The Planetary Emergency

[luiz]

With all the respect I generally have for you, you really come across as a dick here.

It's hard not to be!

We have people like the climatologist in the OP behaving like some biblical prophet aware of mystical truths beyond the reach of us mere mortals. We're asked by him and those like him to give up our entire way of life, to make an unprecedented effort on a global scale that would require a monstrous sacrifice from people already living in poverty to fight this menace that neither him nor anyone else understands at all. I insist, it's impossible to quantify the net gains and losses the warming will cause. It's even more ridiculous to suggest that a rise in average temperatures will lead necessarily to more draughts, more floods, more disasters. Why can't it lead to less? The belief that the temperature of the pre-industrial revolution period is some sort of absolute optimum is like a religious dogma; it has nothing supporting it. A curious fact is that before the present Global Warming hysteria many people (notably John von Neumann) believed that a warmer Earth would lead to more prospertity, and even suggested ways to artificially increase global temperatures (not saying they were right, but they weren't any wronger either). At most we'll have to adapt our existing infra-structure.

What's more, this climatologist knows full well that we won't cut carbon emmissions anywhere near the extent or speed they claim is necessary to avoid catastrophe. So why aren't we seeing more focus on how to cope with a warmer world instead of this hysteria over a solution that won't happen? Are we to believe that mankind will be unable to cope? That a 4 degrees increase in global average temperature (which may or may not happen) will drive us to the caves? Why is nobody talking of large scale engineering solutions to cope with a warmer world, instead of this endless doomsday preaching by climatologists?

Finally, we ought to be annoyed by his attitude because there are much bigger problems out there. The enormous gains of third world industrialization far outweight the supposed losses of warming. The hundreds of millions of people without access to electricity, to sewer systems, to even the smallest modern comfort couldn't care less about this "planetary emergency", nor they should.

 

[luiz]

A planetary emergency just means that it's going to be a bumpy ride for the next decade or so while we are still trying to get our act together.

You believe we'll see significant effects in the next decade?

 

[Murky]

You believe we'll see significant effects in the next decade?

We're already seeing significant effects. The 2012 drought has been attributed to the slowing of the Jet Stream that created a blocking effect. That just means that bad weather stays in one place longer as with the extremely hot and dry conditions.

There's a good blog post on the expected outcome on ScientificAmerican.com

On September 19th, NSIDC, the National Snow and Ice Data Center, announced that Arctic sea ice has shrunk as far as it will shrink this summer, and that the ice is beginning to reform, expanding the floating ice cap that covers the North Pole and the seas around it. The Arctic Sea Ice extent this September was far smaller than the previous record set in 2007. At 3.4 million square kilometers of ice coverage, this year’s Arctic minimum was 600,000 square kilometers smaller than the 2007 record. That difference between the previous record and this year’s is larger than the entire state of California, and almost as large as the state of Texas. An ice-free summer in the Arctic, once projected to be more than a century away, now looks possible decades from now. Some say that it looks likely in just the next few years.

What’s happening in the Arctic? Why is it happening? And does it matter for the bulk of us who live thousands of miles away from it?

http://blogs.scientificamerican.com/guest-blog/2012/09/21/arctic-sea-ice-what-why-and-what-next/

 

[tokala]

The belief that the temperature of the pre-industrial revolution period is some sort of absolute optimum is like a religious dogma; it has nothing supporting it.

It has literally everything to support it.

You answer this yourself:

At most we'll have to adapt our existing infra-structure.

On a permanent base.

It is the climate in which modern industrial civilization and agriculture was developed, is adapted to and optimized for.

It might very well be that if modern civilization would have been arisen in a stable climate a bit warmer than today, it would have developed better than in the real world case.

But that's not the alternative we will have.
The alternative will be a permanently changing climate, changing much faster than anytime since the rise of agriculture.
A new stable climate condition will not be reached until several decades after greenhouse gas levels have been stabilized.

And a lot of people are thinking about geoengineering solutions, problem is, none of those are easy, cheap or without side effects that might be even worse than the original problem.

 

[illram]

Even a small rise in sea levels would impact a significant number of people, poor and wealthy alike, since so much of the Earth's population lives near the coast or in low lying areas. A 6 foot (2m) rise would have a significant impact on the San Francisco Bay Area, for instance, and would flood a lot of the Sacramento Valley, which has a lot of people and agriculture and is a breadbasket for the United States, not to mention the disruption of fresh water that farmers in southern parts of the State depend on from the Sacramento river delta.

Whether people disagree on it being a "catastrophe" it seems foolish to simply dismiss it and not think about solutions or consequences at all. And I agree those solutions should also include contingency plans on how to cope with the inevitable reality that humans will not significantly change their consumption and energy usage and we will need to simply learn how to deal with these possible changes. And if we don't do anything and there is a sea level rise, one of the things we will need to deal with is the displacement of large numbers of people and the disruption in food supplies, and the inevitable conflicts that will likely flow from these events. These problems will disproportionately affect poorer parts of the world, so this is not a highfalutin' western elitist thing at all.

 

[History_Buff]

I only disregard their best guesses when they portray them as something more than exactly that, a best guess. The arrogant scientists on the OP are essentially warning us of an incoming apocalypse, which is absurd and illogical.

That's just pointless semantics though. Best guess here means more than me or you guessing. It's his bloody job, and he has evidence to back it up. Nobody is saying it's going to be an apocalypse, and all you're doing is inventing a strawman.

But we don't know that at all!

The real behavior of ice sheets have constantly proven the models wrong. Some are melting way faster than the models predicted, other aren't melting at all (or even expanding) despite the fact that they "should" be melting.

Again, neither he nor anyone else knows that. While there is an undeniable long term trend of warming, the extent of this warming and how it develops over time is not understood and has proven all models wrong. For instance, which model predicted that the last years would see no increase in global average temperature? (not saying this proves global warming stopped or anything, just saying it proves how little we know of it and how ridiculous people who pretend to have it all figured out sound).

The time frame I was asking about is the frame personally relevant to you.

As for Ice vs. Models, they have not proven the models wrong. In your second paragraph, you make the exact same mistake: thinking that a model designed to model climate over a decade or more can reliably predict year over year changes.

No, we don't have a complete picture of the climate. Not even close. And yet every piece of evidence we have says the Earth is warming, quickly, and its our fault. Ice is melting faster than it should be, seas are rising. And yet you are saying 'we don't have a complete picture, better just do nothing'. It's complete idiocy.

 

[luiz]

It has literally everything to support it.

You answer this yourself:

On a permanent base.

It is the climate in which modern industrial civilization and agriculture was developed, is adapted to and optimized for.

It might very well be that if modern civilization would have been arisen in a stable climate a bit warmer than today, it would have developed better than in the real world case.

But that's not the alternative we will have.
The alternative will be a permanently changing climate, changing much faster than anytime since the rise of agriculture.
A new stable climate condition will not be reached until several decades after greenhouse gas levels have been stabilized.

And a lot of people are thinking about geoengineering solutions, problem is, none of those are easy, cheap or without side effects that might be even worse than the original problem.

My issue is more with the insistence that a warmer weather will lead to more draughts, floods, and other assorted catastrophes. I see no reason why the balance of increase and decrase in abnormal events can't be zero. There was nothing sacred about our previous average temperature (which was constantly changing anyway).

As for infra-structure, obviously there'll be issues. But it's not like we would lose everything; power plants and steel mills won't shut donwn because of it. It's noteworthy to remember the opposite effects; in some regions we will spend more on air conditioning while other will save on heating.

As for permanent changing temperature, I'm not sure. Carbon emmissions seem to follow an U-shaped curve (though the descending part is relatively flat), much like say steel consumption. On the early phases of industrialization it rises really fast, then slower, and then stabilizes and start to slowly fall. At least that's what I gather from Europe and the US. China, India and Africa will probably follow a similar pattern, which means that we probably still have a few decades of growing emmissions, but that won't last forever.

 

[luiz]

That's just pointless semantics though. Best guess here means more than me or you guessing. It's his bloody job, and he has evidence to back it up. Nobody is saying it's going to be an apocalypse, and all you're doing is inventing a strawman.

Well, let me list all the blatantly unscientific stuff in the OP article:

"Environmentalists warn that a string of recent extreme weather events around the globe, including deadly typhoons, devastating floods and severe droughts, show urgent action on emission cuts is needed.

The extreme weather include the drought and heat waves that struck the United States in the summer."

Complete nonsense as nobody can link any of those events, or even all of them collectively, to global warming.

"One consequence of the melt is the slow but continuous rise in the ocean level that threatens coastal areas."

Just to be clear, the article is about the melting Artic ice caps. But that doesn't raise ocean levels at all, as they are ocean water floating, much like a rock of ice melting in a soda glass does not raise overall level. The melt of ice trapped on land would raise sea levels, but those are much harder to melt and the article is not about them.

"The implications are enormous and also mysterious," said environmentalist Bill McKibben, co-founder of 350.org, a global non-governmental organization focused on solving the climate crisis."

Enormous and mysterious.

As for Ice vs. Models, they have not proven the models wrong. In your second paragraph, you make the exact same mistake: thinking that a model designed to model climate over a decade or more can reliably predict year over year changes.

No, we don't have a complete picture of the climate. Not even close. And yet every piece of evidence we have says the Earth is warming, quickly, and its our fault. Ice is melting faster than it should be, seas are rising. And yet you are saying 'we don't have a complete picture, better just do nothing'. It's complete idiocy.

I wouldn't say do nothing. I would say not to present apocalyptical scenarios without evidence. I would say to focus on graver more present problems already affecting hundreds of millions. I would say to not repeat hysterically a solution that simply won't happen (drastic and immediate reduction in greenhouse emmissions), and instead devote all that energy and money into finding ways of coping with reality.

 

[tokala]

My issue is more with the insistence that a warmer weather will lead to more draughts, floods, and other assorted catastrophes. I see no reason why the balance of increase and decrase in abnormal events can't be zero. There was nothing sacred about our previous average temperature (which was constantly changing anyway).

Once again, the "old" state is what we are used to.
It is, by definition, normal. Nothing inherently special.
Now turn up the heat.
Temperatures for a given location follows roughly a gaussian normal distribution (bell shape), a higher average temperature means that curve moves to higher temperatures (image from a recent Hansen paper):

"Extreme heat" as defined under the old regime (reference period) could be considered anything above 3 sigma, occuring very rarely (<1% of the time).
Now that bell curve is moving up, with what used to be a rare heat wave becoming much, much more frequent, and heat extremes unheard of under the old regime (5 sigma) becoming about as frequent as the old "extreme heat" (which is now a regular occurence).
As water vapor content of the atmosphere rises with temperature, precipitation is expected to follow a similar pattern.

Think of it as "once every century" events becoming "one every decade" events. And that's for now, things will get progressively nastier with average temperatures rising further.

Of course that's a bit simplified, but for more details one would need to really get into the primary literature.

As for infra-structure, obviously there'll be issues. But it's not like we would lose everything; power plants and steel mills won't shut donwn because of it.

Actually power plants are threatened by shutdowns due to low and warm river water in the summer.

It's noteworthy to remember the opposite effects; in some regions we will spend more on air conditioning while other will save on heating.

If you look at where most of the population of the "Industrialized World" is located, you will find that it is in the southern part of the northern temperate zone, and the adjacent subtropic regions, i.e. increased AC requirements will dominate.

As for permanent changing temperature, I'm not sure. Carbon emmissions seem to follow an U-shaped curve (though the descending part is relatively flat), much like say steel consumption. On the early phases of industrialization it rises really fast, then slower, and then stabilizes and start to slowly fall. At least that's what I gather from Europe and the US. China, India and Africa will probably follow a similar pattern, which means that we probably still have a few decades of growing emmissions, but that won't last forever.

Not forever, but assuming business as usual, and ChIndia catching up to OECD greenhouse gas emission levels per capita would mean temperatures rising for a century or two, with at least 0.2°C per decade, and very likely faster.
For our lifetimes, this equals "permanently".

 

[tokala]

Complete nonsense as nobody can link any of those events, or even all of them collectively, to global warming.

In fact, the Hansen paper I took that figure out of does exactly that, and fairly convincingly at that.

Just to be clear, the article is about the melting Artic ice caps. But that doesn't raise ocean levels at all, as they are ocean water floating, much like a rock of ice melting in a soda glass does not raise overall level. The melt of ice trapped on land would raise sea levels, but those are much harder to melt and the article is not about them.

No, but Arctic summer sea ice area getting progressively smaller means
a) more sunlight absorbed
b) more water vapor over the arctic ocean
That process acts as a positive feeback to arctic temperature rise, which already is the region of the globe with the largest temperature increase.
And this will very likely accelerate the loss rate of the Greenland ice cap.

 

[TheLastOne36]

I wouldn't say do nothing. I would say not to present apocalyptical scenarios without evidence. I would say to focus on graver more present problems already affecting hundreds of millions. I would say to not repeat hysterically a solution that simply won't happen (drastic and immediate reduction in greenhouse emmissions), and instead devote all that energy and money into finding ways of coping with reality.

Global Warming can be bullcrap for all that it matters, but we do need to seriously cut down on greenhouse emissions as those emissions do go into the atmosphere and they do come back down into our oceans raising ocean acidity levels.

Even a small rise in ocean acidity levels can cause extinction of lots of ocean life and ecosystems.

I'm no scientist so here is a video explaining this if you have the time. Link

 

[History_Buff]

My issue is more with the insistence that a warmer weather will lead to more draughts, floods, and other assorted catastrophes. I see no reason why the balance of increase and decrase in abnormal events can't be zero. There was nothing sacred about our previous average temperature (which was constantly changing anyway).

It won't balance out, because that's not how physics works. A warmer world means more energy in the atmosphere, which means more violent and unpredictable weather. It doesn't just balance out evenly such that daily highs and lows increase by X degrees.

Well, let me list all the blatantly unscientific stuff in the OP article:

"Environmentalists warn that a string of recent extreme weather events around the globe, including deadly typhoons, devastating floods and severe droughts, show urgent action on emission cuts is needed.

The extreme weather include the drought and heat waves that struck the United States in the summer."

Complete nonsense as nobody can link any of those events, or even all of them collectively, to global warming.

See Tokala's chart. You absolutely can link them. It's not even very difficult.

"One consequence of the melt is the slow but continuous rise in the ocean level that threatens coastal areas."

Just to be clear, the article is about the melting Artic ice caps. But that doesn't raise ocean levels at all, as they are ocean water floating, much like a rock of ice melting in a soda glass does not raise overall level. The melt of ice trapped on land would raise sea levels, but those are much harder to melt and the article is not about them.

Oh, I'm well aware that the melting of the Arctic ice caps won't actually raise sea levels. I think it actually slightly lowers them, since the floating ice winds up displacing more water that it does melted.

But the fact that that statement has been oversimplified doesn't change the fact that he's right. Melting ice caps means lower albedo, more dark oceans, more ocean warming, and corresponding thermal expansion. The melting ice is also symptomatic of the larger problem; even if the melting ice didn't alter the planetary albedo, the thermal expansion of the oceans would still raise sea levels.

"The implications are enormous and also mysterious," said environmentalist Bill McKibben, co-founder of 350.org, a global non-governmental organization focused on solving the climate crisis."

Enormous and mysterious.

That is a perfectly true statement.

I wouldn't say do nothing. I would say not to present apocalyptical scenarios without evidence. I would say to focus on graver more present problems already affecting hundreds of millions. I would say to not repeat hysterically a solution that simply won't happen (drastic and immediate reduction in greenhouse emmissions), and instead devote all that energy and money into finding ways of coping with reality.

Nobody is being hysterical about anything. You're just harping on the same bloody strawman. We need to make drastic emissions cuts. We also need to address those other problems at the same time; and I would also object to calling them greater, but since I don't know what you're specifically talking about, I won't.

As for the alternate course you've presenting in the last few words there, that is an option. But all of the estimates we've done suggest that it's cheaper to make cuts now than it is to keep on trucking, and then cope with a warmer world.

 

[luiz]

Once again, the "old" state is what we are used to.
It is, by definition, normal. Nothing inherently special.
Now turn up the heat.
Temperatures for a given location follows roughly a gaussian normal distribution (bell shape), a higher average temperature means that curve moves to higher temperatures (image from a recent Hansen paper):

"Extreme heat" as defined under the old regime (reference period) could be considered anything above 3 sigma, occuring very rarely (<1% of the time).
Now that bell curve is moving up, with what used to be a rare heat wave becoming much, much more frequent, and heat extremes unheard of under the old regime (5 sigma) becoming about as frequent as the old "extreme heat" (which is now a regular occurence).
As water vapor content of the atmosphere rises with temperature, precipitation is expected to follow a similar pattern.

Think of it as "once every century" events becoming "one every decade" events. And that's for now, things will get progressively nastier with average temperatures rising further.

Of course that's a bit simplified, but for more details one would need to really get into the primary literature.

Well, yeah, you'll see more periods with greater heat if the Earth is warming, which it is. But that's completely not what I meant, nor what the OP stated. He specifically mentioned typhoons, draughts and floods, and that's BS.

Actually power plants are threatened by shutdowns due to low and warm river water in the summer.

Very few of them I suppose. I see no reason otherwise.

If you look at where most of the population of the "Industrialized World" is located, you will find that it is in the southern part of the northern temperate zone, and the adjacent subtropic regions, i.e. increased AC requirements will dominate.

I don't doubt that, but since we currently also spend a whole lot of energy on heating (not just electricity but also from direct sources such as burning wood), the net effect won't be as great as some may assume.

Not forever, but assuming business as usual, and ChIndia catching up to OECD greenhouse gas emission levels per capita would mean temperatures rising for a century or two, with at least 0.2°C per decade, and very likely faster.
For our lifetimes, this equals "permanently".

Why centuries? By some measures China is already quite advanced in its industrialization process. Once you add up China, Japan, Europe and North America you have a very sizeable part of the whole world already on the "flat stage". Considering how the industrialization process of newly industrialized countries tend to be faster than the old ones (and less carbon intensive), I think we're talking of a few decades, not centuries, before "peak carbon".

 

[luiz]

It won't balance out, because that's not how physics works. A warmer world means more energy in the atmosphere, which means more violent and unpredictable weather. It doesn't just balance out evenly such that daily highs and lows increase by X degrees.

In all modesty I know my physics (it's not only climatologists that know physics, or know it the most...)

But what we're talking about is not really about simple physics (it is about physics but in a very complex way that we don't understand very well). It's not at all about "extra energy" in the atmospheric system. The hypothesis is that more heat will lead to more evaporation which will lead to drier land but heavier rains once they fall. But that's a very fragile hypothesis given the pattern (or rather multitude of patterns) we already see in areas which are warm today (and warm weather isn't correlated with unpredictable weather at all). This is something admitted by the IPCC, who limits themselves to stating that global warming may lead to this and that. But what really matters is how the phenomena will interfere with local currents and patterns, and nobody has a clue. It will certainly vary a lot from place to place. To just state "it will lead to more floods and draughts" is as unscientific as it gets.

See Tokala's chart. You absolutely can link them. It's not even very difficult.

Of course a heating world will have more "abnormally hot" years once we define the old average as normal. But that's not what I was talking about.

Oh, I'm well aware that the melting of the Arctic ice caps won't actually raise sea levels. I think it actually slightly lowers them, since the floating ice winds up displacing more water that it does melted.

But the fact that that statement has been oversimplified doesn't change the fact that he's right. Melting ice caps means lower albedo, more dark oceans, more ocean warming, and corresponding thermal expansion. The melting ice is also symptomatic of the larger problem; even if the melting ice didn't alter the planetary albedo, the thermal expansion of the oceans would still raise sea levels.

It was a perfect example of an alarmist article drawing attention to an effect that won't result from the topic of the article.

That is a perfectly true statement.

If they are mysterious we can't know they will be big.

Nobody is being hysterical about anything.

Good one.

You're just harping on the same bloody strawman. We need to make drastic emissions cuts. We also need to address those other problems at the same time; and I would also object to calling them greater, but since I don't know what you're specifically talking about, I won't.

I think any problem that is claiming lives and making people miserable right now is greater than Global Warming.

As for the alternate course you've presenting in the last few words there, that is an option. But all of the estimates we've done suggest that it's cheaper to make cuts now than it is to keep on trucking, and then cope with a warmer world.

We won't make cuts in the timeframe demanded. That's a rock-solid fact.

Another one is we still don't the know the costs associated with GW.

 

[TheLastOne36]

The melting Arctic has outpaced the predictions of almost everyone &#8211; everyone except the few who were called alarmists.

From the Scientific American blogpost. Maybe we should not be so fast to discredit alarmists? mmkay?

 

[Bootstoots]

I for one can barely believe the rate at which climate change appears to be progressing. The dramatic reduction in the Arctic ice sheet's minimum extent over the past six years has exceeded the predictions of all but the most extreme scenarios from a decade ago. There are even signs that we're beginning to see the release of Arctic methane deposits, which nobody really expected to see so quickly. It's not yet enough to measurably affect the climate, but we have no idea how much that trend will accelerate as time goes on. There was a four-day event this summer where ice melted across 97% of the surface of the Greenlandic ice cap. The number of record highs recorded in the past decade has exceeded the number of record lows by a vast margin. The list just goes on and on...

Climate change is a complex enough issue that it leaves a lot of room for obfuscation. You could point out, for instance, that the melting of the Arctic ice cap will not, by itself, raise sea level. This is true in a narrow sense, but it causes a dramatic reduction in the albedo of the sea surface, further accelerating warming in the region that has already seen the strongest effects. It also appears to have significant effects on the weather patterns of the Northern Hemisphere, in particular slowing down the jet stream, making weather systems more persistent.

You could also point out that Al Gore is a filthy hypocrite who has multiple lavish mansions and flies around on a private jet. This is correct, and I for one think that Al Gore did more harm than good to the case for taking action on climate change. Using a polarizing politician as a spokesperson for an issue like this wasn't a wise move in the best of times, and it doesn't help that he has a carbon footprint that is likely in the top .001% of the planet.

You could also point out that a few alarmists think that the planet will turn into Venus or that a 6 C temperature increase would extinguish the human species. These people are simply wrong and don't deserve much discussion. The point remains that nearly all scientists in this field believe that a serious problem is unfolding and that it will have effects that are, on average, highly negative for humans who have adapted to the present climate regime.

I'm still not optimistic that we will manage to drastically reduce carbon emissions without significant economic pain, and I do not think we will be able to power our huge energy demands on renewables alone without accepting intermittency, significant storage problems, multi-trillion dollar infrastructure improvements, and the like. There is some encouraging progress being made, but it appears unlikely that we can mitigate enough of our carbon emissions to hold climate change in check while also using anything like the amount of energy we use today and retaining the ability to obtain it on demand at any hour of the day or night.

We're in for a world with a significantly different climate, and even if this were unimportant, our hydrocarbon reserves will become more limited as the century progresses. This might eventually limit the amount of CO2 we can produce, but not until we have run into serious economic barriers that will cause their own misery. This isn't an apocalypse, and we will still make progress on many fronts, but we may fall well short of our own expectations for this century. I think it's time for us to come to terms with this.

 

[utgotye]

If humans are indeed causing damage to the planet, then there really is only one course of action if the goal is to prevent (or even reverse) further damage: we must eliminate the human race. Just give me a heads up like a week beforehand so I can tie up some loose ends. I know everyone will be gone but I really hate leaving things undone.

 

[tokala]

Why centuries? By some measures China is already quite advanced in its industrialization process. Once you add up China, Japan, Europe and North America you have a very sizeable part of the whole world already on the "flat stage". Considering how the industrialization process of newly industrialized countries tend to be faster than the old ones (and less carbon intensive), I think we're talking of a few decades, not centuries, before "peak carbon".

Sorry, but you don't appear to have thought enough about the mechanisms I am basing my arguments on. Nor to have looked up the actual numbers.

You correctly observed that the "developed world" has an almost flat level of greenhouse gas emissions.
Taking the OECD countries as a convenient metric for the "developed world", the historic and likely future numbers are like that:

OECD has less than 20% of the world population, and that number is shrinking.
Non-OECD per capita emissions are about 1/4 of the OECD value:

Catching up to the lifestyle of the rich world, at present population levels would accordingly roughly triple global greenhouse gas emissions compared to the currents levels.
But population is not static, see the fist graph for reference. Now let's be optimistic and assume that carbon intensity will be indeed be lower for those newly industrializing countries, enough to cancel out the population growth effect.

Than we are still stuck with greenhouse gas emissions three times as high as the present.
Let''s further assume that it will take only 50 years to lift the rest of the world to the western standard of living, and emissions will slowly decline afterwards.

The next step would be to look at how atmospheric CO2 levels would react to such an emission scenario. Problem is, the natural mechanisms that scrub CO2 out of the atmosphere have timescales ranging from decades to millenia:

(full paper: http://mojojojo.uchicago.edu/Projects/archer.2009.ann_rev_tail.pdf) meaning that CO2 concentration will continue to rise fast, even for constant or slowly declining emission levels, for centuries to come. It would probably take emission reductions in the ballpark of 10% per decade to stabilize CO2 concentration on a less-than-century timescale.

But we are not done yet.
Earth's climate system has an enormous inertia when reacting to an external forcing, mainly due to the heat capacity of the oceans, again operating on timescales of decades to millenia.

So even after CO2 concentrations have stabilized, surface temperatures will rise for decades to come, seelevels for millenia.

If you add this all up, my "one or two centuries" of permanent climate change would appear to be on the wildly optimistic side for a business as usual scenario, i.e. your "lets deal with more pressing problems first".

Problem is, the longer business as usual is continued, the higher the likelihood that those "more pressing problems" will be exacerbated by climate change faster than business as usual can solve them.

 

[Borachio]

Things don't look good. I'm not optimistic that people and governments are actually going to do anything significant, and it looks like it will be too little too late anyway. And yet, there's nothing like a common enemy for uniting people.

 

[Aroddo]

Unless you find a way to put science in the bible, all attempts to convince conservatives (who strangely don't give a damn about conserving the environment) are doomed.