5 ms·

It's not the absolute temperature that is alarming. It is the change in temperature. Previous changes have been over millennia. These changes have been over 100

by daveguy 10y ago

It's not the absolute temperature that is alarming. It is the change in temperature. Previous changes have been over millennia. These changes have been over 100 years. The graphic that puts it in the best perspective I have seen is an xkcd cartoon (be sure to scroll all the way to the end): https://xkcd.com/1732/ https://xkcd.com/1732/

bolololo 10y ago
How do we know what was the temperature 1000 or 3000 years ago?
zeveb 10y ago
You know, my takeaway from that graphic is that higher temperatures appear to be pretty well-correlated with improved human quality of life. And of course the graphic doesn't show a cost-benefit analysis for any of its three future scenarios. Would it be worth a nickel to preserve the current environment exactly as it is? Maybe (although maybe some change would be good; I don't know). Would it be worth $1 quadrillion a day to prevent a single town of 1,000 people from being submerged by rising oceans? Almost certainly not. What are the costs of each scenario, and what are the benefits? Is it worth losing a few houses in Miami if it means that Oslo produces more food? That the world has always been changing has always been true, whether respecting climate or any number of other factors. That we're affected by change has also always been true. That we can have an effect on it is relatively new, and that we ought to is unproven. Frankly, the 20th century makes me very suspicious of any technocratic solution which claims to be able to predict every possibility and make the best choice (remember the Aswan Dam!). That doesn't mean we should do nothing, either (doing nothing is itself a choice which needs to be justified too!), but it means we should be very suspicious of easy answers which claim to be all benefit and no cost.
- codecamper 10y ago
  how's that for mixing correlation & causation. Sorta like, I've noticed that I have a good time when my bank account is low. Low bank accounts must mean good life havin'!
  - zeveb 10y ago
    > how's that for mixing correlation & causation. I'm just noting the correlation. In some cases it's likely that causation goes one way (e.g. post-industrial changes), but in other cases it's not (e.g. well before there were enough men to make a mark on the Earth). Of course, even back then there's still a post hoc, propter hoc fallacy to watch out for: the mere fact that civilisation has done better as the world has warmed — if it is even a fact — doesn't mean that warming is the cause. It could be as simple as increased sunlight leading to both more plant growth and more heat, and more plant growth leading to more food & other resources for man's use. Which — if the case — would raise the question of how much is too much: a greenhouse in winter can be great, but an unvented greenhouse in summer can be unlivable for plants or anything else.
- sharemywin 10y ago
  Why not ask a bean counter? http://evanmills.lbl.gov/pubs/pdf/climate-action-insurance.pdf http://evanmills.lbl.gov/pubs/pdf/climate-action-insurance.p... Also, look up US drought and climate refugees if you want to see where the real problems are going to come from. Turning huge swathes of the equator uninhabitable just seems like a bad idea to me.
- jamesblonde 10y ago
  You really don't understand anything about dynamical systems do you? It's incredibly naive to assume we will land in some nice stable equilibrium where it's a couple of degrees warmer globally. The truth is we don't know where the climate will end up, but we know that we are in the process of exiting our current 'stable equilibrium'. The worst case scenario (and that is the only one we should be concerned with!) is a global mass extinction event. We've already had 5 of them - one of which was due to runaway greenhouse warming - https://cosmosmagazine.com/palaeontology/big-five-extinctions https://cosmosmagazine.com/palaeontology/big-five-extinction...
  - randomgyatwork 10y ago
    If 5 global mass extinction events have already happened without any human intervention (positive or negative), why do we think we can stop the 6? I'd assume from that data, that its going to happen regardless of what we do.
    - kbart 10y ago
      "why do we think we can stop the 6?" We don't know, but it doesn't mean we should be actively trying to make it happen sooner. Heck, there's a pretty big difference if next mass extinction happens few years/decades from now or few thousand years in a future, when we might be better prepared for it. We all gonna die one day, that doesn't mean we shouldn't try to improve our lives now or make it better for our children.
      - randomgyatwork 10y ago
        Haven't we been trying to improve our lives and the lives of our children for 30,000 odd years... Take a look at the situation we created, this world is the direct result of our desire to make things better... We've literally destroyed the earth.
        huherto 10y ago
        We are not destroying the earth. The earth will go on with or without us. We are destroying the future of millions of humans. It will cause a great deal of pain and suffering. It may even cause the extension of our civilization or even our species.
- emodendroket 10y ago
  A huge number of the world's greatest cities are on the coast since cities have a tendency to develop around ports.
  - zeveb 10y ago
    > A huge number of the world's greatest cities are on the coast since cities have a tendency to develop around ports. Sure. That effects the cost of rising sea levels and the benefit of lowered sea levels. I'm not saying, 'let's do nothing!': I'm saying, 'let's perform a cost-benefit analysis' and 'I'm suspicious of anyone who has high confidence in his cost-benefit analysis'[1]. It's remarkable that so many folks find those to be distressing views. [1] Particularly if his analysis supports giving him and people like him the sort of social power that great apes tend to crave like a drug. The Aztec priests had every incentive to believe that the human sacrifices they performed kept the Sun in his track — I won't say that the acted in bad faith (although their actual faith was appallingly bad: if one's religion requires ripping the hearts out of people and then engaging in cannibalism, maybe one should re-evaluate one's religious options), but they were still factually wrong.
    - emodendroket 10y ago
      I mean, how much do you figure flooding New York permanently would cost? Hurricane Sandy cost billions of dollars.
      - zeveb 10y ago
        > I mean, how much do you figure flooding New York permanently would cost? I honestly don't know the answer; I never said or implied that I did: I just noted the questions we have to answer to make a rational — rather than an emotional — decision. > Hurricane Sandy cost billions of dollars. True, but an awful lot of that was repair, wasn't it? If you abandon something, you don't need to spend money fixing it first. There would certainly be huge costs in losing New York City, but there would be some benefits too. And, again, taking the measures needed to not-lose-New-York isn't free: there are costs associated with that course of action. It truly boggles my mind that so many folks here think that, 'something must be done; this is something; this must be done!' is valid when applied to climate change, when we would all recognise it as invalid in a software-development context.
- lobster_johnson 10y ago
  Global warming doesn't mean "it'll get a few degrees warmer and sea levels will rise a bit and things will settle into a new normal and we'll all have to cope by just moving inland a bit and no longer having to shovel snow in the winter". The ecosystem is a huge, dynamic, non-linear system. A key characteristic of a non-linear system is that relatively small changes can have huge cascading effects. When you disrupt the system by introducing an imbalance — by pumping out CO2 — the result is usually a period of chaos until the system settles on a new equilibrium. We don't know what equilibrium is exactly, because we don't know what the first step is — there'll be a cascade of effects. For example, we know that melting ice will decrease ocean salinity, and we know that the balance of salinity is crucial in driving the global ocean conveyor belt, which in turn has an impact on local climates, storms, wind patterns, rainfall. That's ignoring the cascading effects of melting tundras unlocking enormous methane deposits that could turn Earth into another Venus. In the short term, the effect on agriculture is probably the scariest problem, even scarier than rising sealevels forcing coastal settlements inland (mass displacement has never been a happy occurrence for the people being displaced or those who have to receive them). Society is completely dependent on food production to stay civilized. If crops fail, livestock die, too, and eventually people.

by daveguy 10y ago

bolololo 10y ago

How do we know what was the temperature 1000 or 3000 years ago?

zeveb 10y ago

You know, my takeaway from that graphic is that higher temperatures appear to be pretty well-correlated with improved human quality of life. And of course the graphic doesn't show a cost-benefit analysis for any of its three future scenarios. Would it be worth a nickel to preserve the current environment exactly as it is? Maybe (although maybe some change would be good; I don't know). Would it be worth $1 quadrillion a day to prevent a single town of 1,000 people from being submerged by rising oceans? Almost certainly not. What are the costs of each scenario, and what are the benefits? Is it worth losing a few houses in Miami if it means that Oslo produces more food? That the world has always been changing has always been true, whether respecting climate or any number of other factors. That we're affected by change has also always been true. That we can have an effect on it is relatively new, and that we ought to is unproven. Frankly, the 20th century makes me very suspicious of any technocratic solution which claims to be able to predict every possibility and make the best choice (remember the Aswan Dam!). That doesn't mean we should do nothing, either (doing nothing is itself a choice which needs to be justified too!), but it means we should be very suspicious of easy answers which claim to be all benefit and no cost.

codecamper 10y ago
how's that for mixing correlation & causation. Sorta like, I've noticed that I have a good time when my bank account is low. Low bank accounts must mean good life havin'!
- zeveb 10y ago
  > how's that for mixing correlation & causation. I'm just noting the correlation. In some cases it's likely that causation goes one way (e.g. post-industrial changes), but in other cases it's not (e.g. well before there were enough men to make a mark on the Earth). Of course, even back then there's still a post hoc, propter hoc fallacy to watch out for: the mere fact that civilisation has done better as the world has warmed — if it is even a fact — doesn't mean that warming is the cause. It could be as simple as increased sunlight leading to both more plant growth and more heat, and more plant growth leading to more food & other resources for man's use. Which — if the case — would raise the question of how much is too much: a greenhouse in winter can be great, but an unvented greenhouse in summer can be unlivable for plants or anything else.
sharemywin 10y ago
Why not ask a bean counter? http://evanmills.lbl.gov/pubs/pdf/climate-action-insurance.pdf http://evanmills.lbl.gov/pubs/pdf/climate-action-insurance.p... Also, look up US drought and climate refugees if you want to see where the real problems are going to come from. Turning huge swathes of the equator uninhabitable just seems like a bad idea to me.
jamesblonde 10y ago
You really don't understand anything about dynamical systems do you? It's incredibly naive to assume we will land in some nice stable equilibrium where it's a couple of degrees warmer globally. The truth is we don't know where the climate will end up, but we know that we are in the process of exiting our current 'stable equilibrium'. The worst case scenario (and that is the only one we should be concerned with!) is a global mass extinction event. We've already had 5 of them - one of which was due to runaway greenhouse warming - https://cosmosmagazine.com/palaeontology/big-five-extinctions https://cosmosmagazine.com/palaeontology/big-five-extinction...
- randomgyatwork 10y ago
  If 5 global mass extinction events have already happened without any human intervention (positive or negative), why do we think we can stop the 6? I'd assume from that data, that its going to happen regardless of what we do.
  - kbart 10y ago
    "why do we think we can stop the 6?" We don't know, but it doesn't mean we should be actively trying to make it happen sooner. Heck, there's a pretty big difference if next mass extinction happens few years/decades from now or few thousand years in a future, when we might be better prepared for it. We all gonna die one day, that doesn't mean we shouldn't try to improve our lives now or make it better for our children.
    - randomgyatwork 10y ago
      Haven't we been trying to improve our lives and the lives of our children for 30,000 odd years... Take a look at the situation we created, this world is the direct result of our desire to make things better... We've literally destroyed the earth.
      - huherto 10y ago
        We are not destroying the earth. The earth will go on with or without us. We are destroying the future of millions of humans. It will cause a great deal of pain and suffering. It may even cause the extension of our civilization or even our species.
emodendroket 10y ago
A huge number of the world's greatest cities are on the coast since cities have a tendency to develop around ports.
- zeveb 10y ago
  > A huge number of the world's greatest cities are on the coast since cities have a tendency to develop around ports. Sure. That effects the cost of rising sea levels and the benefit of lowered sea levels. I'm not saying, 'let's do nothing!': I'm saying, 'let's perform a cost-benefit analysis' and 'I'm suspicious of anyone who has high confidence in his cost-benefit analysis'[1]. It's remarkable that so many folks find those to be distressing views. [1] Particularly if his analysis supports giving him and people like him the sort of social power that great apes tend to crave like a drug. The Aztec priests had every incentive to believe that the human sacrifices they performed kept the Sun in his track — I won't say that the acted in bad faith (although their actual faith was appallingly bad: if one's religion requires ripping the hearts out of people and then engaging in cannibalism, maybe one should re-evaluate one's religious options), but they were still factually wrong.
  - emodendroket 10y ago
    I mean, how much do you figure flooding New York permanently would cost? Hurricane Sandy cost billions of dollars.
    - zeveb 10y ago
      > I mean, how much do you figure flooding New York permanently would cost? I honestly don't know the answer; I never said or implied that I did: I just noted the questions we have to answer to make a rational — rather than an emotional — decision. > Hurricane Sandy cost billions of dollars. True, but an awful lot of that was repair, wasn't it? If you abandon something, you don't need to spend money fixing it first. There would certainly be huge costs in losing New York City, but there would be some benefits too. And, again, taking the measures needed to not-lose-New-York isn't free: there are costs associated with that course of action. It truly boggles my mind that so many folks here think that, 'something must be done; this is something; this must be done!' is valid when applied to climate change, when we would all recognise it as invalid in a software-development context.
lobster_johnson 10y ago
Global warming doesn't mean "it'll get a few degrees warmer and sea levels will rise a bit and things will settle into a new normal and we'll all have to cope by just moving inland a bit and no longer having to shovel snow in the winter". The ecosystem is a huge, dynamic, non-linear system. A key characteristic of a non-linear system is that relatively small changes can have huge cascading effects. When you disrupt the system by introducing an imbalance — by pumping out CO2 — the result is usually a period of chaos until the system settles on a new equilibrium. We don't know what equilibrium is exactly, because we don't know what the first step is — there'll be a cascade of effects. For example, we know that melting ice will decrease ocean salinity, and we know that the balance of salinity is crucial in driving the global ocean conveyor belt, which in turn has an impact on local climates, storms, wind patterns, rainfall. That's ignoring the cascading effects of melting tundras unlocking enormous methane deposits that could turn Earth into another Venus. In the short term, the effect on agriculture is probably the scariest problem, even scarier than rising sealevels forcing coastal settlements inland (mass displacement has never been a happy occurrence for the people being displaced or those who have to receive them). Society is completely dependent on food production to stay civilized. If crops fail, livestock die, too, and eventually people.