When looking at these graphs, it pays to take a peek at who exactly is behind them. Modeling the costs and benefits of different forms of energy (especially environmental costs) is extremely easy to fudge. There are all sorts of assumptions you have to plug in to the model where you could covertly insert a policy bias. If the 'measurer' had an agenda, it wouldn't be hard for them to push the figures one way or another and still keep the model looking clean-ish from the outset.
Bearing that in mind, it's worth pointing out that Exxon-Mobil is a major donor to the brookings institute - they're also part of the group ALEC that has been leading a massive attack on rooftop solar in the last 18 months.
One of those attacks, for instance, has been to increase the price by slapping up to 35% tariffs on Chinese panels through (mostly false) accusations of dumping. I wouldn't be terribly surprised if this were counted in the cost model, but subsidies were discounted.
Another thing they've been doing recently is to try to 'greenwash' natural gas - to make it look like the cleaner alternative to coal to capitalize on the fracking boom. One of the assumptions I can virtually guarantee that they've made here, for instance, is that global warming effect of methane leakage (which is very significant) has been entirely discounted.
They suggest his biggest distortions are using a) a historical figure for wind costs averaged over a decade even though it's got much cheaper over that time span and b) counting each year in that decade equally even though the amount of wind energy produced grew rapidly, c) using a figure from a press release for gas capacity rather than actual figures which would be 50% lower.
The greenhouse effect is reasonably well understood and methane is a potent greenhouse gas. We know that man made pollution is highly correlated with global warming and we know that greenhouse gasses cause the globe to warm. The only thing we don't know for certain is if there is another currently unknown cause with a larger contribution to global warming.
> The greenhouse effect is reasonably well understood
Except that it doesn't stand even basic scrutiny. 10 meters high layer of CO_2 with current concentration already absorbs 99,94% of IR radiation, so whatever made it above fourth floor would be swallowed by next floors. Any change to the concentration of CO_2 makes no difference on Earth's radiation.
> and methane is a potent greenhouse gas.
Water is even more potent, as I know. We don't emit much water to the atmosphere. And guess what? It's there, even more than CO_2 and methane combined together.
And now quick question: how are you sure that Sun's increasing activity is not the reason of climate change?
And a hint: four centuries ago Batic Sea was freezing seasonally, so people could even build inns on it. Now there's little ice on Baltic since mid-1800's. The climate changed drastically, was it industry's fault as well? 19th century industry was not developed enough yet to affect whole climate.
> We know that man made pollution is highly correlated with global warming and we know that greenhouse gasses cause the globe to warm.
We know it is highly correlated, true. Correlation is not causation, though. It is basic logic.
Then, we do not know that greenhouse gasses cause the global warm. It is merely a hypothesis, and given the historical facts, it doesn't stand the Occam's razor principle.
> The only thing we don't know for certain is if there is another currently unknown cause with a larger contribution to global warming.
No. The first thing we don't know is whether the hypothesis is actually true. It's unverifiable at best. There are plenty of possible effects in thermodynamics that would easily make the noise in measurements above the level of changes that are announced for greenhouse effect. We have no way to verify the claim the greenhouse effect takes the place, all the argument about it revolves around some mental model, which nobody tell is correct.
> 10 meters high layer of CO_2 with current concentration already absorbs 99,94% of IR radiation, so whatever made it above fourth floor would be swallowed by next floors. Any change to the concentration of CO_2 makes no difference on Earth's radiation.
Do you have a source for this?
>Water is even more potent
Yes and that would be a huge problem if it built up instead of falling out of the sky.
>how are you sure that Sun's increasing activity is not the reason of climate change?
This is actually what I was thinking of when I said "we don't know for certain is if there is another currently unknown cause with a larger contribution to global warming" though I believe this particular theory has been debunked.
>four centuries ago Batic Sea was freezing seasonally
You are referring to the little ice age which was primarily a localized event and therefore not caused by changes in the greenhouse effect or solar radiation.
http://en.wikipedia.org/wiki/Little_Ice_Age
>We know it is highly correlated, true. Correlation is not causation, though.
I completely agree. The fact that they are correlated does not give us a causal link. The fact that green house gasses increase temperature does. The only missing piece here is how much of the increased temperature is caused by our greenhouse gas emissions and how much is caused by other unidentified forces.
>There are plenty of possible effects in thermodynamics that would easily make the noise in measurements above the level of changes that are announced for greenhouse effect.
I completely agree. When I said there could be an unknown effect, I did not mean to imply such an effect would be outside of "possible effects in thermodynamics".
>We have no way to verify the claim the greenhouse effect takes the place
Actually we can. We can measure the radiation before it hits earth, when it hits the ground and when it leaves the atmosphere as well as measure what radiation is absorbed and emitted by various gasses. We don't have a perfect understanding of the green house effect, but we can observe it in action.
>> 10 meters high layer of CO_2 with current concentration already absorbs 99,94% of IR radiation, so whatever made it above fourth floor would be swallowed by next floors. Any change to the concentration of CO_2 makes no difference on Earth's radiation.
> Do you have a source for this?
"The roles of carbon dioxide and water vapour in warming and cooling the earth's troposphere", Jack Barrett. Maybe there's not the number (99.94%), but it says about absorption saturation on the first 100 meters above the ground.
> Yes and that would be a huge problem if it built up instead of falling out of the sky.
It would be not. Maybe you don't know it, but water is already present in the atmosphere at the level of ground. Moreover, while some of water "falls out of the sky", some other part of it vaporizes at the same time. It doesn't disappear from the air.
> This is actually what I was thinking of when I said "we don't know for certain is if there is another currently unknown cause with a larger contribution to global warming" though I believe this particular theory has been debunked.
At this point it doesn't matter whether this particular theory has been debunked or not. You say that "we don't know for certain is if there is another currently unknown cause with a larger contribution to global warming". So we don't know if the global warming is actually caused by greenhouse effect. There's no magic in greenhouse effect that would cause it important when proven unimportant. Having this, it's way, way too early to panic about the greenhouse effect.
> The fact that green house gasses increase temperature does [give causation].
It would, if it was fact. It's merely a hypothesis that these gasses increase the temperature of Earth. And again, it doesn't stand direct measurement with calculations (i.e. absorption saturation).
> The only missing piece here is how much of the increased temperature is caused by our greenhouse gas emissions
...if affected by these emissions in any way over measurement error...
> and how much is caused by other unidentified forces.
So basically, we don't know if there are any other forces, but it must me human emission that causes global warming. So we focus on CO_2 and methane, which is nowhere near what water can absorb.
>> We have no way to verify the claim the greenhouse effect takes the place
> Actually we can. We can measure the radiation before it hits earth, when it hits the ground and when it leaves the atmosphere as well as measure what radiation is absorbed and emitted by various gasses.
You know that this doesn't tell whether the greenhouse effect takes place? It only shows how much radiation is absorbed before entering the atmosphere and after leaving it. We have no way of checking if increasing CO_2 or methane concentration affects the radiation absorption. Sorry, but there are too many variables to make this a realiable experiment, and having effectively only one data point is too little to draw any conclusions.
Thank you for the source. It seems to claim that so little heat makes it through the atmosphere that more insulation won't make a difference. Given the fact that IR cameras in orbit can measure surface temperature, I think a significant amount of heat must be escaping. This seeming contradiction may simply be my misunderstanding. Can you clarify the point you are making with that article?
>water is already present in the atmosphere
Yes water in the atmosphere is at an equilibrium. Adding more water has only a short term effect unless it somehow changes that equilibrium. Water has a large greenhouse effect and without that effect Earth would be much colder. If that effect were to increase Earth would get hotter, but fortunately the excess water simply falls out of the sky instead. That's why it is so important that water falls out of the sky. CO2 on the other hand is not at an equilibrium thus its effect can build up over time.
>It would, if it was fact
It is an observation. We can literally observe it happening. That does not tell us precisely how it would function under different conditions (such as increased CO2), so for that we must rely on theory. That theory, because it is based on flawed human understanding is fallible. Our conclusions about man made global warming are less than 100% certain.
>There's no magic in greenhouse effect that would cause it important when proven unimportant. Having this, it's way, way too early to panic about the greenhouse effect.
I am of course not recommending panic. If the greenhouse effect were proven unimportant (and either I understood said proof, or some reasonable portion of the scientific community agreed with it) then I would stop worrying about CO2 emissions. Given that theory explains why we should expect green house emissions to increase temperature, the strong correlation between the two and the lack of other credible explanations, I come to the obvious (though not completely certain) conclusion.
> Adding more water has only a short term effect unless it somehow changes that equilibrium.
It doesn't matter. The water already present in the atmosphere absorbs almost all IR radiation. Add anything and you won't get bigger greenhouse effect, assuming it actually works.
> Water has a large greenhouse effect and without that effect Earth would be much colder.
Or not. We don't know it. You said yourself that we don't know if there is any bigger effect taking place. And the greenhouse effect is mainly accepted among climatologists. Physicists who work on thermodynamics don't quite agree the very reasoning about energy balance done by climatologists is credible at all.
> If that effect were to increase Earth would get hotter, but fortunately the excess water simply falls out of the sky instead.
Really? What "excess" do you mean? You know that it's not only the "excess" which causes IR absorption? And if there's little radiation left to be absorbed, adding more greenhouse gases doesn't make the temperature grow.
>> It would, if it was fact
> It is an observation. We can literally observe it happening.
No. It's just a hypothesis that greenhouse effect takes place. We do not have enough data to confirm the effect.
> That does not tell us precisely how it would function under different conditions (such as increased CO2), so for that we must rely on theory.
And there goes f*ck your claim that it was a fact.
> The water already present in the atmosphere absorbs almost all IR radiation
This does not seem to be correct. The earth's is gaining a significant amount of energy from the sun. Since temperature is at an equilibrium we can assume it is losing a very similar amount of energy. We know that the earth gives off less (visible) light than it receives so the obvious explanation is that the earth is giving off a significant amount of heat. We can also directly observe heat leaving the earth from IR cameras in orbit.
> No. It's just a hypothesis that greenhouse effect takes place.
> And there goes f*ck your claim that it was a fact.
You misunderstand me. It is a fact that the green house effect is happening. You yourself continue to insist that is is happening with statements like "The water already present in the atmosphere absorbs almost all IR radiation". Observing it happening is not the same as knowing how it would change in different conditions. That part is theory.
Let me give a similar example:
We can observe that the sun heats the earth. That is a fact. We have a theory that if the sun were to go out, the earth would get colder. Since the sun is still shining we cannot observe what would happen if the sun went out, so we deploy reason instead of direct observation. You could insist that the earth would stay the same temperature without the sun shinning and point out that we can't know for sure because it hasn't happened yet. Any statement we make about the future is not an observed fact because the future has not happened yet, but e can draw reasonable conclusions about the future.
That is a reasonable sounding argument, much more reasonable than I expected before looking into it. I also came across explanations such as this one: http://clivebest.com/blog/?p=1169 which explains why increased CO2 will still increase the greenhouse effect.
An appeal to authority is not the strongest argument, but there is a near universal consensus among the scientific community that increased CO2 will increase the greenhouse effect.
Bearing that in mind, it's worth pointing out that Exxon-Mobil is a major donor to the brookings institute - they're also part of the group ALEC that has been leading a massive attack on rooftop solar in the last 18 months.
One of those attacks, for instance, has been to increase the price by slapping up to 35% tariffs on Chinese panels through (mostly false) accusations of dumping. I wouldn't be terribly surprised if this were counted in the cost model, but subsidies were discounted.
Another thing they've been doing recently is to try to 'greenwash' natural gas - to make it look like the cleaner alternative to coal to capitalize on the fracking boom. One of the assumptions I can virtually guarantee that they've made here, for instance, is that global warming effect of methane leakage (which is very significant) has been entirely discounted.