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[cem_devecioglu]

ok.. although last night I was sleepless because of neighbours, I didnt bother to open the pc and check oof  :-/ with the hope of sleeping at any chance..

My intention is not to start another slanging match but to share my info and views  which I couldnt post on oof last night..


dont know how many of you has suffered thermodynamics exams or lectures in the past..

I had..



there is a law..

it says that "energy can neither be created nor destroyed.. only it can be

converted from one form to another.." (first law of thermodynamics..) 


now , we all know that earth surface in day time become hotter by sun light (absorbing energy)

so it has to cool down otherwise the temperature will continue to rise and we will all boil up.. :-?

this cooling happens in the form of emitted thermal energy, infrared, that is transmitted to space.. :-?

However , earth, having athmosphere like a blanket  , keeps some of this

energy preventing earth from reaching -273C  in night time (actually it will

never be exact -273.00000000000000000000000 -as 3rd law of thermodynamics also dont let this to happen) ,

saving the life forms from being destroyed..




Now consider a scenario that the earths population increases continously

(is 100 billion enough for you or say 1Kbillion  ) , and so the industrial production , traffic

(air, sea and land ) etc..it will obviously reach to a point that the sum of

energy released from mankind sources wont be negligible compared to energy coming

from the sun..     (although seems to be complex these energy ratios can be calculated

and also measured.. (from thermodynamics avg temperatures will increase in a vessel

without any doubt if you inject more energy -even if its open from one side- regardless of the size)


Now what happens if you change the type of blanket, say from cotton to wool.. 

simple.. average temperatures in specified time slices again will be higher.. :-/



of course, for this heating - cooling periods athmosphere has a cooling rate which can increase with the

higher temperatures (its like a safety valve) ..


Now in theory (forget other factors for a while) (which actually is not the case) at a fix hour (say 6 am in the morning ) the

temperature must go back to the previous state as the previous days morning 6 am but between

those hours the avg temperatures at some specific points will be higher then the previous

if you continue to increase the amount of energy released..


However the real life weather is more complicated than this scenario as oceans, rivers,lakes,

clouds-which reflects the suns radiation,  earths orbital around the sun (winters , summers) etc disturbs

the equation, transports the energy and in a way balances the system earlier than the cooling period..


However I must note that

* all those balancing systems have finite powers..

* whatever balancing systems do, its very obvious that avg temperatures between those


heating cooling periods will be higher than previous in a measurable amount.. ( I dont say normal

as the state of being normal is very relative or undefined)


 

[Nickbat]

Hi Cem,

It's good that you want to talk about the real science and not enter a slanging match!

I don't have the time (due to work) to post much at this juncture, but I would point out that greenhouse gases do not, as I understand it, act together as a conventional blanket since they do not trap convective heat. Also, 70% of the planet is ocean, which is worth bearing in mind when we talk of the effects of urbanisation on the planet as a whole.

I addition to the UHI effect, there are also land use changes which have an effect on local climates, so I do not deny that humanity has no climatic effect at all, just that the overall effect is not potentially catastrophic. I do believe, though, that the fixation on CO2 as the number 1 problem (which i do not believe it is) is diverting attention from real ecological problems such as deforestation.

I think the link below is excellent. It answers many of the questions about the greenhouse effect in layman's terms.

http://www.junkscience.com/Greenhouse/

Now, back to work....        

[Chris_H]

I'm not sure if there was actually a question in there Cem?

Don't forget that conservation of energy theorem requires that you consider the whole system (but you can choose the system boundaries).  So if you are considering the earth as the system, then you have to combine external energy inputs from outside the system (the sun etc.) with the losses out of that system (radiation from the far side, loss of matter, gain of matter (meteorites etc.).

What mankind does is not creating energy, he converts it by burning fossil fuels, converting matter to energy (nuclear fission etc.).  These are entirely within the system defined as the earth so produce no net energy change according to the law.

...possibly 

[Sixstring]

WOW!!  (bit much for my poor brain at this time, but interesting stuff, however and very "deep")

How do "human emissions" and "bovine methane expultion" change this equation??

Seeing as cattle emit staggering amounts of methane gas into the environment I would assume SOMEBODY has factored all this into the argument?

[zirk]

 :-? Think Ive just logged on to the wrong Forum.

[Lizzie_Zoom]

Thanks Cem for that very interesting and thought provoking scientific analysis 8-) 8-) 8-) .

[Sixstring]

PMSL..... :-?

[Chris_H]

Hi Cem,

It's good that you want to talk about the real science and not enter a slanging match!

I don't have the time (due to work) to post much at this juncture, but I would point out that greenhouse gases do not, as I understand it, act together as a conventional blanket since they do not trap convective heat. Also, 70% of the planet is ocean, which is worth bearing in mind when we talk of the effects of urbanisation on the planet as a whole.

I addition to the UHI effect, there are also land use changes which have an effect on local climates, so I do not deny that humanity has no climatic effect at all, just that the overall effect is not potentially catastrophic. I do believe, though, that the fixation on CO2 as the number 1 problem (which i do not believe it is) is diverting attention from real ecological problems such as deforestation.

I think the link below is excellent. It answers many of the questions about the greenhouse effect in layman's terms.

http://www.junkscience.com/Greenhouse/

Now, back to work....        

I'm intrigued that you separate deforestation from the CO₂ debate since a main feature of deforestation is reduced CO₂ absorption and O₂ creation.

[Dishevelled Den]

This is getting to be an intractable problem made more so as the science charged with investigating it has been devalued to a large extent by the by the questionable agenda of so many groups/individuals unconnected to the scientific community.

The eye has effectively been taken off the ball and the very real problems that humanity will face in the near future such as a stable food supply, continued availability of potable water, increasingly unstable political systems, increasing use of capital violence to express will, ever more fragile global financial arrangements and so on will bite hard as time goes on.

Insofar as AGW is concerned my take on this was expressed in that other thread (Part excerpt);


I have no problem with accepting that there are indeed changes happening to the climatic balance we've all experienced and enjoyed over the recent past.  As far as I’m concerned however this is part of the natural cycle driven by a living planet powered by its sun - the only reason incidentally for earth's ability to support life in the first place -   - our impact in terms of atmospheric pollutants which may contribute to an overall heating (if this does indeed exist in any extensive way) is in my view minimal.

Where we have altered things to the detriment of the planet seems to spring from avarice and the lust for power and influence: The stripping of the rain forest for gain, deforestation of vast swaths of land for the purposes of mining/building, the constant probing of the planet in the search for energy sources.

The list is extensive but always seems to depend on the use, and in some cases the over use, of planetary resources.  This in my view is more worrying than the alleged overheating of the global atmosphere by what we’ve done over the last one hundred years or so.

Aside from this, I’m surprised that many apparently sensible people appear to accept, without question, the assertions of individuals/groups who maintain that the science is ‘settled’ in terms of AGW.  Since when is science ever settled?

And, despite CEM’s rather involved piece, I'm still of this view.

[Dishevelled Den]

ok.. although last night I was sleepless because of neighbours, I didnt bother to open the pc and check oof  :-/ with the hope of sleeping at any chance..

My intention is not to start another slanging match but to share my info and views  which I couldnt post on oof last night..


dont know how many of you has suffered thermodynamics exams or lectures in the past................

Thank's for that cem, can you tell me what it means in practical terms as I know nothing about thermodynamics.

[Sixstring]

Yes CEM, "suffered" being the right word. I was a lot younger then, with a much less attention span and although my lecturer was a decent chap, he never really made the subject "interesting".
A lot of it therefore went straight over my head, and through my ears.

[cem_devecioglu]

I'm not sure if there was actually a question in there Cem?

1 Don't forget that conservation of energy theorem requires that you consider the whole system (but you can choose the system boundaries). 

Yes..

2 So if you are considering the earth as the system, then you have to combine external energy inputs from outside the system (the sun etc.) with the losses out of that system (radiation from the far side, loss of matter, gain of matter (meteorites etc.).

main energy sources are considered as you can see above..and the system boundries are above crust and below athmospheric-space boundry -ionosphere etc

3 What mankind does is not creating energy, he converts it by burning fossil fuels, converting matter to energy (nuclear fission etc.). 

Yes..


4 These are entirely within the system defined as the earth so produce no net energy change according to the law.

no.. when you burn fossil fuels you transfer energy from underground to the system where we live..

...possibly 

[Sixstring]

Blimey!! a bit too deep for my limited amount of brain cells to digest, but very interesting all the same. Wish I'd listened more at lectures now..................

[cem_devecioglu]

WOW!!  (bit much for my poor brain at this time, but interesting stuff, however and very "deep")

Thanks

How do "human emissions" and "bovine methane expultion" change this equation??

Seeing as cattle emit staggering amounts of methane gas into the environment I would assume SOMEBODY has factored all this into the argument?

they add energy to the system

[cem_devecioglu]

:-? Think Ive just logged on to the wrong Forum.