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Forum » SpaceEngine » Off-topic Discussions » General Global Warming / Climate Change Discussion (because a thread for this was long overdue)
General Global Warming / Climate Change Discussion
WatsisnameDate: Monday, 30.09.2013, 18:43 | Message # 16
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The full AR5 WGI report is now available. It is 2216 pages long -- more than twice the length of AR4. blink

Edit: Man, this is sad. Although these pages are absolutely rich with great information, the visual presentation is awful. I much preferred AR4's style; it was much easier to navigate. Then again this is still just the final draft, so maybe the end result will look better.





 
midtskogenDate: Monday, 30.09.2013, 20:18 | Message # 17
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I promised to get back to how enormous amounts of money are thrown at actions returning very little. Some years ago our politicians decided that carbon capture and storage at a gas power plant (Kårstø/Mongstad) is a good idea and well used money. It produces 420 MW (estimated 354 MW with CCS). The project was launched by the prime minister as Norway's "moon landing". A showcase. A technical achievement and an example for the rest of the world.

Theoretically it is possible to capture around 85% of CO2 that otherwise would go into the atmosphere. Since this takes vast amounts of energy, the effectiveness of the plant goes down, so it has to produce more and the real effectiveness of the capture per usable energy produce then hardly gets above 80%. Still, it would be cool if it can be done. It's a pretty direct way to cut down emissions. Let's disregard the pollution increase of other things (like NOx). And that it does nothing towards the real target, to move away from fossil fuel apart from taking resources away from solving the real problem. The problem then is the price. This peer reviewed paper from 2011 tries to estimate the cost effectiveness. For instance, it finds that the carbon offset price needs to be about $1000 per tonne in 2036 in order to make the project profitable. Which seemed pretty ridiculous in 2011 and totally now since the carbon offset price and trading have pretty much completely collapsed. Worse, costs and delays have totally spiralled out of control. Well over one billion $ have been spent on testing carbon capture, close to the original budget for the whole project, but no actual construction has yet been done. As it stands now, most likely much of if not all of the project will be scrapped. We don't know the end of this story yet, but it's really hard to imagine this as being anything but a total economical disaster. Environmentally, the project completed or not causes much local pollution and if it eventually gets to capture any CO2, the question must be asked how much more other actions could have done given the same resources.





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WatsisnameDate: Monday, 30.09.2013, 21:08 | Message # 18
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Quote
the question must be asked how much more other actions could have done given the same resources.


The answer is quite a lot. Carbon capture itself is a thermodynamical nightmare requiring lots of energy. (I'm also curious how it fares when applied to other industrial sources of CO2. One that doesn't get much attention despite the large contribution is the manufacture of cement.)

Instead of, or perhaps in addition to, carbon capture, are a number of strategies for the energy sector that economically make a lot more sense. The set of strategies laid out by the IEA is:

-Adopting specific energy efficiency measures (49% of the emissions savings).
-Limiting the construction and use of the least-efficient coal-fired power plants (21%).
-Minimizing methane (CH4) emissions from upstream oil and gas production (18%).
-Accelerating the (partial) phase-out of subsidies to fossil-fuel consumption (12%).





 
midtskogenDate: Tuesday, 01.10.2013, 06:16 | Message # 19
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Carbon capture itself is a thermodynamical nightmare

And that's not news. Launched as Norway's "moon landing", it's hardly a more direct way to say that we knowingly do not pick the low hanging fruits, but the opposite (i.e. "not because they are easy, but because they are hard"). The symbolic value is huge, if successful. One reason for doing this no doubt the fact that Norway with its population of 5 million people is the world's third largest oil exporter, and so indirectly responsible for large amounts of emissions, so this is more about feeling better than results. Also troubling, while one can argue that while the moon landing was ridiculously expensive, we're learned much from it (though the world might have had more space technology today if the resources had gone into satellite technology, space laboratories, etc). But in the case of CCS what we learn is ultimately just useful for squeezing out the last drops of oil and gas of earth which is not the long term goal and not a necessary part of the road towards it. Even now when "scandal" is written all over the wall, environmentalists refuse to accept reality and if Mongstad fails, they look to use the experience to capturing carbon on Svalbard. Doing it in the high arctic where the infrastructure is much less and very expensive may seem odd, but again the symbolic value is huge in an area where polar ice is retreating faster than anything seen in living memory. There exists a vision to make Svalbard, whose main industry is coal production, "carbon neutral". Costs matter less.

Too often reason and whatever is attempted to accomplish goes out with the bathwater when CO2 is involved. I have a growing feeling that CO2 and reason don't mix. And when you add to that that the climate sensitivity is uncertain and that the effects of it are uncertain too, CO2 is likely a distraction.

What we really need to figure out is a sustainable way to bring prosperity to a 10+ billion population of Earth. We're moving with such a momentum now that we don't have many centuries to figure it out. We should accept the risk of breaking a few eggs on the way (and also accept the possibility that there might not be that many broken after all, or that are omelettes to be had as well). But now we're more occupied developing technology for making unbreakable eggs.





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WatsisnameDate: Tuesday, 01.10.2013, 06:58 | Message # 20
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So... let me make sure I understand you correctly; I'm just trying to follow your trail of discussion here.

Your position is that the IPCC is a waste of money because your country is enacting economically stupid policies despite there being plenty of information available on what the economically smart polices actually are, and now you are re-raising the bit about the uncertainty in climate sensitivity despite everything I've pointed out on page one of this thread.

Is this right?





 
midtskogenDate: Tuesday, 01.10.2013, 08:35 | Message # 21
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Quote (Watsisname)
Is this right?

Not very. I'm all for science and scientific contribution, but politically I don't think the IPCC is very helpful currently. I'm arguing that politics is too much in the power of symbolism and display, possibly aided by the hobby horses of environmentalists. If you have good evidence of the contrary, please provide it. While IPCC may have important messages, the risk of adding fuel to pointless dreams must be considered as well. I'm also making the point that CO2 emission is a part of a larger problem, the world's energy needs as we move towards another goal, a world without poverty, the key to a sustainable population. If we solve the larger, the smaller follows naturally, but it's less so the other way. A wider perspective should lead us faster to the goal.

Regarding climate sensitivity, the importance of the uncertainty is amplified by a couple of things besides it being part of a secondary and narrow target. First, I hold that air temperature, in the range in question, is not a very good metric of the Earth's environmental health. Second, that the opportunities of a CO2 rich, warm world are comparatively much neglected. Perhaps mainly due to the issue having become so polarised.





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HarbingerDawnDate: Tuesday, 01.10.2013, 08:55 | Message # 22
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Quote (midtskogen)
First, I hold that air temperature, in the range in question, is not a very good metric of the Earth's environmental health.

No one here is using it as a metric of Earth's environmental health. We're simply saying that the Earth is warming, and that said warming will have significant and negative consequences for humanity, and thus we cannot ignore it and should try to limit it since it's our activity which is causing it in the first place.

Quote (midtskogen)
Second, that the opportunities of a CO2 rich, warm world are comparatively much neglected. Perhaps mainly due to the issue having become so polarised.

In order to entertain thoughts of what benefits there might be with a warmer Earth, you must first honestly tell me that it is acceptable to willingly allow sea level rise to displace millions of people and cause billions of dollars in economic damage in this century alone, creating a mass refugee crisis, not to mention the effects of droughts and altered precipitation patterns, which will also undoubtedly bring harm and hardship to a lot of people. The climate as it is now has been as it is for thousands of years. People have distributed themselves and established their civilizations around that climate, so very few people stand to lose if the climate remains unchanged, or only changes a little. Unless you are willing to condemn many millions of people to hardship and suffering on the chance that some other people might encounter prosperity, then there is no point in carrying on any "maybe we should let it get warmer" discussion.





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midtskogenDate: Tuesday, 01.10.2013, 10:16 | Message # 23
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Quote (HarbingerDawn)
We're simply saying that the Earth is warming, and that said warming will have significant and negative consequences for humanity,

And I will argue that warming isn't the only thing doing that, and that not only humanity should be considered. Since we can't fix everything, we must be conscious about the best returns and the order in which to do things.

Quote (HarbingerDawn)
... willingly allow sea level rise to displace millions of people and cause billions of dollars in economic damage in this century alone, creating a mass refugee crisis, not to mention ...

Reality check: oceans will rise and erode coastlines regardless. Coastlines are not static and we have and must continue to adapt to that. Fortunately, the rise rate is measured in cm per century, not metres (unless you follow Hansen/Gore), at a pace compatible with city and land planning. That's where money needs to be spent, since it's necessary anyway, not in postponing. You invite me to ask back: how many million people are you willing to condemn by diverting money from adaptation needed for sure into postponing actions? I hope you see that the discussion is taking an ugly direction by resorting to that kind of rhetorics. Let's keep it civilised, shall we? We're not discussing very different targets, just what the most effective ways of achieving them are. I'm trying to speak for the broader picture, and for some optimism.





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Edited by midtskogen - Tuesday, 01.10.2013, 10:16
 
HarbingerDawnDate: Tuesday, 01.10.2013, 10:31 | Message # 24
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Quote (midtskogen)
And I will argue that warming isn't the only thing doing that, and that not only humanity should be considered.

Of course it's not the only thing that is. But it is one of the things that is, and thus should not be ignored.

Quote (midtskogen)
Reality check: oceans will rise and erode coastlines regardless.

Incorrect, certainly not on a timescale of decades and single-digit centuries. There are cities in the world which have had their present positions near the coast or below sea level for centuries or more. Now we're looking at them being destroyed within 200 years. That is not part of the natural progression of climate, nor would it be desirable even if it were.

Quote (midtskogen)
Coastlines are not static and we have and must continue to adapt to that.

But only to whatever extent is absolutely necessary. Saying we should not do anything to mitigate these effects is like saying we should allow an asteroid to impact Earth and cause regional devastation simply because these things happen and it's best to just adapt to it.

Quote (midtskogen)
Fortunately, the rise rate is measured in cm per century, not metres

Do you have any specific evidence supporting a sea level rise of only centimeters being likely during the 21st century, as opposed to 1 meter or more?

Quote (midtskogen)
You invite me to ask back: how many million people are you willing to condemn by diverting money from adaptation needed for sure into postponing actions?

I don't see that the two are mutually exclusive. There is more than enough money in the world to fund both, and spending that money on these problems now would be much less expensive than waiting until later. Also, it's not a "postponing action", it's a preventative action. We're not trying to prevent shorelines from ever changing, we're trying to prevent them from changing dramatically over a relatively short time scale due to unnecessary human climate meddling. I am not talking about trying to postpone gradual natural change.

Quote (midtskogen)
I hope you see that the discussion is taking an ugly direction by resorting to that kind of rhetorics.

It's not rhetoric. The science - at least as I understand it - supports the claims I'm making. I am attempting to raise valid concerns here, just as you are.

Quote (midtskogen)
Let's keep it civilised, shall we?

Of course we should keep it civilized, and so far I don't see anyone having departed from the realm of civilized discussion.

Quote (midtskogen)
We're not discussing very different targets, just what the most effective ways of achieving them are

There are certain fundamental positions and premises that must be discussed before getting to that, which is why I brought up the issue of what possible futures are and are not acceptable to each of us. If we can't agree on what effects of climate change are acceptable or not, or even what those effects might be, then we have no basis for discussing what the best actions to take are for improving the general human condition.





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Edited by HarbingerDawn - Tuesday, 01.10.2013, 10:35
 
midtskogenDate: Tuesday, 01.10.2013, 11:15 | Message # 25
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There are cities in the world which have had their present positions near the coast or below sea level for centuries or more.

Of course. Even millennia. Cities are constantly renewed and almost entirely rebuilt every couple of centuries on top of the old rubble. Cities change faster than the sea, so sea level rise at the pace we're speaking about is not necessarily a concern. Erosion is a bigger issue since its effects are more unpredictable. Or silting and sediments which can remove the city from the shoreline. I've previously mentioned Dunwich, a capital and international port rivalling London at the time it was lost to the sea, and Ostia, the port of Rome that had to be given up.

Quote (HarbingerDawn)
Do you have any specific evidence supporting a sea level rise of only centimeters being likely during the 21st century, as opposed to 1 meter or more?

AR4 summarises the projected 21th century likely sea level rise this way:

Scenario B1: 18 to 38 cm
Scenario A1T: 20 to 45 cm
Scenario B2: 20 to 43 cm
Scenario A1B: 21 to 48 cm
Scenario A2: 23 to 51 cm
Scenario A1FI: 26 to 59 cm

I think the Hansen/Gore projections have been fairly well debunked. Also note the small differences between the scenarios. Assuming a difference in the range of 10-20 cm in a century depending on the scenario [taking that as what we can do something about], and differences in cost for the different scenarios not being insignificant, I think talk of willingly sacrificing millions, etc, is a bit over the top.





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Edited by midtskogen - Tuesday, 01.10.2013, 11:58
 
WatsisnameDate: Tuesday, 01.10.2013, 18:53 | Message # 26
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That is correct, current scientific consensus is that >1m of sea level rise by 2100 is unlikely. However, even the moderate (tens of centimeters) of rise that is projected poses significant challenges to coastal populations, and yes, it does affect millions. We also can't treat sea level rise as being linear except over short-term intervals. As I described last page, at the rate we are going we will soon be faced with the commitment to several meters of rise due to the loss of Greenland's and some of Antarctica's ice. By paleoclimate evidence, a 2 degree warmer world has sea levels 5 to 10 meters higher than present, and a simple look at mass balance and thermal expansion is consistent with this picture.

Quote
Regarding climate sensitivity, the importance of the uncertainty is amplified by a couple of things besides it being part of a secondary and narrow target. First, I hold that air temperature, in the range in question, is not a very good metric of the Earth's environmental health. Second, that the opportunities of a CO2 rich, warm world are comparatively much neglected. Perhaps mainly due to the issue having become so polarised.


I'm afraid I find fault with both of these points. Although there have been times in Earth history where life has flourished during high-CO2/houthouse climates, one must not neglect the rapidity of the changes involved, for which there is absolutely no comparison to the current changes. And I don't know of any good metric for such an abstract concept as Earth's environmental health, except perhaps population and number of species. Instead, we quantify the effect of increased global temperatures by a wide range of impacts on humanity and ecosystems, as I have described in detail in previous discussions of this subject. The short list looks like this:
-freshwater availability
-temperature
-precipitation
-soil moisture and evaporation; agriculture; food availability
-sea level
-enhanced storm surge vulnerability
-extreme weather
-ocean acidity
-species migration
-species loss
-pest and disease vectors
-air quality
-energy demand (e.g. the greater demand for cooling which exceeds reduced demand for heating by at least a factor of 2)

Most of these metrics see net negatives, and with nonlinear dependence on increased global temperature. Therefore the increase in global temperature is the root cause of a wide range of problems currently facing humanity, and policies that favor reduced emissions and adaptation to the changes we are already committed to are most wise. And as pointed out with the IEA report, there exist economically-favorable policies that both move us toward sustainable energy and simultaneously reduce emissions, yet many governments are, for whatever reason, mostly failing to follow those policies.

Perhaps what the governments need is a swift and overwhelming demand for the appropriate action by its citizens, but a largely docile and uninformed population appears to be preventing that, which brings us back to education. The IPCC is doing its best to educate by putting this information out there, so calling it worthless is completely crazy to me.





 
midtskogenDate: Tuesday, 01.10.2013, 20:20 | Message # 27
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However, even the moderate (tens of centimeters) of rise that is projected poses significant challenges to coastal populations

You miss my main point, that the rise is happening anyway. Even if we pick the IPCC extremes squared, contrasting B1 with A1FI and pick the high end of the projections, the difference is only 21 cm. That's roughly equal to the estimated rise that has taken place in the last 150 years, or for that matter comparable to the sea level change (although negatively) locally over here that has taken place during my lifetime. And even in a B1 scenario we would in this case have a 38 cm rise, much larger than the difference that we theoretically could make at some unknown cost. Then recall that this isn't a debate whether there will be bad local effects somewhere, but about what's more cost effective. If you on behalf of the world's tax payers had a trillion dollars to spend on sea level rise issues over the next 100 years, how would you spend the money?

By the way, what about wars, what do people here think of the Nobel peace prize having been awarded to Al Gore and the IPCC? Far fetched connections to wars or well deserved?





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Edited by midtskogen - Tuesday, 01.10.2013, 20:22
 
HarbingerDawnDate: Tuesday, 01.10.2013, 20:28 | Message # 28
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Quote (midtskogen)
AR4 summarises the projected 21th century likely sea level rise this way:

Concerning the AR4 projections, the AR5 draft has this to say about them:

Quote (AR5 Draft, Ch. 13)
The AR4 (Meehl et al., 2007) presented process-model-based projections of GMSL rise for the end of the 21st century, but did not provide a best estimate or likely range principally because scientific understanding at the time was not sufficient to allow an assessment of the possibility of future rapid changes in ice-sheet dynamics (on timescales of a few decades, Section 4.4.5). Future rapid changes in ice-sheet outflow were consequently not included in the ranges given by the AR4. For the SRES A1B scenario, the AR4 range was 0.21–0.48 m, and for the highest emissions scenario, A1FI, it was 0.26–0.59 m. The AR4 also noted that if ice-sheet outflow increased linearly with global mean surface air temperature, the AR4 maximum projections would be raised by 0.1–0.2 m. The AR4 was unable to exclude larger values or to assess their likelihood.

Since the publication of the AR4, upper bounds of up to 2.4 m for GMSL rise by 2100 have been estimated by other approaches, namely semi-empirical models (SEMs, Section 13.5.2), evidence from past climates (Section 13.2.1), and physical constraints on ice-sheet dynamics (Sections 13.4.3.2 and 13.4.4.2). The broad range of values reflects the different methodologies for obtaining the upper bound, involving different constraining factors and sources of evidence. In particular, the upper bound is strongly affected by the choice of probability level, which in some approaches is unknown because the probability of the underlying assumptions is not quantified (Little et al., 2013b).

Looking at the final draft of AR5, I find these ranges listed for projected sea level rise as of 2100:

0.43 [0.28–0.60] m (RCP2.6)
0.52 [0.35–0.70] m (RCP4.5)
0.54 [0.37–0.72] m (RCP6.0)
0.73 [0.53–0.97] m (RCP8.5)

Generally higher than in AR4, but still much below a meter. They also state that other factors (principally ice sheet melting) could contribute to additional rise, but express with medium confidence that any such additional rise would amount to no more than "several tenths of a meter". Not sure what exactly several means but using an upper limit that gives a worst case sea level rise by 2100 of about 150 centimeters. So probably significantly less than a meter in any case, though levels greater than one meter cannot be ruled out.

They don't speak of it in the report, I suspect since it's hard to do more than speculate at this point since we don't know which scenario will play out, but a rise of 2+ meters by 2200 doesn't seem implausible, and that would begin to cause serious problems.

So with regards to sea level rise, it seems that you're right and it's not serious issue for the immediate future, but it's worth taking into consideration, especially over long timescales.

I also want to address the other issue I brought up - changing precipitation patterns and changing temperatures - but I'll have to do that in a later post.

Quote (midtskogen)
By the way, what about wars, what do people here think of the Nobel peace prize having been awarded to Al Gore and the IPCC? Far fetched connections to wars or well deserved?

...what? What wars? What does that have to do with the Peace Prize of 2007? I don't understand what you're saying here.





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midtskogenDate: Tuesday, 01.10.2013, 20:45 | Message # 29
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Generally higher than in AR4, but still much below a meter.

You need to look at the portion that we can change (around 30 cm) assuming that all scenarios are realistic, and also compare that with the unavoidable part (larger in all scenarios).

Quote (HarbingerDawn)
What does that have to do with the Peace Prize of 2007?

The premise is that climate change will lead to conflicts and wars. If raising the awareness reduces the climate change, wars will be avoided and for which a peace prize is well deserved.

Is that premise sound?





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WatsisnameDate: Tuesday, 01.10.2013, 20:49 | Message # 30
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Quote (midtskogen)
You miss my main point, that the rise is happening anyway.


I apologize for missing your main point. But by observation, the rate has accelerated since pre-industrial rates, as pointed out in AR5 as well as previous reports. So I don't think the statement 'the rise is happening anyway' really paints a complete picture that is faithful to evidence. Furthermore, the projections (and thank you Harbinger for quoting the updated projections in AR5) still negatively impact millions of people around the globe.

Quote
Then recall that this isn't a debate whether there will be bad local effects somewhere, but about what's more cost effective. If you on behalf of the world's tax payers had a trillion dollars to spend on sea level rise issues over the next 100 years, how would you spend the money?


This is an excellent question. In determining how to spend the money, I would advocate a metric of minimizing greenhouse gas emissions, minimizing the vulnerability to changes we are already committed to, and maximizing the efficiency of energy production and usage, for a given quantity of capital. This naturally leads us to the set of policies described by the IEA, and if we speak a little more broadly (going beyond just the energy sector), it leads us to the set of policies described by the IPCC's WGIII reports.

Added:
Quote
The premise is that climate change will lead to conflicts and wars. If raising the awareness reduces the climate change, wars will be avoided and for which a peace prize is well deserved.

Is that premise sound?


Seems sound to me, though I don't know if awareness alone will prove to be enough. There is also talk going on of current conflicts in the middle east being attributable at least in part to climate change (IIRC fresh water availability, mostly), but I am not qualified to speak to the validity of these claims. Just that people a lot more knowledgeable than myself seem to think so.





 
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