts that conflict with your beliefs (which is also why I am not bothering with any links, as you are unlikely to bother actually following them). Ah, well, at least you acknowledge that the RWP, MWP and LIA existed; now, consider the cycles that these reveal, why is the present slight rise not part of that cycle? Oh – no, no, don’t tell me! – is it because this time, it’s humans wot ‘ave caused it?

Mar 8, 2017 at 11:59 PM | Registered CommenterRadical Rodent

RR. Look up a definition of work. Wikki's are:

Work (physics), the work done by, or energy transferred by, a force acting through a distance (ie my hand being warmed by photons radiated from the ground)

Work (thermodynamics), the energy transferred from one system to another by macroscopic forces measurable in the surroundings. ( same)
-------
------

Which part of what I have written violates any part of such definitions?

Mar 8, 2017 at 3:10 PM | Unregistered CommenterSupertroll

Supertroll - 'work', by the definition universally accepted (eg wiki), is mechanical force × distance through which the point of application of the force moves while the force is applied.

Work (physics), the work done by, or energy transferred by, a force acting through a distance (ie my hand being warmed by photons radiated from the ground)

Supertroll - I recommend getting somebody to explain it all to you. "Acting through a distance" refers to the the point at which the force is applied moving a distance while the force continues to be applied. Nothing to do with radation being absorbed some distance from where it was emitted.

Talking about photons doing work is your own invention. Better to avoid waffling on about things you don't understand, even though you may think it sounds impressive.

Mar 9, 2017 at 9:22 AM | Unregistered Commenterdulac

Supertroll, I am looking forward to a Climate Science definition of "work", and what they have been doing for the last 20 years, whilst being paid loads of money.

Mar 9, 2017 at 9:33 AM | Unregistered Commentergolf charlie

Radical rodent

Back to your old habits, I see.

Mar 9, 2017 at 9:42 AM | Unregistered CommenterEntropic man

Back to your old habits, I see.
What? Pulling you up when you slip?

No – don’t thank me; I’m always happy to help.

Mar 9, 2017 at 10:01 AM | Registered CommenterRadical Rodent

dulac. Wow! Does this mean that the next time I use my electrical fire I can discount my electrical bill because, in warming me, no work was actually done? What has physics education come to? Your definition is purely mechanical, what about thermodynamic work? Please don't bother to answer, I am no longer interested.

Mar 9, 2017 at 10:50 AM | Unregistered CommenterSupertroll

"Talking about photons doing work is your own invention."

I don't believe it is SS's own invention, see simple equation above. When an electron is hit by a photon it absorbs the energy of the photon and moves to a higher energy orbit (work), it then almost instantly returns to the lower energy orbit and the atom emits the photon. Standard text book explanation.

Mar 9, 2017 at 11:15 AM | Unregistered Commentergeronimo

Climate Scientists have fabricated their own concept of "doing work". Having failed to revise their theories, to cope with their lack of supporting evidence, they may have to adjust their lifestyles, to the imbalance of cash, flowing in and and out of their bank accounts.

Some practical experience of genuine problems, faced in the big wide world, could cause many Climate Scientist to work for free, burning candles at both ends, so they get their theories right. In the real world, away from computer modelled depictions of Climate Science eutpopia, most won't bother, and will sell Life Insurance, Funeral Plans AND double glazing to hedge their bets in the "futures" prediction market.

Mar 9, 2017 at 11:58 AM | Unregistered Commentergolf charlie

Supertroll, geronimo, feel free to redefine the standard terms of physics how you wish.

All the same, 'work' is universally taken as mechanical work ie force times distance. It's not normally used in talking about electron orbits, the output of electric fires, absorption of radiant energy and so on. In thermodynamics, work and heat are different things.

In talking about infra-red doing 'work' in warming his hand, or asking "what about thermodynamic work?" Supertroll is making it clear that he is waffling about stuff he does not really understand. He might take a moment to look at any of the hundreds of clear definitions instantly available:

- - - Work is done when a force that is applied to an object moves that object. The work is calculated by multiplying the force by the amount of movement of an object (W = F * d). A force of 10 newtons, that moves an object 3 meters, does 30 n-m of work. A newton-meter is the same thing as a joule, so the units for work are the same as those for energy – joules.

Mar 9, 2017 at 12:02 PM | Unregistered Commenterdulac

Mar 9, 2017 at 12:02 PM | dulac

How do you explain how Climate Scientists got it so wrong about CO2 causing Global Warming? It seems to be leaving many careers and livelihoods in tatters.

Mar 9, 2017 at 1:22 PM | Unregistered Commentergolf charlie

dulac "feel free to redefine the standard terms of physics how you wish."

I admit to being a bit rusty on the photo-electric effect, but when a photon with the appropriate energy collides with and electron the electron will move, if there is enough energy in the proton (called the WORK function) the electron will be ejected from the atom. If there isn't the electron will move to a different orbit either way the photon transfers energy to the electron and the electron changes state. If it isn't ejected by the force of the photon it will return to its former state and the atom will emit a photon randomly. That's where I'm coming from, if you have more information, or can point to where I'm mistaken I'd appreciate it.

Mar 9, 2017 at 2:01 PM | Unregistered Commentergeronimo

Really dulac? I suggest you change your sources of physics definitions. One of the earliest experiments, I hope conducted in every science schoolroom, was carried out by Joule who showed the equivalence of work and heat (mechanical force converted into heat energy). All forms of energy ultimately are converted to heat when work is done. When my hand is heated by the flux of IR photons, work is being done.
To confine your definition of work only to the mechanical is totally incorrect. Force x distance, includes all types of forces including interacting particle (photon, electron, neutron, etc) fluxes. All these transfers can do work, even mechanical work (piezoelectric effects (crystal deforms when electric current applied), light sails in spacecraft, spinning turbines in the device my grandson and I dreamed up and which Radical Rodent wrote that she had seen). To some effects we even give specific names - Piezoelectric effect, photoelectric effect. Other types of change can result from the application of photons - like the chemical changes that occur on photographic plates, or structural damage to DNA by X or cosmic rays. These changes involve the movement of parts of the chemical compounds involved. Where do your definitions stop considering mechanical movement? Do you consider work is done to moderating rods when their crystal lattices deform under the influence of nuclear radiation? If not, why not?

I seem to have remembered slightly more physics than you now seem to possess and I am losing brain cells by the bucketload.
As I implied earlier, science teaching must be crap since I was taught it.

Mar 9, 2017 at 2:26 PM | Unregistered CommenterSupertroll

As I implied earlier, science teaching must be crap since I was taught it.

Mar 9, 2017 at 2:26 PM | Supertroll

But nobody had invented Climate Science back then, with it's radical thinking, that has so radicalised so many.

Trump may need to discuss with Cuba the possibility of extending Guantanamo Bay, as a Deradicalization Centre for Climate Science.

Mar 9, 2017 at 3:07 PM | Unregistered Commentergolf charlie