Like it's the climate scientists who design and implement CO2 abatement policies? No, that's economists and politicians. Geoengineering is an ENGINEERING project. Scientists might tell engineers how much needs to happen, but they're not the ones who would design, build, or deploy the devices.
Besides, if you're insinuating that climate geoengineering is all a scientific conspiracy to get funding dollars, that's pretty lame. Even if you're a conspiracy nutjob, how is inventing a cheaper solution (geoengineering) than existing plans (emissions abatement) going to get them more money?
Because of the risk of side effects. Massively fertilizing ocean plankton, for instance, will undoubtedly have rather large effects on ocean ecosystems which all depend on plankton. It's rather questionable whether we can even fertilize the ocean enough to sequester most of the CO2 we'll put into the air over the next couple centuries; it only works insofar as iron continues to be the limiting nutrient. Once you dump tons in, it's no longer limiting. Likewise there are problems with other geoengineering schemes, such as aerosol geoengineering; the problem there is that the control (aerosols) operates on a very different timescale than the carbon cycle, so you have to guarantee that you can keep geoengineering going, uninterrupted, for centuries.
As for self referencing.. If you're legitimately advancing your previous work, why not?
There's nothing wrong with self referencing. But it shouldn't be used to quantify your paper's impact on the rest of the academic community. You can cite yourself all you want, for legitimate reasons, but that doesn't say anything about what impact your paper is having on anyone else.
I didn't say there weren't good reasons to self-cite. I said that self-citation shouldn't count as part of the impact factor, even if it's legitimate self-citation. A paper's impact should measure the paper's impact on OTHER researchers. If I'm the only one who cites my own paper, my citations may be for legitimate reasons (building on my previous work), but that doesn't mean I'm having an impact on the rest of the community.
I know what "endothermic" means. And you don't know what the hell you're talking about. We're not talking about cool mist wafting up from the surface due to circulation. We're talking about sudden transport to a cooler environment before the water droplets have time to cool or evaporate. Your ignorance of thermodynamics doesn't change the fact that water has been transported to a cooler environment, and not in a slow way that allows it to re-equilibrate before it gets there.
Excluding references to the same journal is too harsh a criterion, since a lot of high quality papers get published in high quality journals. What should be perhaps excluded, though, is self-citation (whether to your own articles in the same or a different journal). Also, papers published in a journal by a journal editor shouldn't count.
The only way to 'inject' water into the atmosphere and have it radiate heat is to boil it.
Uh, no. You spray it at high velocity. If it reaches high altitudes before it has had time to cool, it will be warmer than its surroundings and will cool there. It will radiate its latent heat.
Yes, it is La Nina. It's true that the PDO is in its cool phase, as the JPL press release notes. It has been for some time now. That's not why 2008 is a cold year, relative to recent years. The reason why 2008 is a cold year relative to recent years is because most of this year was in or recovering from a La Nina. (And no, it's not a "record cold year" either. 2008 has been still quite warm, globally speaking, compared to most years in the 20th century.) The PDO cools the Pacific too, so the La Nina added on top of that. But the PDO doesn't explain why this year was cooler than recent years, because recent years were also in a PDO cool phase. The PDO influences the climatological background state, but the interannual temperatures are modulated by ENSO.
As I said, the PDO can influence the likelihood/magnitude of a La Nina, but if there's a big temperature difference between one year and the next, it's not fundamentally due to a multidecadal oscillation. Multidecadal oscillations don't have big changes from one year to the next.
Orbital/solar variations are far too weak/slow to explain the modern warming period. Nor is it explicable by surface heating from the oceans, as the oceans indicate that they are gaining heat, not losing it.
We are having a cold year because of La Nina (ENSO is not the PDO, although the PDO affects ENSO variability). ENSO is a large but transient phenomenon. There is no evidence that multi-decadal ocean or solar cycles have a larger influence on surface temperatures than greenhouse gases, given their abject failure to explain the observed temperature trends.
The water vapor is cooler than the surrounding areas.
No, it's not. It's warm surface water which is injected high into the cool atmosphere. It cools there and radiates heat. Some of that heat escapes to space.
How is this vapor going to be lofted to higher and cooler altitudes?
It's mechanically injected. That's the point of this proposal.
That graph shows long term trends. Look at the key.
You are deeply confused. The long-term trend in ice extent is strongly negative. A year with above-average winter ice extent does not disprove this trend.
Furthermore, what exactly is required to disprove this theory? Growing ice?
Not directly. Ice can grow in a warming world; it depends on the temperature-precipitation balance, winds, etc. This is particularly true of central contintental locations. However, a long term reversal in, say, sea ice melt would contradict warming polar temperatures. Of course, cooling polar temperatures would contradict warming polar temperatures: you don't need ice melt to measure that.
Reducing temperature?
A long term reduction in temperature (say, 20-30 years), in the presence of increasing CO2 and in the absence of other cooling factors like increased volcanic activity, would contradict the theory.
CO2 lagging temperature in the geological record?
No.
I don't think it does. Unless of course you attribute previous temperature rises to CO2, which you absolutely cannot.
The instrumental record of temperature rise through the 20th century absolutely can be attributed largely to CO2.
If you've read the Wegman report, or follow Steve McIntyre's blog
I do both.
(two people better versed in the mathematics of statistical analysis than any Climate Scientist),
You're hilarious.
you will see that they do not concur either.
You're still confused. They don't like the hockey stick. That doesn't mean that they disagree that CO2 causes warming. The Wegman Report didn't address that, and I remember Steve McIntyre noted on one of his comment threads last year that he finds the CO2-warming link plausible. (He has also said that if he was a policymaker, he would follow the conclusions of the IPCC report.)
Yes they have. James Hasen and Al Gore to name just two.
Well, I stand corrected on Hansen: I just read his AGU presentation from last week, where he does discuss this. As for Gore, I've never seen him make that argument. He has used Venus to illustrate the greenhouse effect, but I've never seen him claim that Earth is going to turn into Venus.
That is what this theory is all about and why they consider it dangerous to Humanity (they usually wheel out Venus as an example!).
No, that is not what this theory is all about. Virtually nobody in the literature talks about runaway greenhouse effects. The IPCC report doesn't claim this is going to happen. The usual economic policy responses are not based on the runaway greenhouse effect.
The actual forcing for Co2 in the atmosphere is logarithmic
This is true.
and cannot be greater than 1 - 1.5 degrees.
This is false. It's about 1 degree, unamplified, for 2xCO2, but larger for larger CO2 increases. "Logarithmic" doesn't mean "asymptotically constant".
The theory is entirely based on the possibility of secondary effects.
No, not entirely: there is the unamplified greenhouse effect which, contrary to your claim, does not saturate at 1-1.5 C. But you're right that feedbacks are a large part of the total effect. This is true for ANY source of warming, however, not just CO2. Those feedbacks are necessary to explain past natural changes as well as modern anthropogenic change.
I wonder if you are still confusing positive feedback with a runaway greenhouse.
Again, the paleo data supports CO2 lagging temperature.
In the case of the Pleistocene glacial-interglacial cycle, yes — there is no lag which is evident throughout paleo-history. But this d
Seasonal variability in ice cover does not somehow disprove global warming. You make the same mistake below with regard to the global temperature record.
There's no need. All I need do is show a graph of the global temperature anomaly.
The global temperature anomaly does not contradict the theory of CO2-based global warming. In fact, it is the primary set of evidence which supports it.
The argument is that man changes the Climate and has done since he started deforestation and agriculture.
Due to man's greenhouse gas emissions, as you will note. The same emissions which are now far greater than previously in the Holocene, as you may also note. Which neatly contradicts your claim that CO2-based warming is not supported by the evidence.
It's always amusing when skeptics contradict themselves in their rush to dig up anything they think contradicts mainstream science.
It's hard to argue with this as it's obvious.
It is not obvious, and in fact is strongly contested, even among those who believe that human greenhouse emissions are currently influencing the climate. It is far from clear how human CO2 and methane emissions from land use change and agriculture were large enough to stabilize the Holocene climate. If they were, this may indicate an even stronger greenhouse effect than is currently believed.
What's also obvious (and should be obvious to any intelligent person), is that when you are "against" warming or cooling, you're against it given the value you associate with the status-quo.
That's the point: a climate which changes too far or too quickly from the climate which societies are adapted to, in either direction (warming or cooling), will tend to incur economic damages.
It's clear that no run-away warming can take place, given the paleoclimate record:
No one has claimed that "run-away warming" (that is, warming which increases without bound) is going to take place. The claim is that some warming will take place. That claim is SUPPORTED by paleoclimate evidence; the same Phanerozoic record you cite implies a climate sensitivity similar to modern estimates. See, e.g., Royer et al. in Nature last year.
you can see that CO2 has been far, far higher in history than today, as have global temperature
Once again, that does not contradict the theory of CO2-induced greenhouse warming. The paleo data support that hypothesis.
It's called "winter". You may have heard of it. By the way, your link has nothing to do with ice sheets.
I don't know about you, but I think this whole theory of CO2 based Global Warming is looking a little threadbare right now.
You didn't cite any references which contradict the theory of CO2-based global warming, and you gave one link which supports it. It seems like you're starting with the conclusion you want to reach.
P.S. If you're so worried about forestalling the next ice age, you should be arguing that we save our excess fossil carbon for later when we really need it for climate control, instead of using it all up now when we don't.
Any regional effect you could produce would be a far different thing than the long term effects on the entire global system. You're making a lot of assumptions.
A regional test would precede a global test, obviously. You try it in stages, and if each stage works with no ill effects, you scale it up.
By the way, if you DID try this in the ocean, I can conceive of simple mechanical designs for buoys that would use wave energy to store and spray the water, but you would still need to make the buoys - think of the time, money and energy required
Duh, it costs money. So does reducing fossil fuel emissions. Geoengineering typically costs far less than abatement.
Basically, I'm against any scheme that doesn't address the runaway worldwide increase in fossil fuel use first-otherwise we are fighting the symptoms but not the source of the problem.
Your main point is valid, but the caveat is that we may end up needing to fight the symptoms if we don't successfully fight the source. As I said, I view geoengineering as a worst-case backup, not as the first line of defense.
Volcano eruptions reduce temperature by solid particulate, not aerosolized liquid - the definition of aerosol include both but it's two different things.
No, volcano eruptions primarily reduce temperature by aerosolized liquid, from SO2. Particulates also contribute, but not as much.
The global effects of the scheme in TFA cannot be studied unless tried on a global scale.
Again, duh. And again, that doesn't mean that we have to "bet the planet", or that geoengineering can't be safely tested.
First, that any effort to compensate for the global effects of greenhouse gas production is doomed to failure without first addressing the core issue of greenhouse gas production itself.
It's not "doomed to failure". It has side effects, but it's an open question whether those side effects are worse than the costs of dropping GHG production.
Second, that geoengineering schemes are intrinsically untestable
This is, as I noted, false: you can test them by implementing them. If they don't work or side effects start appearing, you stop.
How can you possibly "try it" in any valid, reproducible and meaningful way when the goal is reduction in mean global temperature?
Easy: you turn it on and see if the temperature goes down. The effect is fast and so should be quickly noticeable. You don't even have to start at a global scale; you can do it regionally.
Why not just attack it at the source rather than screw around with things we don't understand?
If by "attacking it at the source" you mean "reducing CO2 emissions", I agree that's the better plan. Unless we can't reduce them fast enough. I'm merely pointing out that geoengineering schemes are testable and we don't have to "bet the planet" on them.
Besides, where does the water come from
The ocean.
and where does the energy come from to power the sprays?
It can come from any energy source. If you're worried about the energy coming from fossil fuels, the real question is whether the temperature reduction is greater than the warming induced by extra fossil energy consumption. (The answer is likely yes, considering the amount of fossil fuels that had to be burned to raise current temperatures by less than 1 C.)
A completely unsupported assertion.
You cut off the part where I said "as far as temperature is concerned". And that is not completely unsupported. Aerosol geoengineering would certainly work to reduce temperatures, because volcanoes already do that. The current scheme discussed here is less well studied.
Unpredictable side effects? Are you SURE these would be better than the sea level rising?
No. I'm not in favor of geoengineering unless it's to prevent something really severe, like runaway melting of Greenland. I'm merely pointing out that geoengineering is feasible and it can be tested in a controlled manner, should anyone want to do it. I have not endorsed actually doing it.
TFA suggests using sea water. I don't know if it would cause massive rusting; I suspect the necessary quantity of water is small compared to the amount of seawater already evaporated. However, that's certainly an issue that would require further study if anyone wanted to go through with this plan.
Scientists can say the dumbest things sometimes. You want to stop global warming? QUIT CUTTING DOWN TREES!!!!!!!
If you were a scientist, you might know why that won't actually work. Halting deforestation won't stop global warming. Reforesting the entire planet won't stop global warming either. Our CO2 emissions are already far greater than the terrestrial carbon sink can take up (by a factor of about 4) and are still increasing. Reforesting won't increase the carbon sink by enough to stop global warming. It can slow it somewhat, however. But there are secondary effects: if you reforest in boreal regions, you can actually add to global warming, because the trees displace a lot of highly reflective (cooling) ground snow cover, and don't offset enough CO2 to outweigh the albedo shift.
Sulfates have a large direct effect from their albedo. They also have two indirect effects, on cloud formation and on cloud lifetimes. Reducing industrial sulfate emissions would indeed warm the planet; the existing emissions are thought to be already cooling the planet by a fairly substantial amount relative to the greenhouse effect. One geoengineering scheme is to inject more of them into the stratosphere ("artificial voclanoes"). It has a number of drawbacks due to potential side effects; Robock has a paper in which he lists 20 of them.
all current "efficient" energy production methods that is capable meeting the demand of this "invention" invariably increase greenhouse gases
The relevant question is not, does this scheme emit CO2? The relevant question is, does this scheme reduce temperatures more than the CO2 it emits raises them?
Clouds do form on dust though, water vapor condensing on it. You cant ignore this
This is true, but I'm sorry, the other poster is right. If you look at major volcanic cooling events like Pinatubo, by far the most visible effect on radiative transfer is from the aerosols. You can look at Robock's review article for some discussion.
You know, actual numbers and records. No models, no data from model, and no models of models are ever fact.
It's stupid to ignore everything we know about physics. Science consists of both theory and observation.
We agree; I'm far from convinced that it's a good idea myself. But I think it and other geoengineering schemes are worth investigating, as a worst-case backup solution in case we fail to reduce emissions enough.
I noticed that you said there are geoengineering schemes that would "almost certainly work", "almost" being the word that catches my eye. Are you that confident in the odds that you're willing to bet the planet?
As I noted in another response, we don't have to "bet the planet" in order to test geoengineering. We can do as little or as much of it as we want in order to study the effects, as long as we don't commit ourselves to doing it for a long period of time.
Yes, it has. That's why it's a real problem. Of course, we haven't seen nearly as much warming as we are likely to as CO2 emissions continue.
we are still at the tail end of the last ice age.
Going by the ice age cycle, we ought to be cooling by now. The modern warming has nothing to do with the ice age cycle.
Please, shed this idea of the noble unbiased scientist.
Please, shed the idea of incompetence and conspiracy. If you've got a scientific argument, present it. Dismissing arbitrary amounts of evidence on nothing more than allegations of bias is both fallacious and asinine.
I'll also note that many places to do not refer to it as Global Warming anymore because it turned out the average idiot forget about it every winter or even desired it. Now it's Climate Change 'cause we can say a freak blizzard is just as much climate change as a bad hurricane.
That's another retarded allegation of conspiracy. In reality, it was called "climate change" in the scientific literature long before "global warming" ever became popular.
Using real data to make a model does not mean the models are right.
You can't prove a model is right, you can only verify that it agrees with what we observe.
The problem is that models tend to be made to make the data fit the desired output.
Models are supposed to be constructed to reproduce observed climate behavior.
So here is simple question: If clouds cause global warming, why is it that cloudy days are always cooler days?
Clouds cause both warming and cooling, depending on the type and location of the cloud. Both observations and models find that, for cloud cover resulting from a warming planet, the warming effect dominates. As I said, this is uncertain, but "uncertain" doesn't mean "either possibility is equally likely".
You know this from your own experience, but we seem to ignore all this obvious data.
If you spent about 60 seconds with Google, you would realize that your knowledge of cloud-climate interactions is severely deficient. Here is one place you can start. Or you could, gasp, read a textbook or something.
I am very much concerned with humans destroying the ecosystem, and global warming is a very real threat. But, water is not whats going to kill us, it's what keeps it balanced so well.
All evidence says otherwise: water vapor serves as a positive climate feedback, not a negative one.
If water vapor and clouds could cause a runaway greenhouse effect, with such an abundance of water don't you think it would've happened in the last 4 billion years?
You are deeply confused.
"Positive feedback" does not mean "runaway feedback". That only happens when the gain is greater than unity. No one is claiming that water vapor is going to cause a runaway greenhouse effect, merely that it amplifies other radiative forcings.
Slashdot Mirror
Like it's the climate scientists who design and implement CO2 abatement policies? No, that's economists and politicians. Geoengineering is an ENGINEERING project. Scientists might tell engineers how much needs to happen, but they're not the ones who would design, build, or deploy the devices.
Besides, if you're insinuating that climate geoengineering is all a scientific conspiracy to get funding dollars, that's pretty lame. Even if you're a conspiracy nutjob, how is inventing a cheaper solution (geoengineering) than existing plans (emissions abatement) going to get them more money?
Because of the risk of side effects. Massively fertilizing ocean plankton, for instance, will undoubtedly have rather large effects on ocean ecosystems which all depend on plankton. It's rather questionable whether we can even fertilize the ocean enough to sequester most of the CO2 we'll put into the air over the next couple centuries; it only works insofar as iron continues to be the limiting nutrient. Once you dump tons in, it's no longer limiting. Likewise there are problems with other geoengineering schemes, such as aerosol geoengineering; the problem there is that the control (aerosols) operates on a very different timescale than the carbon cycle, so you have to guarantee that you can keep geoengineering going, uninterrupted, for centuries.
As for self referencing.. If you're legitimately advancing your previous work, why not?
There's nothing wrong with self referencing. But it shouldn't be used to quantify your paper's impact on the rest of the academic community. You can cite yourself all you want, for legitimate reasons, but that doesn't say anything about what impact your paper is having on anyone else.
Am I supposed to be impressed?
Sorry. I know John Baez personally, and "perceived wrongdoing against him" is the furthest from his motivations here.
I didn't say there weren't good reasons to self-cite. I said that self-citation shouldn't count as part of the impact factor, even if it's legitimate self-citation. A paper's impact should measure the paper's impact on OTHER researchers. If I'm the only one who cites my own paper, my citations may be for legitimate reasons (building on my previous work), but that doesn't mean I'm having an impact on the rest of the community.
I know what "endothermic" means. And you don't know what the hell you're talking about. We're not talking about cool mist wafting up from the surface due to circulation. We're talking about sudden transport to a cooler environment before the water droplets have time to cool or evaporate. Your ignorance of thermodynamics doesn't change the fact that water has been transported to a cooler environment, and not in a slow way that allows it to re-equilibrate before it gets there.
You may be interested to know that the blog's author invented the Crackpot Index.
Excluding references to the same journal is too harsh a criterion, since a lot of high quality papers get published in high quality journals. What should be perhaps excluded, though, is self-citation (whether to your own articles in the same or a different journal). Also, papers published in a journal by a journal editor shouldn't count.
The only way to 'inject' water into the atmosphere and have it radiate heat is to boil it.
Uh, no. You spray it at high velocity. If it reaches high altitudes before it has had time to cool, it will be warmer than its surroundings and will cool there. It will radiate its latent heat.
Yes, it is La Nina. It's true that the PDO is in its cool phase, as the JPL press release notes. It has been for some time now. That's not why 2008 is a cold year, relative to recent years. The reason why 2008 is a cold year relative to recent years is because most of this year was in or recovering from a La Nina. (And no, it's not a "record cold year" either. 2008 has been still quite warm, globally speaking, compared to most years in the 20th century.) The PDO cools the Pacific too, so the La Nina added on top of that. But the PDO doesn't explain why this year was cooler than recent years, because recent years were also in a PDO cool phase. The PDO influences the climatological background state, but the interannual temperatures are modulated by ENSO.
As I said, the PDO can influence the likelihood/magnitude of a La Nina, but if there's a big temperature difference between one year and the next, it's not fundamentally due to a multidecadal oscillation. Multidecadal oscillations don't have big changes from one year to the next.
Orbital/solar variations are far too weak/slow to explain the modern warming period. Nor is it explicable by surface heating from the oceans, as the oceans indicate that they are gaining heat, not losing it.
We are having a cold year because of La Nina (ENSO is not the PDO, although the PDO affects ENSO variability). ENSO is a large but transient phenomenon. There is no evidence that multi-decadal ocean or solar cycles have a larger influence on surface temperatures than greenhouse gases, given their abject failure to explain the observed temperature trends.
The water vapor is cooler than the surrounding areas.
No, it's not. It's warm surface water which is injected high into the cool atmosphere. It cools there and radiates heat. Some of that heat escapes to space.
How is this vapor going to be lofted to higher and cooler altitudes?
It's mechanically injected. That's the point of this proposal.
That graph shows long term trends. Look at the key.
You are deeply confused. The long-term trend in ice extent is strongly negative. A year with above-average winter ice extent does not disprove this trend.
Furthermore, what exactly is required to disprove this theory? Growing ice?
Not directly. Ice can grow in a warming world; it depends on the temperature-precipitation balance, winds, etc. This is particularly true of central contintental locations. However, a long term reversal in, say, sea ice melt would contradict warming polar temperatures. Of course, cooling polar temperatures would contradict warming polar temperatures: you don't need ice melt to measure that.
Reducing temperature?
A long term reduction in temperature (say, 20-30 years), in the presence of increasing CO2 and in the absence of other cooling factors like increased volcanic activity, would contradict the theory.
CO2 lagging temperature in the geological record?
No.
I don't think it does. Unless of course you attribute previous temperature rises to CO2, which you absolutely cannot.
The instrumental record of temperature rise through the 20th century absolutely can be attributed largely to CO2.
If you've read the Wegman report, or follow Steve McIntyre's blog
I do both.
(two people better versed in the mathematics of statistical analysis than any Climate Scientist),
You're hilarious.
you will see that they do not concur either.
You're still confused. They don't like the hockey stick. That doesn't mean that they disagree that CO2 causes warming. The Wegman Report didn't address that, and I remember Steve McIntyre noted on one of his comment threads last year that he finds the CO2-warming link plausible. (He has also said that if he was a policymaker, he would follow the conclusions of the IPCC report.)
Yes they have. James Hasen and Al Gore to name just two.
Well, I stand corrected on Hansen: I just read his AGU presentation from last week, where he does discuss this. As for Gore, I've never seen him make that argument. He has used Venus to illustrate the greenhouse effect, but I've never seen him claim that Earth is going to turn into Venus.
That is what this theory is all about and why they consider it dangerous to Humanity (they usually wheel out Venus as an example!).
No, that is not what this theory is all about. Virtually nobody in the literature talks about runaway greenhouse effects. The IPCC report doesn't claim this is going to happen. The usual economic policy responses are not based on the runaway greenhouse effect.
The actual forcing for Co2 in the atmosphere is logarithmic
This is true.
and cannot be greater than 1 - 1.5 degrees.
This is false. It's about 1 degree, unamplified, for 2xCO2, but larger for larger CO2 increases. "Logarithmic" doesn't mean "asymptotically constant".
The theory is entirely based on the possibility of secondary effects.
No, not entirely: there is the unamplified greenhouse effect which, contrary to your claim, does not saturate at 1-1.5 C. But you're right that feedbacks are a large part of the total effect. This is true for ANY source of warming, however, not just CO2. Those feedbacks are necessary to explain past natural changes as well as modern anthropogenic change.
I wonder if you are still confusing positive feedback with a runaway greenhouse.
Again, the paleo data supports CO2 lagging temperature.
In the case of the Pleistocene glacial-interglacial cycle, yes — there is no lag which is evident throughout paleo-history. But this d
Yes, I have. It's up 20%.
Seasonal variability in ice cover does not somehow disprove global warming. You make the same mistake below with regard to the global temperature record.
There's no need. All I need do is show a graph of the global temperature anomaly.
The global temperature anomaly does not contradict the theory of CO2-based global warming. In fact, it is the primary set of evidence which supports it.
The argument is that man changes the Climate and has done since he started deforestation and agriculture.
Due to man's greenhouse gas emissions, as you will note. The same emissions which are now far greater than previously in the Holocene, as you may also note. Which neatly contradicts your claim that CO2-based warming is not supported by the evidence.
It's always amusing when skeptics contradict themselves in their rush to dig up anything they think contradicts mainstream science.
It's hard to argue with this as it's obvious.
It is not obvious, and in fact is strongly contested, even among those who believe that human greenhouse emissions are currently influencing the climate. It is far from clear how human CO2 and methane emissions from land use change and agriculture were large enough to stabilize the Holocene climate. If they were, this may indicate an even stronger greenhouse effect than is currently believed.
What's also obvious (and should be obvious to any intelligent person), is that when you are "against" warming or cooling, you're against it given the value you associate with the status-quo.
That's the point: a climate which changes too far or too quickly from the climate which societies are adapted to, in either direction (warming or cooling), will tend to incur economic damages.
It's clear that no run-away warming can take place, given the paleoclimate record:
No one has claimed that "run-away warming" (that is, warming which increases without bound) is going to take place. The claim is that some warming will take place. That claim is SUPPORTED by paleoclimate evidence; the same Phanerozoic record you cite implies a climate sensitivity similar to modern estimates. See, e.g., Royer et al. in Nature last year.
you can see that CO2 has been far, far higher in history than today, as have global temperature
Once again, that does not contradict the theory of CO2-induced greenhouse warming. The paleo data support that hypothesis.
The ice-sheets are growing at the moment
It's called "winter". You may have heard of it. By the way, your link has nothing to do with ice sheets.
I don't know about you, but I think this whole theory of CO2 based Global Warming is looking a little threadbare right now.
You didn't cite any references which contradict the theory of CO2-based global warming, and you gave one link which supports it. It seems like you're starting with the conclusion you want to reach.
P.S. If you're so worried about forestalling the next ice age, you should be arguing that we save our excess fossil carbon for later when we really need it for climate control, instead of using it all up now when we don't.
Any regional effect you could produce would be a far different thing than the long term effects on the entire global system. You're making a lot of assumptions.
A regional test would precede a global test, obviously. You try it in stages, and if each stage works with no ill effects, you scale it up.
By the way, if you DID try this in the ocean, I can conceive of simple mechanical designs for buoys that would use wave energy to store and spray the water, but you would still need to make the buoys - think of the time, money and energy required
Duh, it costs money. So does reducing fossil fuel emissions. Geoengineering typically costs far less than abatement.
Basically, I'm against any scheme that doesn't address the runaway worldwide increase in fossil fuel use first-otherwise we are fighting the symptoms but not the source of the problem.
Your main point is valid, but the caveat is that we may end up needing to fight the symptoms if we don't successfully fight the source. As I said, I view geoengineering as a worst-case backup, not as the first line of defense.
Volcano eruptions reduce temperature by solid particulate, not aerosolized liquid - the definition of aerosol include both but it's two different things.
No, volcano eruptions primarily reduce temperature by aerosolized liquid, from SO2. Particulates also contribute, but not as much.
The global effects of the scheme in TFA cannot be studied unless tried on a global scale.
Again, duh. And again, that doesn't mean that we have to "bet the planet", or that geoengineering can't be safely tested.
First, that any effort to compensate for the global effects of greenhouse gas production is doomed to failure without first addressing the core issue of greenhouse gas production itself.
It's not "doomed to failure". It has side effects, but it's an open question whether those side effects are worse than the costs of dropping GHG production.
Second, that geoengineering schemes are intrinsically untestable
This is, as I noted, false: you can test them by implementing them. If they don't work or side effects start appearing, you stop.
How can you possibly "try it" in any valid, reproducible and meaningful way when the goal is reduction in mean global temperature?
Easy: you turn it on and see if the temperature goes down. The effect is fast and so should be quickly noticeable. You don't even have to start at a global scale; you can do it regionally.
Why not just attack it at the source rather than screw around with things we don't understand?
If by "attacking it at the source" you mean "reducing CO2 emissions", I agree that's the better plan. Unless we can't reduce them fast enough. I'm merely pointing out that geoengineering schemes are testable and we don't have to "bet the planet" on them.
Besides, where does the water come from
The ocean.
and where does the energy come from to power the sprays?
It can come from any energy source. If you're worried about the energy coming from fossil fuels, the real question is whether the temperature reduction is greater than the warming induced by extra fossil energy consumption. (The answer is likely yes, considering the amount of fossil fuels that had to be burned to raise current temperatures by less than 1 C.)
A completely unsupported assertion.
You cut off the part where I said "as far as temperature is concerned". And that is not completely unsupported. Aerosol geoengineering would certainly work to reduce temperatures, because volcanoes already do that. The current scheme discussed here is less well studied.
Unpredictable side effects? Are you SURE these would be better than the sea level rising?
No. I'm not in favor of geoengineering unless it's to prevent something really severe, like runaway melting of Greenland. I'm merely pointing out that geoengineering is feasible and it can be tested in a controlled manner, should anyone want to do it. I have not endorsed actually doing it.
TFA suggests using sea water. I don't know if it would cause massive rusting; I suspect the necessary quantity of water is small compared to the amount of seawater already evaporated. However, that's certainly an issue that would require further study if anyone wanted to go through with this plan.
Scientists can say the dumbest things sometimes. You want to stop global warming? QUIT CUTTING DOWN TREES!!!!!!!
If you were a scientist, you might know why that won't actually work. Halting deforestation won't stop global warming. Reforesting the entire planet won't stop global warming either. Our CO2 emissions are already far greater than the terrestrial carbon sink can take up (by a factor of about 4) and are still increasing. Reforesting won't increase the carbon sink by enough to stop global warming. It can slow it somewhat, however. But there are secondary effects: if you reforest in boreal regions, you can actually add to global warming, because the trees displace a lot of highly reflective (cooling) ground snow cover, and don't offset enough CO2 to outweigh the albedo shift.
Sulfates have a large direct effect from their albedo. They also have two indirect effects, on cloud formation and on cloud lifetimes. Reducing industrial sulfate emissions would indeed warm the planet; the existing emissions are thought to be already cooling the planet by a fairly substantial amount relative to the greenhouse effect. One geoengineering scheme is to inject more of them into the stratosphere ("artificial voclanoes"). It has a number of drawbacks due to potential side effects; Robock has a paper in which he lists 20 of them.
all current "efficient" energy production methods that is capable meeting the demand of this "invention" invariably increase greenhouse gases
The relevant question is not, does this scheme emit CO2? The relevant question is, does this scheme reduce temperatures more than the CO2 it emits raises them?
where's the water going to come from?
They propose to use sea water.
Clouds do form on dust though, water vapor condensing on it. You cant ignore this
This is true, but I'm sorry, the other poster is right. If you look at major volcanic cooling events like Pinatubo, by far the most visible effect on radiative transfer is from the aerosols. You can look at Robock's review article for some discussion.
You know, actual numbers and records. No models, no data from model, and no models of models are ever fact.
It's stupid to ignore everything we know about physics. Science consists of both theory and observation.
We agree; I'm far from convinced that it's a good idea myself. But I think it and other geoengineering schemes are worth investigating, as a worst-case backup solution in case we fail to reduce emissions enough.
I noticed that you said there are geoengineering schemes that would "almost certainly work", "almost" being the word that catches my eye. Are you that confident in the odds that you're willing to bet the planet?
As I noted in another response, we don't have to "bet the planet" in order to test geoengineering. We can do as little or as much of it as we want in order to study the effects, as long as we don't commit ourselves to doing it for a long period of time.
Global warming hasn't arrived,
Yes, it has. That's why it's a real problem. Of course, we haven't seen nearly as much warming as we are likely to as CO2 emissions continue.
we are still at the tail end of the last ice age.
Going by the ice age cycle, we ought to be cooling by now. The modern warming has nothing to do with the ice age cycle.
Please, shed this idea of the noble unbiased scientist.
Please, shed the idea of incompetence and conspiracy. If you've got a scientific argument, present it. Dismissing arbitrary amounts of evidence on nothing more than allegations of bias is both fallacious and asinine.
I'll also note that many places to do not refer to it as Global Warming anymore because it turned out the average idiot forget about it every winter or even desired it. Now it's Climate Change 'cause we can say a freak blizzard is just as much climate change as a bad hurricane.
That's another retarded allegation of conspiracy. In reality, it was called "climate change" in the scientific literature long before "global warming" ever became popular.
Using real data to make a model does not mean the models are right.
You can't prove a model is right, you can only verify that it agrees with what we observe.
The problem is that models tend to be made to make the data fit the desired output.
Models are supposed to be constructed to reproduce observed climate behavior.
So here is simple question: If clouds cause global warming, why is it that cloudy days are always cooler days?
Clouds cause both warming and cooling, depending on the type and location of the cloud. Both observations and models find that, for cloud cover resulting from a warming planet, the warming effect dominates. As I said, this is uncertain, but "uncertain" doesn't mean "either possibility is equally likely".
You know this from your own experience, but we seem to ignore all this obvious data.
If you spent about 60 seconds with Google, you would realize that your knowledge of cloud-climate interactions is severely deficient. Here is one place you can start. Or you could, gasp, read a textbook or something.
I am very much concerned with humans destroying the ecosystem, and global warming is a very real threat. But, water is not whats going to kill us, it's what keeps it balanced so well.
All evidence says otherwise: water vapor serves as a positive climate feedback, not a negative one.
If water vapor and clouds could cause a runaway greenhouse effect, with such an abundance of water don't you think it would've happened in the last 4 billion years?
You are deeply confused.
"Positive feedback" does not mean "runaway feedback". That only happens when the gain is greater than unity. No one is claiming that water vapor is going to cause a runaway greenhouse effect, merely that it amplifies other radiative forcings.