6 ms·

At 4C of heating, you cannot grow food in any reasonable quantity with any reliability, period. 4C is the collapse of modern civilization at the very least (in

At 4C of heating, you cannot grow food in any reasonable quantity with any reliability, period. 4C is the collapse of modern civilization at the very least (in fact likely earlier due to increased geopolitical instability and tensions due to dwindling resources, combined with the availability of nuclear weapons), with a massive die-off of humans along with it.

trashtester 2y ago
Many places could increase food production to twice what it is today if 5C warmer.
- duozerk 2y ago
  We're at +1.5C, more or less, and growing the usual grapes in France - of all places - is already becoming much harder (they keep dying of frost after waking up due to wild temperature swings). At +5C, there is no growing food in any substantial amount outside of high tech, low yield approaches; approaches that depend on complex planetary supply chains (both for initial deployment and maintenance), which will have disappeared by then.
  - trashtester 2y ago
    > At +5C, there is no growing food in any substantial amount outside of high tech, It seems you have some specific geographic region in mind. Earth has a lot of regions that are more than 5C colder than the most fertile regions. People adapt. People move. Sometimes they fight wars about it. This has happened many times before. We're currently living it the most peaceful, prosperous and safest period that humanity has ever experienced. (Despite what social media is tricking our brains into believing). In the future we will surely live through periods that are closer to the average. But I'm not seeing any extinction-level events due to climate change within the next few hundred years. AGI or nukes, on the other hand, they both DO have the potential to end us as a species.
    - saagarjha 2y ago
      You seem to think that a couple of degrees just applies uniformly across the planet, or to a specific location, transforming somewhere cold into something which is now suddenly hospitable. That isn't how climate change works. It doesn't mean that Canada will suddenly be nice and balmy year-round; it means that the climate will fluctuate more wildly and wreak havoc on our agriculture, as described in the comment above. The temperature change is a global average, and your local experience is going to be a lot worse at the extremes.
      - trashtester 2y ago
        > You seem to think that a couple of degrees just applies uniformly across the planet I don't believe that at all. I even studied the IPCC for how their various scenarios lead to different levels of increased heat in different places. When it comes to fluctuations, there are several types. An obvious one is wind, which will probably become noticeably more chaotic with more energy. Another is temperature. Temperature variations generally depend on humidity and wind. As winds get stronger, that in isolation leads to some increase in temperature variations. For humidity (both at ground level and in the atmosphere), increased humidity leads to lower temperature variations. There are also precipitation. Higher temperatures lead to heavier rain (when it rains), and can increase the likelihood of hailstorms. There are also extreme weather patterns that become more common when it gets colder. While tropical storms and hurricanes increase in frequency in hot weather, more laminar storms ("winter gales") get more common when the weather is colder. I believe this is because the LACK of turbulence/chaos means there are fewer factors that can break up such storms. This last type is common in places like Canada, Scandinavia or Siberia now, and come almost exclusively during winter. Btw, the impact of increased temperature on weather is something that we can already observe on Earth today, simply by travelling between different weather zones. While SOME of the extra energy can affect areas far away from where the heating occurs, a lot of the effects are local or regional. That means that it's likely that Temperate Zone type weather is going to shift a bit to the North, and include a greater proportion of Canada, Scandinavia and Russia. These areas will then get weather more similar to places like the US/German/China today. The southern parts of the temperate zone is likely to see weather patterns that resemble tropical (or desert) weather zones. Much of the US can be more like Mexico, France can be more like Morocco or Greece, Sothern China more like Thailand, and so on. This means that areas that get warmer AND dryer (like Spain, Italy and France, probably) will get some of the variations currently seen in Sahara. But it doesn't mean that the temperature fluctuations get greater everywhere. Some areas become more humid, and that means lower fluctuations. Btw, for humans, dryer weather can be an advantage, since it allows us to dissipate heat much more easily. For farming it's less ideal. Places like Saudi Arabia could go in the opposite direction, with higher humidity and more rain, farming could become easier, but the risk of wet bulbs could also go up. Anyway, while it is true that more energy in the atmosphere ON average increases the frequency of most types of extreme weather, it is not true that it will increase all types of extreme weather everywhere. EDIT: Here's a map: https://archive.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-3-2-3.html https://archive.ipcc.ch/publications_and_data/ar4/wg1/en/ch1...
- mrguyorama 2y ago
  "5C warmer" doesn't mean a uniform increase in temperature of 5 degrees at all times. It means "5 * the thermal mass of the earth's biosphere" worth of extra energy in an extremely chaotic system that is currently in a local stable point, but doesn't have to stay there.
  - trashtester 2y ago
    A 5C warming is indeed likely to make a few areas uninhabitable. I'm not saying climate change is not a problem. I'm just saying it's not an extinction event. But keep in mind that the areas that tend to get the greatest warming tend to be the dry ones. In such places, sweating will still allow human bodies to regulate body heat, if air conditioning breaks down.
    - mrexroad 2y ago
      I think you missed the above comment’s point about risk to stability in a chaotic system…
      - trashtester 2y ago
        That part looked like gibberish.... Maybe rewrite to make it more clear?
        mrexroad 2y ago
        Stability in a chaotic system is precarious. Changes, even if small or seemingly trivial, can cause massive cascading effects from positive/negative feedback loops. Sigh, I don’t mean to sound like a dick, but if that’s gibberish then you might want to strengthen some of the foundational understandings around systems.
        trashtester 2y ago
        I'm familiar with chaos theory, and not rejecting issues related to chaotic systems. But this part doesn't really seem well formed: > It means "5 * the thermal mass of the earth's biosphere" worth of extra energy Here it seems that the units were missing, at best. The extra energy would be "5K * the heat capacity of the biosphere (in J/K)" > in an extremely chaotic system that is currently in a local stable point, but doesn't have to stay there. First of all, I don't think the current state is THAT stable. And when it comes to any disturbance to the stability caused by the extra energy, that's what we have climate scientists for. Specifically, those are the ones that need to assign specific probabilities to the varous scenarios available. For instance, while it is POSSIBLE that a result of the chaotic dynamics of the system would be that the Gulf Stream got reversed, it seems that the curren consensus is that this is highly unlikely. However, there are a lot of other effects that would be highly likely, such as an increased rate of hurricanes for instance. But hurricanes is not a state of the whole system, it's basically just a type of weather that gets more common. So, maybe "gibberish" was not the perfect word to describe it, as I was able to parse it. It's just that it didn't say anything specific. It was more at the level "It's getting chaotic, and chaos is scary", without making any specific predictions or producing references.
goatlover 2y ago
Source for these claims?

trashtester 2y ago

Many places could increase food production to twice what it is today if 5C warmer.

duozerk 2y ago
We're at +1.5C, more or less, and growing the usual grapes in France - of all places - is already becoming much harder (they keep dying of frost after waking up due to wild temperature swings). At +5C, there is no growing food in any substantial amount outside of high tech, low yield approaches; approaches that depend on complex planetary supply chains (both for initial deployment and maintenance), which will have disappeared by then.
- trashtester 2y ago
  > At +5C, there is no growing food in any substantial amount outside of high tech, It seems you have some specific geographic region in mind. Earth has a lot of regions that are more than 5C colder than the most fertile regions. People adapt. People move. Sometimes they fight wars about it. This has happened many times before. We're currently living it the most peaceful, prosperous and safest period that humanity has ever experienced. (Despite what social media is tricking our brains into believing). In the future we will surely live through periods that are closer to the average. But I'm not seeing any extinction-level events due to climate change within the next few hundred years. AGI or nukes, on the other hand, they both DO have the potential to end us as a species.
  - saagarjha 2y ago
    You seem to think that a couple of degrees just applies uniformly across the planet, or to a specific location, transforming somewhere cold into something which is now suddenly hospitable. That isn't how climate change works. It doesn't mean that Canada will suddenly be nice and balmy year-round; it means that the climate will fluctuate more wildly and wreak havoc on our agriculture, as described in the comment above. The temperature change is a global average, and your local experience is going to be a lot worse at the extremes.
    - trashtester 2y ago
      > You seem to think that a couple of degrees just applies uniformly across the planet I don't believe that at all. I even studied the IPCC for how their various scenarios lead to different levels of increased heat in different places. When it comes to fluctuations, there are several types. An obvious one is wind, which will probably become noticeably more chaotic with more energy. Another is temperature. Temperature variations generally depend on humidity and wind. As winds get stronger, that in isolation leads to some increase in temperature variations. For humidity (both at ground level and in the atmosphere), increased humidity leads to lower temperature variations. There are also precipitation. Higher temperatures lead to heavier rain (when it rains), and can increase the likelihood of hailstorms. There are also extreme weather patterns that become more common when it gets colder. While tropical storms and hurricanes increase in frequency in hot weather, more laminar storms ("winter gales") get more common when the weather is colder. I believe this is because the LACK of turbulence/chaos means there are fewer factors that can break up such storms. This last type is common in places like Canada, Scandinavia or Siberia now, and come almost exclusively during winter. Btw, the impact of increased temperature on weather is something that we can already observe on Earth today, simply by travelling between different weather zones. While SOME of the extra energy can affect areas far away from where the heating occurs, a lot of the effects are local or regional. That means that it's likely that Temperate Zone type weather is going to shift a bit to the North, and include a greater proportion of Canada, Scandinavia and Russia. These areas will then get weather more similar to places like the US/German/China today. The southern parts of the temperate zone is likely to see weather patterns that resemble tropical (or desert) weather zones. Much of the US can be more like Mexico, France can be more like Morocco or Greece, Sothern China more like Thailand, and so on. This means that areas that get warmer AND dryer (like Spain, Italy and France, probably) will get some of the variations currently seen in Sahara. But it doesn't mean that the temperature fluctuations get greater everywhere. Some areas become more humid, and that means lower fluctuations. Btw, for humans, dryer weather can be an advantage, since it allows us to dissipate heat much more easily. For farming it's less ideal. Places like Saudi Arabia could go in the opposite direction, with higher humidity and more rain, farming could become easier, but the risk of wet bulbs could also go up. Anyway, while it is true that more energy in the atmosphere ON average increases the frequency of most types of extreme weather, it is not true that it will increase all types of extreme weather everywhere. EDIT: Here's a map: https://archive.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-3-2-3.html https://archive.ipcc.ch/publications_and_data/ar4/wg1/en/ch1...
mrguyorama 2y ago
"5C warmer" doesn't mean a uniform increase in temperature of 5 degrees at all times. It means "5 * the thermal mass of the earth's biosphere" worth of extra energy in an extremely chaotic system that is currently in a local stable point, but doesn't have to stay there.
- trashtester 2y ago
  A 5C warming is indeed likely to make a few areas uninhabitable. I'm not saying climate change is not a problem. I'm just saying it's not an extinction event. But keep in mind that the areas that tend to get the greatest warming tend to be the dry ones. In such places, sweating will still allow human bodies to regulate body heat, if air conditioning breaks down.
  - mrexroad 2y ago
    I think you missed the above comment’s point about risk to stability in a chaotic system…
    - trashtester 2y ago
      That part looked like gibberish.... Maybe rewrite to make it more clear?
      - mrexroad 2y ago
        Stability in a chaotic system is precarious. Changes, even if small or seemingly trivial, can cause massive cascading effects from positive/negative feedback loops. Sigh, I don’t mean to sound like a dick, but if that’s gibberish then you might want to strengthen some of the foundational understandings around systems.
        trashtester 2y ago
        I'm familiar with chaos theory, and not rejecting issues related to chaotic systems. But this part doesn't really seem well formed: > It means "5 * the thermal mass of the earth's biosphere" worth of extra energy Here it seems that the units were missing, at best. The extra energy would be "5K * the heat capacity of the biosphere (in J/K)" > in an extremely chaotic system that is currently in a local stable point, but doesn't have to stay there. First of all, I don't think the current state is THAT stable. And when it comes to any disturbance to the stability caused by the extra energy, that's what we have climate scientists for. Specifically, those are the ones that need to assign specific probabilities to the varous scenarios available. For instance, while it is POSSIBLE that a result of the chaotic dynamics of the system would be that the Gulf Stream got reversed, it seems that the curren consensus is that this is highly unlikely. However, there are a lot of other effects that would be highly likely, such as an increased rate of hurricanes for instance. But hurricanes is not a state of the whole system, it's basically just a type of weather that gets more common. So, maybe "gibberish" was not the perfect word to describe it, as I was able to parse it. It's just that it didn't say anything specific. It was more at the level "It's getting chaotic, and chaos is scary", without making any specific predictions or producing references.

goatlover 2y ago

Source for these claims?