Yes. Generally if we consider something has positive externalities we tend to subsidize it.
Unless it happens to be fossil fuel production and usage. Then we tend to pretend positive externality doesn't exist.
Oh really. Now you are taking numbers out of your ass. If you think you are right, publish it. I am sure your methodology will be laugh at.
So what? We were looking for something comprehensive that covers the whole issue and was more accurate than the Stern report and other such reports. I found one such.
To the AC who missed this most important half of the gasoline "wealth redistribution program", you fail economics. To the moderator who modded Chas's post as "troll", get off my internet. This is a basic observation about the oil trade that everyone should acknowledge from the start.
It's more complex than that. Of course your willingness to pay for them will be $0. And let say they are willing to reduce their CO2 emission to close to 0 because they don't want their country to disappear. It won't be enough. Their sea level will still rise because of you. Does it mean they should pay the cost (losing their island) because you emit CO2? Seems unfair to me. You should pay for your own negative externalities, and not push them to other people or other generations.
Well, how much is an island worth? Again, I don't see anyone paying very much to protect these things. If it's not valuable to anyone else, then it's not valuable to me.
And if we're paying for our own externalities, shouldn't we also get compensated for our own externalities with the opposite sign?
Alright, where can I read these reports? I want something comprehensive that covers the whole issue. So don't give me a source that covers only a specific country/region or a specific consequence.
How about the Stern report where you take the estimated cost of global warming and divide it by ten. Then take the estimated cost of carbon dioxide emission reductions and multiply them by ten? That's a report that probably has more accurate cost/benefit analysis than the original report.
No, it is a better idea because it reduces highway deaths (in the US) without a significant increase in the cost of driving.
than the economic cost of excluding millions of people from driving
Many tens of millions of people are already banned from driving in the US due to age, driving history, or current state of impairment. What's known about the US situation is that a considerable fraction of accidents in the US come from drivers who are already banned from driving either by not having a license or insurance or by driving while impaired. Something like half of all US accidents involve people who shouldn't be driving at the time due to some combination of these factors.
while the probability of politicians banning a significant number of people from driving is about zero.
Here's a counterexample from Texas concerning uninsured drivers.
Of course. And the evidence shows that global warming is happening, and that human activity is responsible.
Partly responsible. Otherwise, I agree. So what? My argument hasn't been that AGW doesn't exist, but that there isn't compelling reason to act on it in a costly way.
We do. But how much do we value a pacific island nation that would disappear because of climate change? I mean not only the land but its people and culture. How much do we value species that would go extinct? That's not an answer for economists, it's a moral/political one. You can't answer that with science. Therefore you will never have scientific evidence that we should invest X$ to fight climate change, just like you will never have scientific evidence of the opposite. And this is not a valid reason for not doing anything.
What's your willingness to pay out of your own wealth to protect these things? That tells me exactly how valuable these things are. And that's how you transform any preference into a purely economic question.
So the best we have are reports such as the Stern, Garnaut, and IPCC reports. They all conclude we should lower our emissions.
Here's a propaganda lesson for you. These are first past the post arguments from authority. Just because they existed before most counterarguments were formulated. doesn't mean that they were the best arguments even at the time of their creation. For example, the Stern report's flawed time value factor was readily apparent, meaning that reinterpreting the study through a more appropriate time value is already at the time of the publishing of the Stern report, is already better than the Stern report was.
Huh, I've googled that phrase and have been told it's part of the "Summary for Policy Makers" for the IPCC Third Assessment Report (TAR). But when I actually look at the "Summary for Policy Makers", I see either the 0.2/decade increase for that scenario, baldly presented without error bars (see page 11 of the above link) or presented with far larger error bars (0.1 to 0.3 C/decade presented as 1C to 3+ C increase by end of century and the IS92a predicts near linear increase) than your statement suggests. So why do we have a graph with 0.1 to 0.3 C/decade and a written statement with 0.1 to 0.2 C/decade?
Also, let it be noted that IS92a scenario is not a scenario of the the TAR, but of a previous assessment report. Instead, the TAR presents its own scenarios depending on degree of adoption of non-fossil fuel energy technologies and global dependence on high tech industry. These scenarios uniformly predict a higher temperature increase per decade in the near future than IS92a does, even the scenarios that are more conservative in CO2 emissions.
Looks to me like someone took the boring prediction of 0.1 to 0.2 C per decade in the IS92a scenario and sexed it up to 0.1 to 0.3 C per decade for the graphs, forgetting to change the old written prediction. Here, we need more than merely being in line with inflated expectations. We also need someone who isn't consistently exaggerating the expectations.
There's some glaring abuse of charts as well. The chart on page 17, which claims that the effects of CO2 emissions will even in the face of substantial reductions in CO2 emissions from today will remain at elevated levels indefinitely even over the course of a 1,000 years. But there's nothing on the Y axis. It's touchie feelie curve drawing mixed with a huge assumption about how carbon sinking won't work.
You know, when I get told a story that just doesn't ring true, then I call people on it. And if you really want to be consistent, why don't you take your own advice?
There is no evidence in politics. And economics is a social science. Don't expect the same kind of evidence as in physics or biology.
These are non sequiturs. There is evidence in climatology. And economics is a science, should we choose to treat it as such.
So waiting to be 100% sure that global warming is happening can mean it will be too late (more expensive), and is just as stupid as waiting to be 100% sure the comet will it the earth.
I think there's a better chance of a good outcome waiting on a demonstration of the supposed dire nature of global warming. Keep in mind that there's plenty of evidence indicating that the effects of global warming are long in coming, slow to occur, and moderate in effect. It is near trivial for a human civilization to adapt under those circumstances. I don't see the compelling reason to act that a significant, likely asteroid impact would have.
If your circumstances prevent you from taking an opportunity that you would otherwise take, that is not a "choice".
Sure, it is, if they're willing to go through the effort. I don't buy at all the claim that one can't improve their circumstances. I can buy that they aren't sufficient interested in improving their circumstances to go through the effort.
I'm an IT guy. If I am looking for work, then I am looking for work in IT
That's moderately unconventional, actually. I doubt most IT people still work in IT. It's a tough field with tough work conditions which is not for most people.
Look at that. Seven categories of choices right there. You already figured it out.
To be clear, I have been gainfully employed for 25 years and have never had problems finding work or moving from one job to the next. But I am not so naive as to think that the right work is available to anyone who wants it at any time.
The "right work"? That sounds pretty naive to me right there. My view is merely that you can shop for a better job or merely a different job. Even if you're looking for a characteristic which can't completely go away (such as absence of stress or doing work as you feel like doing it), you still can look for work that is more suited to your desires.
Finally, my observation is based on the bald fact that the developed world, despite the problems it has created for employers, is still a pretty open market for workers. If your current job sucks a lot, you have ready means to look for better work.
So what? I tire of this fake helplessness. Sure, it matters to them how things seem. Sure, it matters that there are negative consequences to be overcome. But how much more of our societies can we afford to sacrifice to people who choose not to better their own lives?
That is a much bigger luxury then people often think.
It is a choice that anyone can make in the developed world.
If you mean I have the option of quitting my reasonably lucrative position in IT to go work for McDonald's, ok.
Yes, that is a choice. You can also start your own business or get IT work elsewhere. Now, if you really are so incompetent that you can't do any better than McDonalds as an alternate job, then your employer deserves your gratitude not your spite for giving you a job so much better than what you could find on your own.
I don't see any sign of that. China, for example, is a great supporter of the developed world cutting back at China's benefit. In fact, I think this particular game boils down to the developed world committing economic suicide while China builds up for its chance at being a superpower.
Keep in mind that such a level of freedom to reject work is an advantage a large percentage of Americans do not have.
Sure, they do. Just because there are mild, short term, negative consequences doesn't mean you don't have a choice. This whining reminds me of PvP games where people complain that someone who has played the game for a couple of years just so happens to be a better player than the person who signed up yesterday. So here's the usual advice given for delicate flowers: man up, L2P, and flush your victim card down the toilet.
You do realize companies often all but collude on this kind of thing?
'
And workers collude on what they want as well. Not really seeing the reason to care here. This temporary advantage of employers is due both to the considerable increase in supply of global labor over the past few decades and remarkably short-sighted labor policy in the developed world over that same period.
If we realize we were wrong it's easy to start emitting a lot of CO2 again. If we were right, and did nothing, it will be a lot more expensive.
Why would "we" ever realize we were wrong? The tiger-repelling rock worked.
The problem is that skepticism is not as seriously documented. Most simply deny global warming is happening, or that human activity has something to do with it (which is against the scientific consensus, we are no longer talking about economics and politics here). Where are the reports acknoleging AGW is happening, but that the costs of doing nothing is lower than the cost of acting against it? I haven't seen any.
Documentation != evidence. The fallacy of argument through obfuscation is just as much a fallacy as anything else.
With a given constant amount of CO2 emitted, do you agree that the temperature will be higher without polar ice than with polar ice? Water absorbs more heat than ice. Ice reflects more heat than ice. The fact that the hotter is the planet, the more heat radiate to space doesn't change that.
So what? We were speaking of positive and negative feedbacks. You pointed out a positive feedback given without context and I pointed out a negative feedback associated with the same system.
And I don't care that there is global warming. What I care about are the costs and benefits of the change.
As I said, we suppose we are 90% confident that this will happen. The OP said that we should never act before the science is settled. So in this case, applying this logic, we shouldn't do anything and hope for that 10%.
I grant that the perfectionism of the original poster is a bad idea, but that's just not the problem with global warming. There's considerable uncertainty greater than 10% that the cure is better than the disease, coupled with IMHO a considerable degree of bias towards presenting an argument for strong reductions in fossil fuel consumption.
For example, there's this bizarre insistence on only considering how to keep global warming under 2 C increase.
That's not going to happen unless both the degree of global warming is less than expected and humanity has a solid replacement for fossil fuels that decisively replaces them economically. Eg, renewables so much cheaper that they not only wipe out coal plants in electricity production, but also result in considerably cheaper electric vehicles than gas-powered vehicles. I think that is unlikely even if developed world countries start putting punitive taxes on carbon emissions. The rest of the world just isn't interested aside from relatively susceptible outliers like Bangladesh or the Micronesia countries.
There are criticisms about this report. But where is the report saying that global warming is happening, but that doing nothing will end up being cheaper than acting? There is none. Politics can never be 100% evidence based. See my example about the comet. We have to act according to what is the most likely with our current knowledge. Even if global warming was a hoax. Let say we reduce our CO2 emissions by 10%. City air quality will end up being cleaner.
Unless, it has a negative effect on air quality and city air quality turns out to be worse. The big problem with global warming remedies, is that they can increase global poverty. That tends to increase not decrease pollution.
And I disagree that things like the Stern Report are more within our current knowledge than the skepticism about these reports.
It's not enough. It's an equilibrium. If more ice melts, the earth temperature equilibrium shift to higher temperature. Of course radiation to space means that that positive feedback won't last forever. And anyway if all the ice melts the positive feedback will stop.
Sure, it is. As Earth shifts to higher temperatures, the amount of heat radiated to space increases as well.
There have been many, including the Stern Report. But at this point this is economics/politics, not climate science. Because to answer that question, we must answer questions such as what is the "worth" of a Pacific island nation. Assuming that this worth is > 0, then we should invest a non-zero amount of dollars into avoiding/mitigating/adapting to climate change.
Economics is a place where global warming predictions are egregiously wrong.
The Stern report in question overestimates future damage from global warming due to overly low time value (of money and other things) by using an artificially low economic growth rate value in place of the actual inflation-adjusted GDP growth (or similar measures of growth of economic value). For example, the cost of harms a century in advance were overstated by a factor of two.
And other costs are notoriously overestimated. A particularly big one is the alleged cost of sea level rise (coupled with alleged increases in storm strength). The typical approach is to look at the land that is predicted to be inundated (which often is highly priced) and value the cost of global warming as the destruction of that property. This ignores that most of that property will need to be replaced well before sea level rise becomes a factor in its destruction. And if you're going to do that, then a move to higher ground is not a significant additional cost.
Well, unless society chooses to make such activities overly expensive. For example, we could greatly reduce the alleged impact of sea level rise by reforming public flood insurance in the US. Not the world, the US. It's amazing how much of the supposed evidence for global warming, such as citing increased insurance claims for flooding and other extreme weather, relies on ignoring the effects of severely broken human systems. Another such example is the conflating of droughts caused by pumping out an aquifer with droughts caused by AGW.
Similar issues are uncovered with claims of loss of arable land. This ignores the increase in arable land coming from most of the heating occurring in the upper temperate zones of the Northern hemisphere.
How so? Global warming has a positive feedback. Warming melts polar ice, which in turns means less ice reflect solar heat into space, which means more warming of the earth.
And heat radiates into space as the fourth power of temperature. There's your global warming negative feedback.
Reports indicate that the earlier we start acting, the less costly it will be for mankind. Global warming isn't about the end of life on earth. It's about being poorer, globally. We will be poorer in 100 years if we do nothing, because warming will have a significant cost.
So what? Where's the evidence to back up those reports?
I pointed out that not everyone prejudges all ACs. They can't all be ignoring those really obvious problems.
Sure, they can. It's not a big stretch to say that the people who can better ignore the obvious problems are the same ones who better tolerate AC posting.
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Yes. Generally if we consider something has positive externalities we tend to subsidize it.
Unless it happens to be fossil fuel production and usage. Then we tend to pretend positive externality doesn't exist.
Oh really. Now you are taking numbers out of your ass. If you think you are right, publish it. I am sure your methodology will be laugh at.
So what? We were looking for something comprehensive that covers the whole issue and was more accurate than the Stern report and other such reports. I found one such.
Yeah. But with gasoline. You get...gasoline.
To the AC who missed this most important half of the gasoline "wealth redistribution program", you fail economics. To the moderator who modded Chas's post as "troll", get off my internet. This is a basic observation about the oil trade that everyone should acknowledge from the start.
And that's just where it sparks, if you could guess that the rise of Hitler would lead to the attack on Pearl Harbor your crystal ball is good.
The two weren't correlated so your crystal ball would be broken.
It's more complex than that. Of course your willingness to pay for them will be $0. And let say they are willing to reduce their CO2 emission to close to 0 because they don't want their country to disappear. It won't be enough. Their sea level will still rise because of you. Does it mean they should pay the cost (losing their island) because you emit CO2? Seems unfair to me. You should pay for your own negative externalities, and not push them to other people or other generations.
Well, how much is an island worth? Again, I don't see anyone paying very much to protect these things. If it's not valuable to anyone else, then it's not valuable to me.
And if we're paying for our own externalities, shouldn't we also get compensated for our own externalities with the opposite sign?
Alright, where can I read these reports? I want something comprehensive that covers the whole issue. So don't give me a source that covers only a specific country/region or a specific consequence.
How about the Stern report where you take the estimated cost of global warming and divide it by ten. Then take the estimated cost of carbon dioxide emission reductions and multiply them by ten? That's a report that probably has more accurate cost/benefit analysis than the original report.
That is not a better idea, just a different idea.
No, it is a better idea because it reduces highway deaths (in the US) without a significant increase in the cost of driving.
than the economic cost of excluding millions of people from driving
Many tens of millions of people are already banned from driving in the US due to age, driving history, or current state of impairment. What's known about the US situation is that a considerable fraction of accidents in the US come from drivers who are already banned from driving either by not having a license or insurance or by driving while impaired. Something like half of all US accidents involve people who shouldn't be driving at the time due to some combination of these factors.
while the probability of politicians banning a significant number of people from driving is about zero.
Here's a counterexample from Texas concerning uninsured drivers.
Of course. And the evidence shows that global warming is happening, and that human activity is responsible.
Partly responsible. Otherwise, I agree. So what? My argument hasn't been that AGW doesn't exist, but that there isn't compelling reason to act on it in a costly way.
We do. But how much do we value a pacific island nation that would disappear because of climate change? I mean not only the land but its people and culture. How much do we value species that would go extinct? That's not an answer for economists, it's a moral/political one. You can't answer that with science. Therefore you will never have scientific evidence that we should invest X$ to fight climate change, just like you will never have scientific evidence of the opposite. And this is not a valid reason for not doing anything.
What's your willingness to pay out of your own wealth to protect these things? That tells me exactly how valuable these things are. And that's how you transform any preference into a purely economic question.
So the best we have are reports such as the Stern, Garnaut, and IPCC reports. They all conclude we should lower our emissions.
Here's a propaganda lesson for you. These are first past the post arguments from authority. Just because they existed before most counterarguments were formulated. doesn't mean that they were the best arguments even at the time of their creation. For example, the Stern report's flawed time value factor was readily apparent, meaning that reinterpreting the study through a more appropriate time value is already at the time of the publishing of the Stern report, is already better than the Stern report was.
Huh, I've googled that phrase and have been told it's part of the "Summary for Policy Makers" for the IPCC Third Assessment Report (TAR). But when I actually look at the "Summary for Policy Makers", I see either the 0.2/decade increase for that scenario, baldly presented without error bars (see page 11 of the above link) or presented with far larger error bars (0.1 to 0.3 C/decade presented as 1C to 3+ C increase by end of century and the IS92a predicts near linear increase) than your statement suggests. So why do we have a graph with 0.1 to 0.3 C/decade and a written statement with 0.1 to 0.2 C/decade?
Also, let it be noted that IS92a scenario is not a scenario of the the TAR, but of a previous assessment report. Instead, the TAR presents its own scenarios depending on degree of adoption of non-fossil fuel energy technologies and global dependence on high tech industry. These scenarios uniformly predict a higher temperature increase per decade in the near future than IS92a does, even the scenarios that are more conservative in CO2 emissions.
Looks to me like someone took the boring prediction of 0.1 to 0.2 C per decade in the IS92a scenario and sexed it up to 0.1 to 0.3 C per decade for the graphs, forgetting to change the old written prediction. Here, we need more than merely being in line with inflated expectations. We also need someone who isn't consistently exaggerating the expectations.
There's some glaring abuse of charts as well. The chart on page 17, which claims that the effects of CO2 emissions will even in the face of substantial reductions in CO2 emissions from today will remain at elevated levels indefinitely even over the course of a 1,000 years. But there's nothing on the Y axis. It's touchie feelie curve drawing mixed with a huge assumption about how carbon sinking won't work.
You know, when I get told a story that just doesn't ring true, then I call people on it. And if you really want to be consistent, why don't you take your own advice?
There is no evidence in politics. And economics is a social science. Don't expect the same kind of evidence as in physics or biology.
These are non sequiturs. There is evidence in climatology. And economics is a science, should we choose to treat it as such.
So waiting to be 100% sure that global warming is happening can mean it will be too late (more expensive), and is just as stupid as waiting to be 100% sure the comet will it the earth.
I think there's a better chance of a good outcome waiting on a demonstration of the supposed dire nature of global warming. Keep in mind that there's plenty of evidence indicating that the effects of global warming are long in coming, slow to occur, and moderate in effect. It is near trivial for a human civilization to adapt under those circumstances. I don't see the compelling reason to act that a significant, likely asteroid impact would have.
If your circumstances prevent you from taking an opportunity that you would otherwise take, that is not a "choice".
Sure, it is, if they're willing to go through the effort. I don't buy at all the claim that one can't improve their circumstances. I can buy that they aren't sufficient interested in improving their circumstances to go through the effort.
I'm an IT guy. If I am looking for work, then I am looking for work in IT
That's moderately unconventional, actually. I doubt most IT people still work in IT. It's a tough field with tough work conditions which is not for most people.
To be clear, I have been gainfully employed for 25 years and have never had problems finding work or moving from one job to the next. But I am not so naive as to think that the right work is available to anyone who wants it at any time.
The "right work"? That sounds pretty naive to me right there. My view is merely that you can shop for a better job or merely a different job. Even if you're looking for a characteristic which can't completely go away (such as absence of stress or doing work as you feel like doing it), you still can look for work that is more suited to your desires.
Finally, my observation is based on the bald fact that the developed world, despite the problems it has created for employers, is still a pretty open market for workers. If your current job sucks a lot, you have ready means to look for better work.
or a lot of people it is not
So what? I tire of this fake helplessness. Sure, it matters to them how things seem. Sure, it matters that there are negative consequences to be overcome. But how much more of our societies can we afford to sacrifice to people who choose not to better their own lives?
That is a much bigger luxury then people often think.
It is a choice that anyone can make in the developed world.
If you mean I have the option of quitting my reasonably lucrative position in IT to go work for McDonald's, ok.
Yes, that is a choice. You can also start your own business or get IT work elsewhere. Now, if you really are so incompetent that you can't do any better than McDonalds as an alternate job, then your employer deserves your gratitude not your spite for giving you a job so much better than what you could find on your own.
I don't see any sign of that. China, for example, is a great supporter of the developed world cutting back at China's benefit. In fact, I think this particular game boils down to the developed world committing economic suicide while China builds up for its chance at being a superpower.
Keep in mind that such a level of freedom to reject work is an advantage a large percentage of Americans do not have.
Sure, they do. Just because there are mild, short term, negative consequences doesn't mean you don't have a choice. This whining reminds me of PvP games where people complain that someone who has played the game for a couple of years just so happens to be a better player than the person who signed up yesterday. So here's the usual advice given for delicate flowers: man up, L2P, and flush your victim card down the toilet.
You do realize companies often all but collude on this kind of thing?
' And workers collude on what they want as well. Not really seeing the reason to care here. This temporary advantage of employers is due both to the considerable increase in supply of global labor over the past few decades and remarkably short-sighted labor policy in the developed world over that same period.
Because not everyone has the option of simply "working somewhere else".
Sure, if you're a slave in Sudan. In the developed world, everyone does have the option of working somewhere else.
It is part of the social contract you make with the rest of humanity.
Put it on paper, then we'll discuss whether to accept it or not as a contract with the rest of society.
So it looks like we are right in line with expectations.
Only because those expectations are low over the near future.
The rest of the world is interested, as long as the developped world, who contributed the most to global warming, lead the way.
In other words, as long as somebody else does the actual work? That doesn't sound like interest to me.
If we realize we were wrong it's easy to start emitting a lot of CO2 again. If we were right, and did nothing, it will be a lot more expensive.
Why would "we" ever realize we were wrong? The tiger-repelling rock worked.
The problem is that skepticism is not as seriously documented. Most simply deny global warming is happening, or that human activity has something to do with it (which is against the scientific consensus, we are no longer talking about economics and politics here). Where are the reports acknoleging AGW is happening, but that the costs of doing nothing is lower than the cost of acting against it? I haven't seen any.
Documentation != evidence. The fallacy of argument through obfuscation is just as much a fallacy as anything else.
With a given constant amount of CO2 emitted, do you agree that the temperature will be higher without polar ice than with polar ice? Water absorbs more heat than ice. Ice reflects more heat than ice. The fact that the hotter is the planet, the more heat radiate to space doesn't change that.
So what? We were speaking of positive and negative feedbacks. You pointed out a positive feedback given without context and I pointed out a negative feedback associated with the same system.
And I don't care that there is global warming. What I care about are the costs and benefits of the change.
As I said, we suppose we are 90% confident that this will happen. The OP said that we should never act before the science is settled. So in this case, applying this logic, we shouldn't do anything and hope for that 10%.
I grant that the perfectionism of the original poster is a bad idea, but that's just not the problem with global warming. There's considerable uncertainty greater than 10% that the cure is better than the disease, coupled with IMHO a considerable degree of bias towards presenting an argument for strong reductions in fossil fuel consumption.
For example, there's this bizarre insistence on only considering how to keep global warming under 2 C increase.
That's not going to happen unless both the degree of global warming is less than expected and humanity has a solid replacement for fossil fuels that decisively replaces them economically. Eg, renewables so much cheaper that they not only wipe out coal plants in electricity production, but also result in considerably cheaper electric vehicles than gas-powered vehicles. I think that is unlikely even if developed world countries start putting punitive taxes on carbon emissions. The rest of the world just isn't interested aside from relatively susceptible outliers like Bangladesh or the Micronesia countries.
There are criticisms about this report. But where is the report saying that global warming is happening, but that doing nothing will end up being cheaper than acting? There is none. Politics can never be 100% evidence based. See my example about the comet. We have to act according to what is the most likely with our current knowledge. Even if global warming was a hoax. Let say we reduce our CO2 emissions by 10%. City air quality will end up being cleaner.
Unless, it has a negative effect on air quality and city air quality turns out to be worse. The big problem with global warming remedies, is that they can increase global poverty. That tends to increase not decrease pollution.
And I disagree that things like the Stern Report are more within our current knowledge than the skepticism about these reports.
It's not enough. It's an equilibrium. If more ice melts, the earth temperature equilibrium shift to higher temperature. Of course radiation to space means that that positive feedback won't last forever. And anyway if all the ice melts the positive feedback will stop.
Sure, it is. As Earth shifts to higher temperatures, the amount of heat radiated to space increases as well.
Big enough to kill thousands of people.
Unless, of course, it's not that big.
There have been many, including the Stern Report. But at this point this is economics/politics, not climate science. Because to answer that question, we must answer questions such as what is the "worth" of a Pacific island nation. Assuming that this worth is > 0, then we should invest a non-zero amount of dollars into avoiding/mitigating/adapting to climate change.
Economics is a place where global warming predictions are egregiously wrong.
The Stern report in question overestimates future damage from global warming due to overly low time value (of money and other things) by using an artificially low economic growth rate value in place of the actual inflation-adjusted GDP growth (or similar measures of growth of economic value). For example, the cost of harms a century in advance were overstated by a factor of two.
And other costs are notoriously overestimated. A particularly big one is the alleged cost of sea level rise (coupled with alleged increases in storm strength). The typical approach is to look at the land that is predicted to be inundated (which often is highly priced) and value the cost of global warming as the destruction of that property. This ignores that most of that property will need to be replaced well before sea level rise becomes a factor in its destruction. And if you're going to do that, then a move to higher ground is not a significant additional cost.
Well, unless society chooses to make such activities overly expensive. For example, we could greatly reduce the alleged impact of sea level rise by reforming public flood insurance in the US. Not the world, the US. It's amazing how much of the supposed evidence for global warming, such as citing increased insurance claims for flooding and other extreme weather, relies on ignoring the effects of severely broken human systems. Another such example is the conflating of droughts caused by pumping out an aquifer with droughts caused by AGW.
Similar issues are uncovered with claims of loss of arable land. This ignores the increase in arable land coming from most of the heating occurring in the upper temperate zones of the Northern hemisphere.
How so? Global warming has a positive feedback. Warming melts polar ice, which in turns means less ice reflect solar heat into space, which means more warming of the earth.
And heat radiates into space as the fourth power of temperature. There's your global warming negative feedback.
Reports indicate that the earlier we start acting, the less costly it will be for mankind. Global warming isn't about the end of life on earth. It's about being poorer, globally. We will be poorer in 100 years if we do nothing, because warming will have a significant cost.
So what? Where's the evidence to back up those reports?
I pointed out that not everyone prejudges all ACs. They can't all be ignoring those really obvious problems.
Sure, they can. It's not a big stretch to say that the people who can better ignore the obvious problems are the same ones who better tolerate AC posting.