7 ms·

What happened last time it was as warm as it’s going to get later this century?

80 points by xoa 8y ago

jseliger 8y ago
I read an excellent book, The Ends of the World, on just this subject: https://jakeseliger.com/2017/09/18/the-ends-of-the-world-peter-brannen https://jakeseliger.com/2017/09/18/the-ends-of-the-world-pet.... But the book gets there through looking at the last five mass extinction events. It turns out that either every one of them, or every one except one, hinged on changes in atmospheric carbon levels, which we didn't realize until relatively recently.
adrianN 8y ago
Obligatory xkcd: https://xkcd.com/1732/ https://xkcd.com/1732/
xoa 8y ago
Does anyone know if there is any party or even organization anywhere right now pushing proper utilization of the free market to at least internalize the current cost of CO2 emissions (though that by itself could not solve the historical lack). It seems like this would actually be one of the few places where a free market should work extremely well: simply set the price of emitting a ton of CO2 at the ratcheted price (defined by bid) of industrial removal (time period of a day or less) a ton plus some assured margin (7%? exact number could be figured out by experts). The government would serve as the pivot, emitters would pay in units at the existing price, so a pool of credits per ton would collect. Anyone who could meet a minimum volume level (the whole point is massive industrial scale removal) would be able to bid for those in whatever amounts they could handle per day/week/month. If they figured out a new scalable way to remove a ton more cheaply, they'd be able to underbid anyone on a more expensive method and collect the much wider margin until they used up the pool at that price, while meanwhile the price for emitters would automatically be adjusted down to the new cost plus minimum margin. The government might have to get the ball rolling by funding an initial plant, but after that it should be self sustaining, and would it make energy prices directly embody the emission cost in a very clean way that would allow the rest of the economy to locally optimize as necessary. Obviously there would be many low level implementation details to work through, but this seems obvious enough that I assume it's been proposed many times. However I haven't been able to figure out the right search terms to find any papers developing it further. I've seen plenty of carbon pricing schemes proposed but all of them seem to use pretty arbitrary rates rather then simply directly internalizing the goal of zero net emissions and letting a market on each side sort out how best the meet that goal in any given place. I'd love it if anyone knows where I could better search, after some recent work I do have access to college resources again so academic journals would be fine too. There are also of course plenty of awful schemes by various political parties pushing various subsidies or "efficiency improvements" or whatever in a command-control fashion, but that's not great either. Any HNers who have ideas/sources would be awesome.
- collyw 8y ago
  So far the free market has failed spectacularly at addressing global warming.
  - organsnyder 8y ago
    We need to price in the externality. A carbon tax is one way to do that. Instead, we have various direct approaches—fuel efficiency standards, subsidies...—that work with varying degrees of success.
  - ChristianBundy 8y ago
    > So far the free market has failed spectacularly. FTFY
    - pitaj 8y ago
      1. We haven't had anything close to a free market for many years. 2. The market pulling billions of people out of poverty is probably the opposite of failure.
  - xoa 8y ago
    The free market has never been used to address global warming (it's badly used in general in fact, possibly in part because few people seem to actually understand what it is or even internalize that it's a tool at all, not an end, and like any tool there are applications it is a poor fit for). Amongst the foundational requirements for a free market to work at all is that the price should embody all costs. There are some problems of course where this simply isn't very practical, particularly ones that are heavily non-linear/non-reversible. But that's not the case for carbon emissions, in fact it's a pretty good fit. The problem is "release of fossil/long term stored carbon into the atmosphere", it's easy to measure at various points at the fuel level, and since it's a gas that will evenly diffuse worldwide and is uniform removal from the atmosphere can take place anywhere in the world by anyone using any method. That makes it well suited to abstraction, with a market system on each side of the equation and government acting as a pivot. Wouldn't even require global buy-in to make a difference given that the energy market is primarily globalized anyway, if a few major polities decided to require it and also made access to their own markets take it into account it'd have a major effect no matter what anyone else wanted.
macinjosh 8y ago
Global warming is real and humans contribute to it. Just stating that so I am not called a 'denier' as I have been before. That being said, the computer models predicting what the consequences of global warming will be, have greatly over estimated (at least the timeline of) real world impacts. Since I was a kid I've heard in the news that in the next 5 years or 10 years there will be all these catastrophes linked to global warming and I have yet to see them come true. I remember the BBC reporting years ago that the children of today would only know snow from what they've seen in snow globes, things like that. I think part of the reason for inaction is due to the news media over simplifying the problem and reporting (perhaps even exaggerating) the worst long term predictions.
- wilsonnb2 8y ago
  Yeah the media's bias for sensationalism has really bitten us on the ass on this one. Of course they're going to heavily report anything that can be interpreted as "the world is ending", and now there is a boy who cried wolf effect whenever they report anything on global warming. The media should be more responsible about this kind of thing.
- seanalltogether 8y ago
  With regards to England, it is slowly going that direction. https://www.telegraph.co.uk/news/2017/01/12/often-does-snow-fall-uk-getting-rarer/ https://www.telegraph.co.uk/news/2017/01/12/often-does-snow-...
- Jill_the_Pill 8y ago
  The numerous one-in-a-thousand-year floods don't get you? The super-typhoons and unprecedented hurricanes? Drought and the human migration motivated by drought and flood? Species extinction? Wildfires? Loss of islands? I think it was the photos of disinterred coffins floating through the flooded streets of New Orleans that first really hit me: it's here.
  - danielmg 8y ago
    I don't think you read all of his comment. Picking a single event like New Orleans isn't great evidence. I lived through a once in 300 years hurricane in southern England in '87 - that tells us nothing. But the increasing frequency of adverse events and once in a x years events is starting to nod its head in the direction of the impacts of global warming starting to manifest. The point he made is a good one - media sensationalism, supported by people who should know better; it does more harm than good. The future looks bleak as we, in the west, can go 100% nuke, zero carbon etc but it's like a fart in a jacuzzi compared to what China will bring as its economy scales to western per-capita size.
throwaway5752 8y ago
I thought this was going to be about the Paleocene–Eocene Thermal Maximum (https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Thermal_Maximum https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Therm...) or (and?) the clathrate gun hypothesis (https://en.wikipedia.org/wiki/Clathrate_gun_hypothesis https://en.wikipedia.org/wiki/Clathrate_gun_hypothesis). Sobering stuff, particularly heartbreaking for parents of young children. edit: this is getting downvoted, so perhaps it's a miscommunication. I am most worried about heat waves and disrupted weather patterns causing more common crop failures and the geopolitical stress/conflict that will lead to. You can see the beginnings of this in Syria, Yemen, and various N. African countries where climate change induced drought was the underlying cause for the civic unrest. Look at the migrant populations fleeing these areas. I don't mean anything melodramatic, just that this will be a period of hardship and suffering greater than what we've become accustomed to in recent history.
antognini 8y ago
This article is about the Mid-Miocene Climate Optimum, which was a period of 5 degrees C of warming about 15 million years ago. Another similar event is the Paleocene-Eocene Thermal Maximum, which was a period of warming (6 degrees C in 20,000 years) about 55 million years ago. The PETM was in response to a massive increase in atmospheric CO2 (several times more than humans have added), though what caused the injection of CO2 is currently unknown. Interestingly, although during the PETM the Earth had no polar ice caps to begin with there was still a rise in sea levels simply due to the thermal expansion of the ocean. There was a great deep dive into the event on the podcast In Our Time by three climatologists: https://www.bbc.co.uk/programmes/b08hpmmf https://www.bbc.co.uk/programmes/b08hpmmf
- throwaway5752 8y ago
  You should note that the PETM CO2 increase was over multiple orders of magnitude (appr. 20,000 year vs 100) and theoretical rate of emission was 1-2 orders of magnitude less than the current rate.
  - antognini 8y ago
    While that's probably true, it's not known for certain what the rate of emission was. 20,000 years is only an upper bound. It's possible that the process that led to the CO2 emissions happened over very short timescales (e.g., a comet impact or volcanic activity). Until we know the process, we can't constrain the rate.
    - throwaway5752 8y ago
      I upvoted you, thank you for replying, but please give me a bit of charity and understand I was replying with the standard geological uncertainties assumed. But my understanding is the best fit is volcanic activity by peat or coal beds over a much longer relative timeframe than current emissions.
mkempe 8y ago
A better and much more recent proxy observation for the effect of a warming climate is the Eemian [1] aka the last interglacial. Peak temperature 125k years ago was at least 2 C higher than today, and global sea-level was 8-9 m higher (of which less than 0.5 m is attributable to thermal expansion of ocean water). Scandinavia was an island. [1] https://en.wikipedia.org/wiki/Eemian https://en.wikipedia.org/wiki/Eemian
FreeFull 8y ago
The one big problem I don't see talked about as much for some reason is ocean acidification. Given more of the surface of the planet is covered in ocean than in land, and the influence the oceans have on everything, it's pretty hard not to get worried about it. One consequence that is already happening (partly due to ocean acidification, and partly due to water getting warmer) is coral reef die-offs/bleaching.

80 points by xoa 8y ago

I read an excellent book, The Ends of the World, on just this subject: https://jakeseliger.com/2017/09/18/the-ends-of-the-world-peter-brannen https://jakeseliger.com/2017/09/18/the-ends-of-the-world-pet.... But the book gets there through looking at the last five mass extinction events. It turns out that either every one of them, or every one except one, hinged on changes in atmospheric carbon levels, which we didn't realize until relatively recently.

adrianN 8y ago

Obligatory xkcd: https://xkcd.com/1732/ https://xkcd.com/1732/

xoa 8y ago

Does anyone know if there is any party or even organization anywhere right now pushing proper utilization of the free market to at least internalize the current cost of CO2 emissions (though that by itself could not solve the historical lack). It seems like this would actually be one of the few places where a free market should work extremely well: simply set the price of emitting a ton of CO2 at the ratcheted price (defined by bid) of industrial removal (time period of a day or less) a ton plus some assured margin (7%? exact number could be figured out by experts). The government would serve as the pivot, emitters would pay in units at the existing price, so a pool of credits per ton would collect. Anyone who could meet a minimum volume level (the whole point is massive industrial scale removal) would be able to bid for those in whatever amounts they could handle per day/week/month. If they figured out a new scalable way to remove a ton more cheaply, they'd be able to underbid anyone on a more expensive method and collect the much wider margin until they used up the pool at that price, while meanwhile the price for emitters would automatically be adjusted down to the new cost plus minimum margin. The government might have to get the ball rolling by funding an initial plant, but after that it should be self sustaining, and would it make energy prices directly embody the emission cost in a very clean way that would allow the rest of the economy to locally optimize as necessary. Obviously there would be many low level implementation details to work through, but this seems obvious enough that I assume it's been proposed many times. However I haven't been able to figure out the right search terms to find any papers developing it further. I've seen plenty of carbon pricing schemes proposed but all of them seem to use pretty arbitrary rates rather then simply directly internalizing the goal of zero net emissions and letting a market on each side sort out how best the meet that goal in any given place. I'd love it if anyone knows where I could better search, after some recent work I do have access to college resources again so academic journals would be fine too. There are also of course plenty of awful schemes by various political parties pushing various subsidies or "efficiency improvements" or whatever in a command-control fashion, but that's not great either. Any HNers who have ideas/sources would be awesome.

collyw 8y ago
So far the free market has failed spectacularly at addressing global warming.
- organsnyder 8y ago
  We need to price in the externality. A carbon tax is one way to do that. Instead, we have various direct approaches—fuel efficiency standards, subsidies...—that work with varying degrees of success.
- ChristianBundy 8y ago
  > So far the free market has failed spectacularly. FTFY
  - pitaj 8y ago
    1. We haven't had anything close to a free market for many years. 2. The market pulling billions of people out of poverty is probably the opposite of failure.
- xoa 8y ago
  The free market has never been used to address global warming (it's badly used in general in fact, possibly in part because few people seem to actually understand what it is or even internalize that it's a tool at all, not an end, and like any tool there are applications it is a poor fit for). Amongst the foundational requirements for a free market to work at all is that the price should embody all costs. There are some problems of course where this simply isn't very practical, particularly ones that are heavily non-linear/non-reversible. But that's not the case for carbon emissions, in fact it's a pretty good fit. The problem is "release of fossil/long term stored carbon into the atmosphere", it's easy to measure at various points at the fuel level, and since it's a gas that will evenly diffuse worldwide and is uniform removal from the atmosphere can take place anywhere in the world by anyone using any method. That makes it well suited to abstraction, with a market system on each side of the equation and government acting as a pivot. Wouldn't even require global buy-in to make a difference given that the energy market is primarily globalized anyway, if a few major polities decided to require it and also made access to their own markets take it into account it'd have a major effect no matter what anyone else wanted.

macinjosh 8y ago

Global warming is real and humans contribute to it. Just stating that so I am not called a 'denier' as I have been before. That being said, the computer models predicting what the consequences of global warming will be, have greatly over estimated (at least the timeline of) real world impacts. Since I was a kid I've heard in the news that in the next 5 years or 10 years there will be all these catastrophes linked to global warming and I have yet to see them come true. I remember the BBC reporting years ago that the children of today would only know snow from what they've seen in snow globes, things like that. I think part of the reason for inaction is due to the news media over simplifying the problem and reporting (perhaps even exaggerating) the worst long term predictions.

wilsonnb2 8y ago
Yeah the media's bias for sensationalism has really bitten us on the ass on this one. Of course they're going to heavily report anything that can be interpreted as "the world is ending", and now there is a boy who cried wolf effect whenever they report anything on global warming. The media should be more responsible about this kind of thing.
seanalltogether 8y ago
With regards to England, it is slowly going that direction. https://www.telegraph.co.uk/news/2017/01/12/often-does-snow-fall-uk-getting-rarer/ https://www.telegraph.co.uk/news/2017/01/12/often-does-snow-...
Jill_the_Pill 8y ago
The numerous one-in-a-thousand-year floods don't get you? The super-typhoons and unprecedented hurricanes? Drought and the human migration motivated by drought and flood? Species extinction? Wildfires? Loss of islands? I think it was the photos of disinterred coffins floating through the flooded streets of New Orleans that first really hit me: it's here.
- danielmg 8y ago
  I don't think you read all of his comment. Picking a single event like New Orleans isn't great evidence. I lived through a once in 300 years hurricane in southern England in '87 - that tells us nothing. But the increasing frequency of adverse events and once in a x years events is starting to nod its head in the direction of the impacts of global warming starting to manifest. The point he made is a good one - media sensationalism, supported by people who should know better; it does more harm than good. The future looks bleak as we, in the west, can go 100% nuke, zero carbon etc but it's like a fart in a jacuzzi compared to what China will bring as its economy scales to western per-capita size.

throwaway5752 8y ago

I thought this was going to be about the Paleocene–Eocene Thermal Maximum (https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Thermal_Maximum https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Therm...) or (and?) the clathrate gun hypothesis (https://en.wikipedia.org/wiki/Clathrate_gun_hypothesis https://en.wikipedia.org/wiki/Clathrate_gun_hypothesis). Sobering stuff, particularly heartbreaking for parents of young children. edit: this is getting downvoted, so perhaps it's a miscommunication. I am most worried about heat waves and disrupted weather patterns causing more common crop failures and the geopolitical stress/conflict that will lead to. You can see the beginnings of this in Syria, Yemen, and various N. African countries where climate change induced drought was the underlying cause for the civic unrest. Look at the migrant populations fleeing these areas. I don't mean anything melodramatic, just that this will be a period of hardship and suffering greater than what we've become accustomed to in recent history.

antognini 8y ago

This article is about the Mid-Miocene Climate Optimum, which was a period of 5 degrees C of warming about 15 million years ago. Another similar event is the Paleocene-Eocene Thermal Maximum, which was a period of warming (6 degrees C in 20,000 years) about 55 million years ago. The PETM was in response to a massive increase in atmospheric CO2 (several times more than humans have added), though what caused the injection of CO2 is currently unknown. Interestingly, although during the PETM the Earth had no polar ice caps to begin with there was still a rise in sea levels simply due to the thermal expansion of the ocean. There was a great deep dive into the event on the podcast In Our Time by three climatologists: https://www.bbc.co.uk/programmes/b08hpmmf https://www.bbc.co.uk/programmes/b08hpmmf

throwaway5752 8y ago
You should note that the PETM CO2 increase was over multiple orders of magnitude (appr. 20,000 year vs 100) and theoretical rate of emission was 1-2 orders of magnitude less than the current rate.
- antognini 8y ago
  While that's probably true, it's not known for certain what the rate of emission was. 20,000 years is only an upper bound. It's possible that the process that led to the CO2 emissions happened over very short timescales (e.g., a comet impact or volcanic activity). Until we know the process, we can't constrain the rate.
  - throwaway5752 8y ago
    I upvoted you, thank you for replying, but please give me a bit of charity and understand I was replying with the standard geological uncertainties assumed. But my understanding is the best fit is volcanic activity by peat or coal beds over a much longer relative timeframe than current emissions.

mkempe 8y ago

A better and much more recent proxy observation for the effect of a warming climate is the Eemian [1] aka the last interglacial. Peak temperature 125k years ago was at least 2 C higher than today, and global sea-level was 8-9 m higher (of which less than 0.5 m is attributable to thermal expansion of ocean water). Scandinavia was an island. [1] https://en.wikipedia.org/wiki/Eemian https://en.wikipedia.org/wiki/Eemian

FreeFull 8y ago

The one big problem I don't see talked about as much for some reason is ocean acidification. Given more of the surface of the planet is covered in ocean than in land, and the influence the oceans have on everything, it's pretty hard not to get worried about it. One consequence that is already happening (partly due to ocean acidification, and partly due to water getting warmer) is coral reef die-offs/bleaching.