Is it possible to have a rational debate on global warming?

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BattleMoose
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Re: Is it possible to have a rational debate on global warmi

Postby BattleMoose » Mon Dec 17, 2012 12:21 pm UTC

Its pretty much all us.
http://www.realclimate.org/images/ipcc2007_radforc.jpg

Well, on the timescales we are talking about.

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Re: Is it possible to have a rational debate on global warmi

Postby Drowsy Turtle » Mon Dec 17, 2012 12:57 pm UTC

BattleMoose wrote:Its pretty much all us.
http://www.realclimate.org/images/ipcc2007_radforc.jpg

Well, on the timescales we are talking about.


Graph is unclear. Is it looking at the radiative forcing due to the change in the various factors, or is it the radiative forcing at current values? How does this correspond to atmospheric and hydrospheric temperature changes compared to, say, geothermal heat?

I have doubts about the efficacy of carbon dioxide as a greenhouse gas, especially since working with climate proxies. Carbon dioxide and temperature both seem to follow the same pattern as orbital forcing on the thousand-to-million year timescale; it suggests to me that carbon dioxide isn't a dominant control on climate - the effects are too small in the short-term, and in the long-term they equilibrate to existing cycles.

Spoiler:
I'm working on a model where orbital cycles are removed, leaving just the longer-term trends and short-term variability, but progress is slow and I won't receive any credit for this so might abandon it.
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Re: Is it possible to have a rational debate on global warmi

Postby BattleMoose » Mon Dec 17, 2012 1:12 pm UTC

Drowsy Turtle wrote:Graph is unclear.


Then read the IPCC reports, if you haven't seen that chart before and are choosing to engage in this discussion then you really do have some reading to do.

Is it looking at the radiative forcing due to the change in the various factors, or is it the radiative forcing at current values?


Its both. And you'll note, its just about entirely anthropogenic.

How does this correspond to atmospheric and hydrospheric temperature changes compared to, say, geothermal heat?


Its got absolutely nothing to do with geothermal heat. That chart is simply the radiative energy balance and it shows that the changes to our radiative energy balance are almost exclusively anthropogenic. If you are going to go in the direction of suggesting the temperature of our atmosphere is changing because of changes in geothermal heat, then that would be a first for me, and I've been doing this for some time.

I have doubts about the efficacy of carbon dioxide as a greenhouse gas, especially since working with climate proxies.


Thats nice? Proxies are useful, but they have nothing to do with calculating our radiative energy balance. They are pretty much only used for reconstructing past climates.

Carbon dioxide and temperature both seem to follow the same pattern as orbital forcing on the thousand-to-million year timescale; it suggests to me that carbon dioxide isn't a dominant control on climate - the effects are too small in the short-term, and in the long-term they equilibrate to existing cycles.


There are reasons for this and you would do better learning about it from a proper source of information than some random on the internet. You might think that the effect of CO2 is too small but I can tell you, that the best minds we have, have calculated its effect to about 1.75w/m2.

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Re: Is it possible to have a rational debate on global warmi

Postby lokar » Mon Dec 17, 2012 1:26 pm UTC

BattleMoose wrote:Its pretty much all us.
http://www.realclimate.org/images/ipcc2007_radforc.jpg

Well, on the timescales we are talking about.


Is the CO2 bar indicating Human (Anthropogenic) CO2 Emission or the whole Human+Natural CO2 Emission?

Lokar

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Re: Is it possible to have a rational debate on global warmi

Postby BattleMoose » Mon Dec 17, 2012 1:30 pm UTC

lokar wrote:
BattleMoose wrote:Its pretty much all us.
http://www.realclimate.org/images/ipcc2007_radforc.jpg

Well, on the timescales we are talking about.


Is the CO2 bar indicating Human (Anthropogenic) CO2 Emission or the whole Human+Natural CO2 Emission?

Lokar


All of it. But its worth noting, that the natural system, is a net sink of CO2, its going into the oceans.

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Re: Is it possible to have a rational debate on global warmi

Postby lokar » Mon Dec 17, 2012 3:19 pm UTC

BattleMoose wrote:
lokar wrote:
BattleMoose wrote:Its pretty much all us.
http://www.realclimate.org/images/ipcc2007_radforc.jpg

Well, on the timescales we are talking about.


Is the CO2 bar indicating Human (Anthropogenic) CO2 Emission or the whole Human+Natural CO2 Emission?

All of it.


Isn't Anthropogenic CO2 to Natural CO2 emission ratio around 4%?
Is it right to read the label "Total net anthropogenic" as "Total net of Radiating Forcing which are (partially) influenced by anthropogenic causes"?
If so, how much is the anthropogenic component of the whole thing? Are we sure it (the human component) is enough alone to drive the whole climate trend? The graph seems not to support your previous sentence:

BattleMoose wrote:Its pretty much all us.


In fact, its purpose seems to show only which components (some of which are human activity related) compose the Radiative Forcing.

Also, aren't the error bars really long? So long, actually, you could balance/reverse the whole direction? I'm sorry, but that chart doesn't seem to settle the whole discussion.

BattleMoose wrote:But it's worth noting, that the natural system, is a net sink of CO2, it's going into the oceans.


Probably due to my not being a native English speaker I find it difficult to parse the above sentence (even after fixing the apostrophes)... especially the last part. Could you please explain?

I may not look as a human-driven-climate-change-theory-supporter but I am actually really very open to both views, so please give me the benefit of the doubt.

Thank you,

Lokar

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Re: Is it possible to have a rational debate on global warmi

Postby The Great Hippo » Mon Dec 17, 2012 3:55 pm UTC

delooper wrote:My point wasn't to give an elaborate essay as that's not how the dynamic in a forum works. But in short, the fundamentals of the climate models are wrong. Even the basic physics they use is usually only a 0th, maybe sometimes a 1st order approximation but much of the basics are fundamentally off. For example, co2 and nitrogen transfer between the oceans and the atmosphere are way off in the models compared to what is measured. Tropical weather systems are way off from the models to what is observed. The models make short terms predictions that are almost always at odds with observations. And so on. I'm not saying anything here that climate scientists don't already know, many admit these things.
Okay, but you understand that for science to work, you don't need your basic physics to be 'on'? For something to be scientific, it must only produce good predictions.

If my achey knee model makes better predictions about the climate than a climatologist's global warming model, my achey knee model is 'more scientific'--despite having no grounding in physics. Because tests reaffirm my achey knee model over the global warming model!

Physics are not the foundation of science. Experiments are the foundation of science. If my model defies physics--but makes better predictions than physics ever could--the problem is not my model.
delooper wrote:That seems kind of not relevant to the discussion.
The quote is a reference to a saying I like: 'There are no camels in the Quran'.

What it essentially means is this: If you do not see what you expect to see, this is not always indicative that what you expect to see is not present. I would expect to see camels in the Quran, because the Quran takes place in the middle-east--but I see no camels in the Quran. What does this mean? Does it mean there were no camels in Arabia at the time of the Quran's writing? Does it mean the Quran itself is not an authentically 'Arabian' document?

Of course not. My failure to see camels in the Quran is my problem, not the Quran's. There are camels in the Quran! They're just not stated explicitly, because camels--in Arabia--were incredibly ordinary. The Quran is full of camels; I don't see them because I'm not really looking for them.

The way this is relevant: Perhaps you don't see science in climate science because you're not looking for science in climate science. Perhaps you're saying "There are no camels in the Quran--therefore the Quran is not actually an Arab work".

It's a possibility that's always worth considering--because it's a trap that's very easy to fall into.

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Re: Is it possible to have a rational debate on global warmi

Postby Zamfir » Mon Dec 17, 2012 4:37 pm UTC

lokar wrote:
BattleMoose wrote:
lokar wrote:
BattleMoose wrote:Its pretty much all us.
http://www.realclimate.org/images/ipcc2007_radforc.jpg

Well, on the timescales we are talking about.


Is the CO2 bar indicating Human (Anthropogenic) CO2 Emission or the whole Human+Natural CO2 Emission?

All of it.


Isn't Anthropogenic CO2 to Natural CO2 emission ratio around 4%?
Is it right to read the label "Total net anthropogenic" as "Total net of Radiating Forcing which are (partially) influenced by anthropogenic causes"?
If so, how much is the anthropogenic component of the whole thing? Are we sure it (the human component) is enough alone to drive the whole climate trend? The graph seems not to support your previous sentence:

The key here are isotopes. Different carbon sources and sinks release/absorb carbon with different isotope compositions (in particular, all C14 in fossil fuel has decayed). So by studying the changes in isotopic composition of carbon in the atmosphere, it is possible to conclude which sources are driving the change in CO2 concentration.

If I remember correctly, fossil fuels are responsible for most of the change, with deforestation doing a minor but significant rest part. Other effects are a net sink at the moment, as BattleMoose mentioned. The oceans for example seem respond to the higher concentration by absorbing more than they release.

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Re: Is it possible to have a rational debate on global warmi

Postby morriswalters » Mon Dec 17, 2012 4:51 pm UTC

Separate the two debates, and there are two. The scientific debate is fraught with uncertainty, it could be wrong in its facts or its assumptions or its mechanisms. I'm quite certain that debate will rage for centuries until they are handed a fait accompli . Then there is the public policy debate. This is not a scientific debate. The question becomes not if Global warming is happening and why, rather one of, if it is what should we do and what can we afford not to do. Unless your eyes see something mine don't, carbon abatement is not going to happen in the short term. So the point of what are we going to do about CO2 deferred by debate, in other words we're talking it to death. On the other hand extreme weather events call into question things we can do in the short term and which have value even if human caused climate change is a myth. If the earth is warming, what that may mean is that the climate system could become unstable and chaotic. Warming would also infer that the sea level would rise. The points to two obvious things, if current areas used for food production shift, the current bounty we enjoy may go away. If you wait for certainty you could end up with famine. If the sea level rises the rather large percentage of the world population that will be impacted may have to migrate away from the shore. Given that most land is now occupied that presents a major problem. And the problem will be greatest among those least able to deal with it. Which is why major Military and Security apparatuses are planning around the question.

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Re: Is it possible to have a rational debate on global warmi

Postby Drowsy Turtle » Mon Dec 17, 2012 5:06 pm UTC

BattleMoose wrote:
I have doubts about the efficacy of carbon dioxide as a greenhouse gas, especially since working with climate proxies.


Thats nice? Proxies are useful, but they have nothing to do with calculating our radiative energy balance. They are pretty much only used for reconstructing past climates.


It's extremely relevant. If the effect of carbon dioxide as a greenhouse gas is less than predicted, then the radiative energy balance is smaller than calculated.

BattleMoose wrote:
Carbon dioxide and temperature both seem to follow the same pattern as orbital forcing on the thousand-to-million year timescale; it suggests to me that carbon dioxide isn't a dominant control on climate - the effects are too small in the short-term, and in the long-term they equilibrate to existing cycles.


There are reasons for this and you would do better learning about it from a proper source of information than some random on the internet. You might think that the effect of CO2 is too small but I can tell you, that the best minds we have, have calculated its effect to about 1.75w/m2.


I'm aware of at least some of the mechanisms, although what they are doesn't really matter for my point - that CO2 doesn't seem to have particularly much effect on climate in the long-term. On a human time scale the warming is significant because we're artificially accelerating CO2 release into the atmosphere, but over a couple of hundred years or so the system will return to equilibrium (maybe slightly warmer than before the industrial revolution).

Bearing this in mind, and with hydrocarbon reserves being what they are, doomsday predictions seem a little far-fetched, and a runaway hothouse event sounds impossible (I'm not saying you necessarily believe this, just stating my position).
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Re: Is it possible to have a rational debate on global warmi

Postby addams » Mon Dec 17, 2012 6:25 pm UTC

Doomsday?
Every day is Doomsday.

A good long term public policy is a pleasure all by its self.
I don't really understand it. I listened to a lecture about buildings that will make lovely ruins. That is long term thinking.

The target audience were architects.
The time was post war, Europe.
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Re: Is it possible to have a rational debate on global warmi

Postby Nylonathatep » Mon Dec 17, 2012 11:45 pm UTC

Global Warming is a bunch of people telling you that it's your fault and you'll have to pay them lots of money to make it go away.

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Re: Is it possible to have a rational debate on global warmi

Postby delooper » Mon Dec 17, 2012 11:54 pm UTC

The Great Hippo wrote:
delooper wrote:My point wasn't to give an elaborate essay as that's not how the dynamic in a forum works. But in short, the fundamentals of the climate models are wrong. Even the basic physics they use is usually only a 0th, maybe sometimes a 1st order approximation but much of the basics are fundamentally off. For example, co2 and nitrogen transfer between the oceans and the atmosphere are way off in the models compared to what is measured. Tropical weather systems are way off from the models to what is observed. The models make short terms predictions that are almost always at odds with observations. And so on. I'm not saying anything here that climate scientists don't already know, many admit these things.
Okay, but you understand that for science to work, you don't need your basic physics to be 'on'? For something to be scientific, it must only produce good predictions.


Sure, but the point is that we're forming a model. And the model fails to predict accurately. Not only does it fail to predict on small time scales (experimentally) but we see sound *reasons* for why it fails to predict. The quantity of CO2 transferring between the atmosphere to the ocean is likely a big deal in the study of climate change, and that's far from nailed down. And this isn't even addressing issues of the mathematical robustness of the models given the massive error bars going into the base assumptions of the models. And this isn't addressing fundamental physical correctness of the model. I'm talking about plain and simple "model -> prediction -> experiment -> not the same". Basic science.

The way this is relevant: Perhaps you don't see science in climate science because you're not looking for science in climate science. Perhaps you're saying "There are no camels in the Quran--therefore the Quran is not actually an Arab work".

It's a possibility that's always worth considering--because it's a trap that's very easy to fall into.


That's an interesting hypothetical you're putting forward but I don't see where it connects to reality here.

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Re: Is it possible to have a rational debate on global warmi

Postby BattleMoose » Tue Dec 18, 2012 12:10 am UTC

lokar wrote:Isn't Anthropogenic CO2 to Natural CO2 emission ratio around 4%?


No. I have no idea where you pulled this number from but its simply not true.

Is it right to read the label "Total net anthropogenic" as "Total net of Radiating Forcing which are (partially) influenced by anthropogenic causes"?
If so, how much is the anthropogenic component of the whole thing? Are we sure it (the human component) is enough alone to drive the whole climate trend? The graph seems not to support your previous sentence:


The title of the graph is fine. Its important to grasp that all the effects listed in the graph are anthropogenic, except the sun.

BattleMoose wrote:Its pretty much all us.


In fact, its purpose seems to show only which components (some of which are human activity related) compose the Radiative Forcing.


Yes I am sure they are deliberately excluding volcanoes and unicorn farts so they can keep their grants.

Also, aren't the error bars really long? So long, actually, you could balance/reverse the whole direction? I'm sorry, but that chart doesn't seem to settle the whole discussion.


Not for CO2 they aren't, which prompted the graph.

BattleMoose wrote:But it's worth noting, that the natural system, is a net sink of CO2, it's going into the oceans.


Probably due to my not being a native English speaker I find it difficult to parse the above sentence (even after fixing the apostrophes)... especially the last part. Could you please explain?

I may not look as a human-driven-climate-change-theory-supporter but I am actually really very open to both views, so please give me the benefit of the doubt.


Huge quantities of the CO2 we are releasing are going into the Oceans.

It's extremely relevant. If the effect of carbon dioxide as a greenhouse gas is less than predicted, then the radiative energy balance is smaller than calculated.


Proxies are not used to calculate the effect of CO2 on warming.

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Re: Is it possible to have a rational debate on global warmi

Postby addams » Tue Dec 18, 2012 1:04 am UTC

I'm feeling moody.
Basic Science.
Start with an oxidation/reduction reaction.

I love that story. Do you remember it?

The Title is:
Why doesn't water burn?

Please, Tell it, again!

water does not burn because it is already burnt.
We all know that. Right?
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Re: Is it possible to have a rational debate on global warmi

Postby The Great Hippo » Tue Dec 18, 2012 1:56 am UTC

delooper wrote:Sure, but the point is that we're forming a model. And the model fails to predict accurately.
If that's the case, then that's the only thing that matters, and that should be the only thing that's talked about.

Everything else is irrelevant. Science demands only one thing: Test your model against reality.
delooper wrote:Not only does it fail to predict on small time scales (experimentally) but we see sound *reasons* for why it fails to predict. The quantity of CO2 transferring between the atmosphere to the ocean is likely a big deal in the study of climate change, and that's far from nailed down. And this isn't even addressing issues of the mathematical robustness of the models given the massive error bars going into the base assumptions of the models. And this isn't addressing fundamental physical correctness of the model. I'm talking about plain and simple "model -> prediction -> experiment -> not the same". Basic science.
'Why' it fails to predict is talking about the fundamental physical correctness of the model. The only reason I'm interested in a 'why' is if the reasons behind the 'why' lead to better models that produce better predictions. If they don't, I don't care--the only relevant piece of data is whether or not a model exists that produces better predictions.

If there is, we should use that model. If there isn't, this model represents the best model we have.

There's nothing else to it.

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Re: Is it possible to have a rational debate on global warmi

Postby BattleMoose » Tue Dec 18, 2012 2:16 am UTC

delooper wrote:Sure, but the point is that we're forming a model. And the model fails to predict accurately.


Which predictions? And what tolerance are you applying to consider calling such a model, accurate?

That being said, our models are able to reproduce the past 100 years, global surface temperature anomaly, pretty damn well.
http://www.ipcc.ch/pdf/assessment-repor ... apter8.pdf (pg 600)

Theres a lot they cannot do, but global temperature anomaly is something they are getting right.

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Re: Is it possible to have a rational debate on global warmi

Postby addams » Tue Dec 18, 2012 6:05 am UTC

What if?
What if we understood where all the water in the oceans came from?
The water and the Carbon came from the same place.

I think we can know this.
We can be reasonable while we consider how simple it is.

It is simply a change in way the world is thought of.

Consider; We are getting more water.
The water is coming from The Core.
Consider it.

Little Kids might buy it. Why can't you?
It is an idea that may change the math, a bit.
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Re: Is it possible to have a rational debate on global warmi

Postby lokar » Tue Dec 18, 2012 2:33 pm UTC

BattleMoose wrote:[...]


Is it possible to have a rational debate on global warming?

Listen, I'm just here to politely ask some questions out of curiosity. You've been rude and dismissive for no particular reason.
I can cope with the rudeness - even if you don't come out well, but hey, this is the internet - but I can't accept a dismissive answer: what's the point of the whole thread, otherwise? If you don't know how to answer or if you feel impatient for some reason, just ignore my posts, please.

BattleMoose wrote:
lokar wrote:Is the CO2 bar indicating Human (Anthropogenic) CO2 Emission or the whole Human+Natural CO2 Emission?

All of it.
Lokar wrote:Is it right to read the label "Total net anthropogenic" as "Total net of Radiating Forcing which are (partially) influenced by anthropogenic causes"?.

The title of the graph is fine. Its important to grasp that all the effects listed in the graph are anthropogenic, except the sun.


Emphasis added. You misled me there, and then you pointed out that I had erroneously interpreted the chart.

BattleMoose wrote:
lokar wrote:In fact, its purpose seems to show only which components (some of which are human activity related) compose the Radiative Forcing.

Yes I am sure they are deliberately excluding volcanoes and unicorn farts so they can keep their grants.


Again. You misled me there. I asked what was the correct way of reading the chart. You said that the CO2 emission bar contemplated ALL of the natural+human emission. Therefore I assumed that the human part was just a bit of it and then expressed some doubts which could involve a simple explanations of how much, hows and whys as a feedback.
However, you abruptly stated it was right (as if I should not be entitled to ask/extrapolate), and that I should concern instead on the effects listed in the graph itself.

If my understanding is correct, and until contradicted, I'll assume the anthropogenic CO2 bar in the graph (such as any other bar under the anthropogenic section) contains the whole human+natural emission/absorption (difference between 2007 and pre-1750) and the human component is just part of it and the the misunderstanding lies in the word "anthropogenic" which - in the context of the graph - seems to mean "human influenced", more than "only human related". If, instead, the bars are intended to show the radiative forcing caused by the human-emission alone, I'd be fine with it, all I was asking for was some clarification, and I based my following questions on the given answer. If not, my questions still stand there, unanswered.

Just for the sake of it, I'll just state what is my opinion on the matter right now.
Anyone, feel free to correct me if I'm wrong on something, I'm just trying to build up some basic knowledge.

I see and accept the following as facts:
- A global warming process (increase of the global mean temperature) is slowly happening (small fraction of 1 C° per century) over time since... ever
- There is a natural phenomenon called greenhouse effect which partially contribute to the global warming process (still can't figure to what extent, though)
- CO2 is a greenhouse gas which partially contribute to the greenhouse effect by an estimated 9% to 26%
- CO2 human emission has increased CO2 concentration by ~30% in the last 260 years or so and that the actual concentration value has far exceeded the latest (400000 years) peak values (even if the earlier peaks where significantly higher).
- Historically, higher CO2 values where coincident with higher temperatures (or vice versa?). Nevertheless, the correlation isn't linear (in fact, very high CO2 concentration values did not mean very high temperatures) and CO2 high concentration did not prevent temperatures to drop again.
- Human CO2 emissions consists of ~4% of whole CO2 emissions[1][2] since you asked; less recent/significant sources settle around that ratio, too..
- Because the net balance of the natural-only carbon emission-absorption would be even (if not slightly negative) (absorption>=emission), by now the whole (human+natural) net balance is changed/reversed by the tiny human-made part.

Genuine question about the latest: what are the odds that a "natural" (not human related) imbalance in CO2 cycle happens (emitted>absorbed)? It happened in the past, does anybody know how and where it came from?

I see and question the following things as "not so well established theories". Again, I'm open to explanations and remarks that could move the following to the above list or to the "probably true" list.
- Significant part of the global warming process is imputable to CO2 emission
- Human CO2 emissions act as a positive feedback mechanism on global warming
- The amount of human CO2 emissions we could ever produce will significantly affect the global warming process
- The amount of human CO2 emissions we could reduce will significantly affect the global warming process
- The amount of human CO2 emissions affects global warming process rate, making it dangerous on human time-scale
- There aren't other more significant, more dangerous and nearer (in time) natural mechanisms and events (non CO2-emission related) we should concern more about and which would require better placed attention and investments.

BattleMoose wrote:
lokar wrote:Also, aren't the error bars really long? So long, actually, you could balance/reverse the whole direction? I'm sorry, but that chart doesn't seem to settle the whole discussion.

Not for CO2 they aren't, which prompted the graph.


Still, the net balance value seems quite broad to draw indisputable conclusions. Geological history suggests there could be a sort of "climate resilience" at levels way much higher than the ones we could ever approach, and the low knowledge of the surface albedo and aerosol mechanisms might underestimate Earth system ability to overcome the human-related greenhouse gases perturbation. I'm not suggesting an animistic way of looking at it, I'm just comparing past non-human-related events with present events and can't see explanations of why everything should go the "drastic way" other than political ones.
Lastly, and again, I am asking without any prejudice, and I'm just willing to learn.

Zamfir wrote:
lokar wrote:Isn't Anthropogenic CO2 to Natural CO2 emission ratio around 4%?
Is it right to read the label "Total net anthropogenic" as "Total net of Radiating Forcing which are (partially) influenced by anthropogenic causes"?
If so, how much is the anthropogenic component of the whole thing? Are we sure it (the human component) is enough alone to drive the whole climate trend?

The key here are isotopes. Different carbon sources and sinks release/absorb carbon with different isotope compositions (in particular, all C14 in fossil fuel has decayed). So by studying the changes in isotopic composition of carbon in the atmosphere, it is possible to conclude which sources are driving the change in CO2 concentration.


Thank you for the clarifications, very interesting indeed. This explains how it is measured, though, not how much is the human/anthropogenic component.

Sorry for the long post. I have a lot of questions and I really would like to learn more, fairly guided by those who know more.

Lokar

P.S. Also, sorry if I messed up with English. If you see any mistake, you would do me a big favor pointing it out (via PM).

[1] Circa 4.2% according to Carbon Cycling and Climate from energy.gov
[2] Circa 3.2% according to Humans and the Global Carbon Cycle from nasa.gov

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Re: Is it possible to have a rational debate on global warmi

Postby delooper » Tue Dec 18, 2012 7:57 pm UTC

The Great Hippo wrote:If there is, we should use that model. If there isn't, this model represents the best model we have.

There's nothing else to it.


There is a bit more. When you make a model, it makes a prediction. Now insert your error bars into your model (the error in the actual model's set-up compared to how reality works, error in experimentally determined parameters, etc) then you ask, "how far away from our initial one can other predictions be if we stick to within those epsilon constraints". Being a climate model, invariably the answer is "enormous amounts". So the models tend not to have much predictive power.

I'm being a little harsh here but my main concern is that the public debate of climate science tends to be filtered through too many official layers of bureaucracy. It's a lot like the cartoon about university websites. They tend to be useless for everyone since they've been filtered through upper-management's perspective of how to attract students -- which has nothing to do with how one attracts students.

Climate science news tends to be highly filtered in that regard. I think that's changing, and it will have to change before people take climate science more seriously, but it will take a while before we see in-depth climate science discussion away from nerdboards like this. :mrgreen: Moreover, regardless of how robust the science is, the general public isn't going to take initiative on things like IPCC and AAAS pronouncements -- that comes across as being too akin to fatwahs and papal infallibility. They're going to want to feel like things have been publicly vetted. In that regard I think climate science is too in-the-closet for the role it wants to have in public policy.

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Re: Is it possible to have a rational debate on global warmi

Postby BattleMoose » Tue Dec 18, 2012 11:25 pm UTC

@lokar

First up, I'm sorry for being snippy. If you had read the whole thread you may understand how it is that I have become so. Not that that excuses my rudeness.

@On Co2 in the atmosphere.

Over the past 100+ years or so, we have released a lot of CO2 into the atmosphere. But the Earth System being as it is has reabsorbed a lot of it into the oceans and the land. Such as it is, the amount of CO2 increase in the atmosphere is a lot less than what we have emitted.

You seem to want to know how much of the extra CO2 was released by humans or the natural system. But this doesn't seem to be a useful question considering the system or one that can be obviously answered. There is an exchange of 210 Gtc/year between the atmosphere and the land and ocean while the net anthropgenic increase is only 9Gtc/y the fundamental difference is that our input is a change to the current equilibrium, a disruption. And the carbon we release is all mixed up with the current exchanges. Although we are fortunate that the land and sea are absorbing so much of our output, for now.

So the chart that was mentioned does include carbon releases from both anthropogenic and the natural system but it happens that the net increase in carbon is almost exclusively anthropgenic.

@On representing anthropgenic emissions as 4% of all emissions
Yes, its technically true. But when presented as such, its usually always been in a deliberately disengenous manner. Usually directly and erroneously concluding that if anthropgenic emissions is only 4% of all emissiosn, then clearly our influence is marginal compared to the natural system and its not us.

It would be much better to present anthropgenic emissions as 225% of the net increase of CO2.

Its the increase of the CO2 in the atmosphere thats of primary relevance.

- A global warming process (increase of the global mean temperature) is slowly happening (small fraction of 1 C° per century) over time since... ever


Firstly there are plenty of times in our past history (millions of years ago) where the global mean temperature has decreased. Secondly, an increase of a small fraction of 1 C° per century is well below IPCC projections.

- There is a natural phenomenon called greenhouse effect which partially contribute to the global warming process (still can't figure to what extent, though)


Our current warming is completely explained by increases of greenhouse gasses, so in short, all of it.

- Historically, higher CO2 values where coincident with higher temperatures (or vice versa?). Nevertheless, the correlation isn't linear (in fact, very high CO2 concentration values did not mean very high temperatures) and CO2 high concentration did not prevent temperatures to drop again.


In our current warming, increases of CO2 are the cause of our warming.

In the past, CO2 increases was actually part of a positive feedback loop, associated with a warming from changes in our orbit, Milankovitch cycles, operating on very long timescales. When our orbit allowed for more heat to be absorbed from the sun, being closer, our planet would warm, which would allow for the oceans to release CO2 as a postive feedback response. Which is why in the past, not only CO2 and temperature are so well correlated, but CO2 increases actually lag temperature increases.

Genuine question about the latest: what are the odds that a "natural" (not human related) imbalance in CO2 cycle happens (emitted>absorbed)? It happened in the past, does anybody know how and where it came from?


We have disrupted the system so badly, that it would be hard to suggest any changes in our CO2 cycle could be natural as oppose to anthropogenic. If warming continues, it is certainly possible that the oceans become a net source of CO2 (emission>absorption) or the permafrost melts and releases methane, or methane calthrates in the oceans warm and release methane. Such events would just need a warming to occur, and depending on wether that warming was anthropgenic or natural one could argue that the effects of such would either be anthropgenic or natural.

But as I have already eluded to, we have influenced our Earth System so much, that any sudden change in emissions from the natural system would have its cause associated with anthropgenic actions.

Significant part of the global warming process is imputable to CO2 emission


We've even managed to put a number to it, +-1,75w/m2. Thats, very well established.

Human CO2 emissions act as a positive feedback mechanism on global warming


No. A positive feedback mechanism, is a mechanism which enhances a change.

An example is the ice albedo feedback mechanism.
The oceans get warmer.
Warming causes sea ice to melt.
Ocean is much more absorptive than ice so more radiation is absorbed than before.
Therefore we get more warming from the ice melting in addition to the initial warming.

Anyways thats enough from me in one post.

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Re: Is it possible to have a rational debate on global warmi

Postby addams » Thu Dec 20, 2012 6:16 am UTC

I think you may be wrong.

The natural carbon may not have much or anything to do with human actions.
This Planet is a big system.

I am not arguing against public planning that reduces human waste. We can work together to prevent poison from pouring onto the land in rain.
We can and should plan for changes to our coast lines.

I also think this thread is lacking a great deal of fun that is here.

Not only is the Earth not flat it is also not unform. Not uniform, yet interconnected.

The core, the atmosphere and the crust each have a place in the Scence of both weather and cclimate.
Yes. Old Sol is very important, too.
Ole Sol is fairly steady.

Our planet is very dynamic. It may be the end of life as we know it. I
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Re: Is it possible to have a rational debate on global warmi

Postby addams » Thu Dec 20, 2012 6:28 am UTC

I ran out of room.

The changes in our climate could be a call to make life as joyful and grand for 'the people's as possible.

One step is for our Good Will to extend beyond politics bounties. The weather is not contained by political countries.

Now; How can you not consider the core? I was not allowed to ignore the core. Why are you allowed to ignore it?
Hey! Remember when the Russians set the atmosphere on fire? Humans have a huge impact. We are a busy species.
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Re: Is it possible to have a rational debate on global warmi

Postby Nylonathatep » Wed Jan 09, 2013 5:32 pm UTC

To get back to the origional question, Global Warming, in it's core, it just a scientific hypothesis that tries to explain the coorlation between human activity and the Global rise in temperature.

Scientific method demands that data has to be collected, observed, and arrive at a logical conclusion to either disprove or adknowledge the hypothesis.

Disregarding the possibility of false data being presented, The Earth's weather pattern is actually a very complex system that depend on many facts, both internal and external (i.e. The sun, CO2 absorbed by Ocean, etc.)

Because we are constantly collecting and interpreting Data, new theories will always rise to either alter or disprove previous theories.

For example:

http://news.nationalpost.com/2013/01/08 ... r-service/

Over the next five years, “global average temperature is expected to remain between 0.28 degrees celsius and 0.59 degrees celsius above the long-term (1971-2000) average … with values most likely to be about 0.43 degrees celsius higher than average,” reads the new Met Office report. A previous prediction said they would be 0.54 degrees higher.

Likewise, the Met Office’s earlier prediction that “about half” of the years 2010 to 2019 will be warmer than 1998 (which was the warmest year since records were kept, at 0.40 degrees above average) is now unlikely under the new model.


I'll say in the long run, we can have a rational debate on global warming since we can observe the changes in the climet. For example, in the 90's Ozone Layer and Green house effects was the 'big' talk and forms the foundation for the Global Warming argument. You rarely see people bought up these arguments because, as futher study concludes, the role of Ozone Layer and the actual Green house effect is more understood by educated minds. People no long believe that a depleting Ozone Layer would leak air into outer space... for example.

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Re: Is it possible to have a rational debate on global warmi

Postby addams » Thu Jan 10, 2013 4:22 am UTC

Did you think the atmosphere was 'leaking' out through the hole in the Ozone?
That is understandable.
To the best of my knowledge there is an Ozone Layer.
The reported problem is not as much a problem, today.

The Ozone is healing. It looks like healing.
The massive amounts of Ozone are human generated.
I know! It is so weird. Humans may have worked together to save the atmosphere. But, the Ozone was a byproduct of people being people.
Can we effect large systems? YES!


Will the weather on our little rock be Venus like by 2050?
Maybe.
Have you made lunch plans?
Nations must make long term plans. It shows good faith.

There are living humans that still dream of the whole family of man living as one happy family.
A happy family in a boat that will sink, someday.
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Re: Is it possible to have a rational debate on global warmi

Postby Shivahn » Thu Jan 10, 2013 4:52 am UTC

addams wrote:The Ozone is healing. It looks like healing.
The massive amounts of Ozone are human generated.
I know! It is so weird. Humans may have worked together to save the atmosphere. But, the Ozone was a byproduct of people being people.
Can we effect large systems? YES!

While we did manage to save the atmosphere, it was mostly due to us not releasing stuff that kills ozone anymore. I'm pretty sure the ozone we actually produce is destroyed before it manages to get into the ozone layer.

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Re: Is it possible to have a rational debate on global warmi

Postby BattleMoose » Thu Jan 10, 2013 5:23 am UTC

Erh, just on ozone.

It is a very powerful oxidising agent and very short lived, half hour or so. And also well poisonous or toxic, or whichever the right word is.

Its created in the part of the atmosphere we call the ozone layer, through photolytic reactions with O2 absoring light and first splitting and then forming O3 which then decomposes to ordinary O2 again. CFC's and HCFC's, which we have released an abundance of, have made it that far up into our atmosphere and reacts preferentially with ozone, so that it is shorter lived than it would otherwise. Long story short, the equilibrium amount of ozone (Constantly being formed and destructed) in the ozone layer is less because of the cocentrations of CFCs and HCFCs.

Tropospheric ozone, ozone existing in that part of the atmospehre in which we occupy, is formed through photocatalytic reactions involving NOx, which is emitted from our cars, which is a very real human health issue, you do not want to be breating in ozone. And this ozone will not survive long enough to get anywhere near the ozone layer.

EDIT:
We have generally been very succesful in reducing our emsissions of CFCs and HCFCs, see Montreal Protocol.

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Re: Is it possible to have a rational debate on global warmi

Postby Shivahn » Thu Jan 10, 2013 6:40 am UTC

Holy shit that NFPA triangle is not what I expected.

That is not a friendly molecule.

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Re: Is it possible to have a rational debate on global warmi

Postby addams » Tue Jan 15, 2013 6:35 am UTC

Shivahn wrote:Holy shit that NFPA triangle is not what I expected.

That is not a friendly molecule.

Link, please.
I like unfriendly molecules.
On a screen.
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Re: Is it possible to have a rational debate on global warmi

Postby Shivahn » Tue Jan 15, 2013 7:40 am UTC

Here is your link.

I tried to copy the NFPA for you but it looks like it's not an image; it's constructed using a table of some kind.

The important information: 0 fire, 4 reactivity, 4 health hazard, oxidizer.

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Re: Is it possible to have a rational debate on global warmi

Postby Max™ » Sun Jan 20, 2013 4:52 am UTC

I gotta apologize, once the conversation turned towards a discussion of consensus and I started taking part in it, I got disgusted with myself and logged out. I told myself I wouldn't fall back into wasting time going over the merits of it again, and when I realized I had, I just threw my hands up in the air and said fuck it. Haven't been back in a while, actually only did because when I had to update some passwords for school (they have to be changed every so often) I took the opportunity to clean up my email accounts and set up the POP account for my gmail and school, which wound up with a bunch of the private message notifications popping up as unread, so I logged in to check and realized it had just sent the old ones again. Wandered over here, looked through some, but didn't feel like getting back in to the discussion at the time.

Just recently though I was reading up on some thermodynamic references as I needed some citations to include for a paper and I'm curious about something.


When you look at things like the Trenberth energy budgets they have the IR as 396 W/m2 up and 333 W/m2 down, right?

In the pdf for the 2009 budget I notice the radiative emission is given as: P = εσA(T⁴) for a surface at 289 K* with unity emissivity, hence 396 W/m2, which seems fine at first.

I thought that equation was only for emissions into an ambient environment which is much cooler than the hot surface.

For the situation like the surface and atmosphere, the temperatures are far too close to use that approximation, it should be P = εσA(Th⁴ – Tc⁴) shouldn't it?



That raises a new question though... thermal emission and absorption of infrared involves molecular vibration modes.

Temperature is a measurement of the kinetic energy in a substance, translational+rotational+vibrational modes all together.

A solid doesn't really have much translational or rotational freedom for the molecules, so the temperature of a solid is essentially a measurement of the vibrational kinetic energy of the molecules.

That same fund of vibrational energy is also responsible for conductive losses to gases and fluids in contact with the surface, isn't it? So how could a surface at 289 K emit 396 W/m2 AND undergo conductive/convective/evaporative losses adding up to 97 W/m2 (Trenberth et al, 2009)? Setting aside that the 396 W/m2 value itself is only valid if the ambient temperature is far lower than that of the surface. Is there some sort of "extra" vibrational energy which doesn't count for temperature measurements and only shows up in non-radiative transfers?


*The temperature they give is 15 Celsius, though 396 W/m2 corresponds to 289 K which is 15.85 Celsius, and they do note that emissivity isn't actually unity, by the way.
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Re: Is it possible to have a rational debate on global warmi

Postby Bad Hair Man » Sun Jan 20, 2013 11:02 pm UTC

Max™ wrote:When you look at things like the Trenberth energy budgets they have the IR as 396 W/m2 up and 333 W/m2 down, right?

In the pdf for the 2009 budget I notice the radiative emission is given as: P = εσA(T⁴) for a surface at 289 K* with unity emissivity, hence 396 W/m2, which seems fine at first.

I thought that equation was only for emissions into an ambient environment which is much cooler than the hot surface.


When atoms radiate photons in accordance with the Stefan–Boltzmann law, they do so independently of the state or temperature of whatever substance those photons end up bumping into or interacting with at a later time. In other words, the equation holds for emissions into (or at) any environment.

Max™ wrote:For the situation like the surface and atmosphere, the temperatures are far too close to use that approximation, it should be P = εσA(Th⁴ – Tc⁴) shouldn't it?


That equation will calculate the net radiative energy transfer between two substances at different temperatures maybe. Actually, I'm not sure if perhaps additional factors would need to be added to that equation to take into account potentially different emissivity, reflectivity, and transitivity profiles of the substances in question. (Notice on the Trenberth energy budget, for instance, that 40 W/m2 is radiated from the Earth, passes completely through the atmosphere and out into space. That looks like partial atmospheric transitivity to me.)

In any case, I think netting the 356 W/m2 radiated from the surface to the atmosphere with the 333 W/m2 radiated from the atmosphere to the surface, to get a net radiative heat transfer of 23 W/m2 from the surface to the atmosphere can be a valid way of presenting what is going on, as long as you are clear on what you are doing and why. i.e. Don't forget that the surface is also absorbing 161 W/m2 from the sun, is radiating 40 W/m2 through the atmosphere into space, is transferring 97 W/m2 to the atmosphere via conduction and evapo-transpiration, and is apparently retaining a net 0.9 W/m2.


Max™ wrote:That same fund of vibrational energy is also responsible for conductive losses to gases and fluids in contact with the surface, isn't it? So how could a surface at 289 K emit 396 W/m2 AND undergo conductive/convective/evaporative losses adding up to 97 W/m2 (Trenberth et al, 2009)?


I think you're confusing in your model a "fund" of energy with a "fund" of power. It's possible for a box full of jellybeans to lose those jellybeans both by people taking beans off the top every once in a while, AND by beans draining out a hole in the bottom of the box. Both of these methods of loss will tax the "fund" of total beans in the box, but whether or not the jellybeans in the box are at an equilibrium condition will depend on how the total losses compare to whatever source (or fund) continues to replenish the beans over time.

A surface at 289 K emits 396 W/m2 of radiation because that's what black-bodies at 289 K do. It's independent of just how fast or how cold or how conductive a wind blowing across that surface may be. The Stefan–Boltzmann law describes how much energy a body emits via radiation based on its temperature. It is independent of (it is neither constrained by, nor puts any bounds on) other ways that that body may have energy transferred either into or out of itself.
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Re: Is it possible to have a rational debate on global warmi

Postby Max™ » Mon Jan 21, 2013 4:28 am UTC

Bad Hair Man wrote:
Max™ wrote:When you look at things like the Trenberth energy budgets they have the IR as 396 W/m2 up and 333 W/m2 down, right?

In the pdf for the 2009 budget I notice the radiative emission is given as: P = εσA(T⁴) for a surface at 289 K* with unity emissivity, hence 396 W/m2, which seems fine at first.

I thought that equation was only for emissions into an ambient environment which is much cooler than the hot surface.


When atoms radiate photons in accordance with the Stefan–Boltzmann law, they do so independently of the state or temperature of whatever substance those photons end up bumping into or interacting with at a later time. In other words, the equation holds for emissions into (or at) any environment.


http://hyperphysics.phy-astr.gsu.edu/hb ... an.html#c1

R. Nave wrote:For hot objects other than ideal radiators, the law is expressed in the form:
Image
where e is the emissivity of the object (e = 1 for ideal radiator). If the hot object is radiating energy to its cooler surroundings at temperature Tc, the net radiation loss rate takes the form:
Image
The Stefan-Boltzmann relationship is also related to the energy density in the radiation in a given volume of space.


Max™ wrote:For the situation like the surface and atmosphere, the temperatures are far too close to use that approximation, it should be P = εσA(Th⁴ – Tc⁴) shouldn't it?


That equation will calculate the net radiative energy transfer between two substances at different temperatures maybe. Actually, I'm not sure if perhaps additional factors would need to be added to that equation to take into account potentially different emissivity, reflectivity, and transitivity profiles of the substances in question. (Notice on the Trenberth energy budget, for instance, that 40 W/m2 is radiated from the Earth, passes completely through the atmosphere and out into space. That looks like partial atmospheric transitivity to me.)

The hyperphysics site goes over the same thing as the textbooks I checked here, http://hyperphysics.phy-astr.gsu.edu/hb ... me.html#c1

R. Nave wrote:The rate of radiative energy emission from a hot surface is given by the Stefan-Boltzmann law .

Image

Here P is the power emitted from the area, and E is the energy contained by the object. For very hot objects, the role of the ambient temperature can be neglected. If the hot temperature is more than 3.16 times the ambient, then the contribution of ambient terms is less than 1%. For example, for 300K ambient on the earth, an object of temperature higher than 1000K can be treated like a pure radiator into space. If the heat loss is purely radiative and not limited by heat transfer to the radiating surface, then the cooling time can be modeled for a hot object.


It also says on the calculator notes:
*The effect of the ambient temperature is neglected. This may be justified. If the hot temperature is more than about three times the ambient, then the error from this assumption is down to 1%
*Other heat transfer process are neglected, namely conduction and convection. For temperatures over 1000K, this is probably justified. Conduction and convection depend linearly upon temperature, while radiation goes up according to the fourth power.


Max™ wrote:That same fund of vibrational energy is also responsible for conductive losses to gases and fluids in contact with the surface, isn't it? So how could a surface at 289 K emit 396 W/m2 AND undergo conductive/convective/evaporative losses adding up to 97 W/m2 (Trenberth et al, 2009)?


I think you're confusing in your model a "fund" of energy with a "fund" of power. It's possible for a box full of jellybeans to lose those jellybeans both by people taking beans off the top every once in a while, AND by beans draining out a hole in the bottom of the box. Both of these methods of loss will tax the "fund" of total beans in the box, but whether or not the jellybeans in the box are at an equilibrium condition will depend on how the total losses compare to whatever source (or fund) continues to replenish the beans over time.

A surface at 289 K emits 396 W/m2 of radiation because that's what black-bodies at 289 K do. It's independent of just how fast or how cold or how conductive a wind blowing across that surface may be. The Stefan–Boltzmann law describes how much energy a body emits via radiation based on its temperature. It is independent of (it is neither constrained by, nor puts any bounds on) other ways that that body may have energy transferred either into or out of itself.

It describes how much radiation a black body emits into a cold ambient environment where other heat transfer methods can be neglected, generally a vacuum or very cold gas where conduction and convection can be ignored completely.

This http://books.google.com/books?id=O389yQ ... &q&f=false goes over conductive AND radiative transfers and it says nothing about them being combined after calculating black body emissions into a vacuum. They even specify that "in a vacuum the only factor influencing the emissions by a black body is temperature", it seems like it would be odd to spell that out specifically if that was the only factor influencing emissions under any conditions, wouldn't it?

There are several sections on the interaction of radiation, conduction, and convection. They note that in some cases they can be calculated independently and then combined, while in others they must be treated together due to the interactions of radiation on gases undergoing convection requiring more complex systems of equations to accurately calculate the results.

Siegel and Howell on Page 338 wrote:The energy transfer is the net radiative exchange and the transfer by free convection. It is equal to the flux q1 that must be added to [the surface] to maintain it at its specified temperature. Since T1 and T2 are given, the hjc must be computed from free-convection correlations and the net energy transfer is, by use of (6-20a),
Image



Pretty sure Siegel and Howell know better than I do.
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Re: Is it possible to have a rational debate on global warmi

Postby Zamfir » Mon Jan 21, 2013 10:27 am UTC

Pretty sure Siegel and Howell know better than I do.

The third author of that book ( 5th edition) is M. Pinar Megcun, who is involved in all kinds of projects to develop low-carbon-emitting energy sources and buildings, and he's chair of a committee to prepare Istanbul for climate change.

I am sure he understands that book as well as you do, yet apparently he takes the greenhouse effect very serious.

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Re: Is it possible to have a rational debate on global warmi

Postby Max™ » Mon Jan 21, 2013 4:51 pm UTC

Wasn't talking about the greenhouse effect though, was I?

I thought I was talking about whether or not it is sensible for Trenberth et al to treat a surface as radiating at full power and undergoing convection without there being a bit of a problem arising due to both of those methods involving the same type of kinetic energy in a solid surface. It's not like one can say "well perhaps the radiation is from vibrational modes while the convection is due to translation modes" here, both are due to the kinetic energy of vibrating molecules in a solid, and the temperature of a solid measures the kinetic energy doesn't it?

It makes more sense though if you start out by properly subtracting the ambient temperature from the surface temperature: P=εσ(289⁴ – 277⁴) gives 63 W/m2~, convection/evaporation in TFK2009 add up to 97 W/m2~ and the incoming solar at the surface is given as 161 W/m2, which is just about 63+97 W/m2 actually. Interestingly enough the energy absorbed by the atmosphere from the sun is around 78 W/m2, and 161+78 W/m2 in would just about balance with 63+97+78 W/m2 out, wouldn't it?
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Re: Is it possible to have a rational debate on global warmi

Postby The Great Hippo » Mon Jan 21, 2013 5:21 pm UTC

I feel a need to repost this question, because I think it is extremely relevant, and I think it's one that you (Max) need to seriously think about:
The Great Hippo wrote:
Max™ wrote:Oh, Hippo, the climate is a system which can be described in terms of energy transfer, thermal properties of various materials, optical properties, thermodynamics, and so on. You wouldn't say the climate is outside the realm of physics, would you?
Of course I would. If nothing climatology dealt with fell outside the realm of pure physics, we wouldn't have a field called 'climatology'; we'd have a field called 'applied thermodynamics'. Climatologists wouldn't be climatologists; they'd be physicists who specialized in heat.

I'll ask again: Why do you think climatology and physics are interchangeable?
The reason you need to think about it is because it's the explicit type of error you agree steve_waterman is making (mistaking math for physics); you seem to be making the exact same type of error, yet insisting that it is not the same type of error.

I think this is something you need to sit down and seriously evaluate for yourself: Why are you presuming climatology and physics are interchangeable? How is this case of you doing so notably different from the case of steve_waterman presuming mathematics and physics are interchangeable?

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Re: Is it possible to have a rational debate on global warmi

Postby Роберт » Mon Jan 21, 2013 5:24 pm UTC

Isn't it a stereotype that physicists always think everything is just physics?
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Re: Is it possible to have a rational debate on global warmi

Postby Iceman » Mon Jan 21, 2013 8:03 pm UTC

Well, Everything is just physics technically, its just beyond the ability to calculate.

My one over-arching question on Global Warming is that we know in the past 500,000 years, the Earth has varied in temperature by over 10 degrees for reasons unrelated to people.

Do we know why those happened, and since they did happen, why are we even trying to preserve the current temperature? Shouldn't we work under the assumption that temperature does vary naturally and so we should be able to adapt to it?

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omgryebread
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Re: Is it possible to have a rational debate on global warmi

Postby omgryebread » Mon Jan 21, 2013 8:36 pm UTC

Iceman wrote:Well, Everything is just physics technically, its just beyond the ability to calculate.

My one over-arching question on Global Warming is that we know in the past 500,000 years, the Earth has varied in temperature by over 10 degrees for reasons unrelated to people.

Do we know why those happened, and since they did happen, why are we even trying to preserve the current temperature? Shouldn't we work under the assumption that temperature does vary naturally and so we should be able to adapt to it?
One climate change in the past (caused by a continent moving) was responsible for the Ordovician-Silurian extinction event, the second largest extinction event to ever occur. Presumably, we're a little better positioned to adapt to climate change than the various simple animals that died then, and our climate change probably won't be that severe, but it's still an awfully big thing and we should probably be a bit concerned.
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Iceman
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Re: Is it possible to have a rational debate on global warmi

Postby Iceman » Mon Jan 21, 2013 9:04 pm UTC

omgryebread wrote:
Iceman wrote:Well, Everything is just physics technically, its just beyond the ability to calculate.

My one over-arching question on Global Warming is that we know in the past 500,000 years, the Earth has varied in temperature by over 10 degrees for reasons unrelated to people.

Do we know why those happened, and since they did happen, why are we even trying to preserve the current temperature? Shouldn't we work under the assumption that temperature does vary naturally and so we should be able to adapt to it?
One climate change in the past (caused by a continent moving) was responsible for the Ordovician-Silurian extinction event, the second largest extinction event to ever occur. Presumably, we're a little better positioned to adapt to climate change than the various simple animals that died then, and our climate change probably won't be that severe, but it's still an awfully big thing and we should probably be a bit concerned.


That is pretty neat, but also I think a bit more extreme than I even meant, and 440 Million years ago.

It always still seems to me 'Climate Change' graphs are like 100-200 years in length... and there's this scary spike at the end, but when you back up to 2,000 years or 500,000 years you kind of see a cycle and repeating rises and drops considerably larger than people are even saying will happen.

Even if we fixed all emissions and badness, won't that still be happening? Why do we truly believe this is just us doing it? Historically it almost always seems CO2 rises as a result of temperature changes and not vice versa and large changes tend to be geological events or Solar/Space events.


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