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Given long enough to adapt (perhaps a million years? Perhaps two million?) then there would be no negative effects to the current changes. The dangers are entir

Given long enough to adapt (perhaps a million years? Perhaps two million?) then there would be no negative effects to the current changes. The dangers are entirely to do with the speed of the current change. The increasing acidity of the oceans will, over the next two centuries, lead to a mass extinction in the oceans which could eventually have large effects on the gases that make up our atmosphere -- and here we need to concern ourselves with black swan events, which will remain unlikely, even 200 years from now, but which, if they were to occur, would lead to an extinction so broad that it would threaten human survival.

georgewsinger 5y ago
As pointed above, there is also human survival tail risk to stopping global warming. How are you so certain to know which tail risk is larger, or likelier?
- BlueTemplar 5y ago
  Humans have already lived through several glaciations. But we weren't even around yet when the current ice age started 4M years ago.
- lkrubner 5y ago
  I don't think you read what I wrote. I never mentioned global warming. If we continue at current rates of fossil fuel use for another 200 years, the acidification of the ocean will start to endanger phytoplankton, which makes much of the oxygen we breathe. The loss of phytoplankton drove the most serious mass extinction in the Earth's history: https://earthsky.org/earth/ocean-acidification-drove-earths-largest-mass-extinction/ https://earthsky.org/earth/ocean-acidification-drove-earths-... The article that started this thread on Hacker News suggested that the death rate goes up 10% in the winter, which gives some sense of what the tail risk is from cold weather. By contrast, the tail risk from the acidification of the oceans is something like the Permian/Triassic mass extinction. You ask "How are you so certain to know which tail risk is larger, or likelier?" We can be certain because one risk is many orders of magnitude worse than the other.
  - georgewsinger 5y ago
    I don't think you read what I wrote. The tail risk I was speaking of was not a winter death rate increasing by 10%, but the risk of us receding into a deeper ice age over the next several centuries. The extinction event you're referring to was hypothesized by these researchers to have come from volcanic erruptions:[1] > During the eruptions, huge amounts of carbon dioxide and molten rock burst through the Earth's crust, burning through coal and limestone, and releasing carbon dioxide into the atmosphere. That made oceans and rainwater more acidic, and dissolved more calcium from rocks into the ocean. So far, so analogous. But does it seem like you might be exaggerating a tad by comparing human fossil fuel usage to this level of carbon release? > Payne calculated that the eruptions, which lasted upward of a million years, released 13,000 to 43,000 gigatons (1 gigaton equals 1 billion tons) of carbon in the atmosphere. By comparison, scientists estimate we would release an estimated 5,000 gigatons of carbon if we used up all the fossil fuels in the Earth. AFAIK, we aren't even at 50% usage over the past 150 years. We can also check this theory against long-term carbon PPM charts, which show at various points in earth's history significantly more carbon concentration then either now or even 250 million years ago.[2] In any event, the researcher admits himself that the tail risk is not directly comparable to the Permian/Triassic mass extinction (though it's still an important consideration): > Payne said humans may not ultimately release as much carbon dioxide as the Siberian Traps, but we may be doing it at a faster rate. "We won't necessarily end up with a world that looks as bad as it did after the end-Permian extinction, but that event highlights the fact that things can go very, very wrong," Payne said. In any event, I think you have a point (in fact I think you've made the best point of all of the responses), but you've exaggerated it to make it as if it's the dominant risk factor in the net calculation as to whether global warming is long-term harmful or beneficial. I don't think this is so clear. Acting as if our current levels of fossil fuel usage is going to lead to a mass extinction comparable to the end of the Permian/Triassic era comes off as alarmist and motivated. [1] https://news.stanford.edu/news/2010/april/prehistoric-mass-extinction-042710.html https://news.stanford.edu/news/2010/april/prehistoric-mass-e... [2] The way to extend this conversation productively would be to estimate the rate at which these volcanic eruptions were dumping CO2 in the air and compare it to the rate at which we are.
    - 5y ago

georgewsinger 5y ago

As pointed above, there is also human survival tail risk to stopping global warming. How are you so certain to know which tail risk is larger, or likelier?

BlueTemplar 5y ago
Humans have already lived through several glaciations. But we weren't even around yet when the current ice age started 4M years ago.
lkrubner 5y ago
I don't think you read what I wrote. I never mentioned global warming. If we continue at current rates of fossil fuel use for another 200 years, the acidification of the ocean will start to endanger phytoplankton, which makes much of the oxygen we breathe. The loss of phytoplankton drove the most serious mass extinction in the Earth's history: https://earthsky.org/earth/ocean-acidification-drove-earths-largest-mass-extinction/ https://earthsky.org/earth/ocean-acidification-drove-earths-... The article that started this thread on Hacker News suggested that the death rate goes up 10% in the winter, which gives some sense of what the tail risk is from cold weather. By contrast, the tail risk from the acidification of the oceans is something like the Permian/Triassic mass extinction. You ask "How are you so certain to know which tail risk is larger, or likelier?" We can be certain because one risk is many orders of magnitude worse than the other.
- georgewsinger 5y ago
  I don't think you read what I wrote. The tail risk I was speaking of was not a winter death rate increasing by 10%, but the risk of us receding into a deeper ice age over the next several centuries. The extinction event you're referring to was hypothesized by these researchers to have come from volcanic erruptions:[1] > During the eruptions, huge amounts of carbon dioxide and molten rock burst through the Earth's crust, burning through coal and limestone, and releasing carbon dioxide into the atmosphere. That made oceans and rainwater more acidic, and dissolved more calcium from rocks into the ocean. So far, so analogous. But does it seem like you might be exaggerating a tad by comparing human fossil fuel usage to this level of carbon release? > Payne calculated that the eruptions, which lasted upward of a million years, released 13,000 to 43,000 gigatons (1 gigaton equals 1 billion tons) of carbon in the atmosphere. By comparison, scientists estimate we would release an estimated 5,000 gigatons of carbon if we used up all the fossil fuels in the Earth. AFAIK, we aren't even at 50% usage over the past 150 years. We can also check this theory against long-term carbon PPM charts, which show at various points in earth's history significantly more carbon concentration then either now or even 250 million years ago.[2] In any event, the researcher admits himself that the tail risk is not directly comparable to the Permian/Triassic mass extinction (though it's still an important consideration): > Payne said humans may not ultimately release as much carbon dioxide as the Siberian Traps, but we may be doing it at a faster rate. "We won't necessarily end up with a world that looks as bad as it did after the end-Permian extinction, but that event highlights the fact that things can go very, very wrong," Payne said. In any event, I think you have a point (in fact I think you've made the best point of all of the responses), but you've exaggerated it to make it as if it's the dominant risk factor in the net calculation as to whether global warming is long-term harmful or beneficial. I don't think this is so clear. Acting as if our current levels of fossil fuel usage is going to lead to a mass extinction comparable to the end of the Permian/Triassic era comes off as alarmist and motivated. [1] https://news.stanford.edu/news/2010/april/prehistoric-mass-extinction-042710.html https://news.stanford.edu/news/2010/april/prehistoric-mass-e... [2] The way to extend this conversation productively would be to estimate the rate at which these volcanic eruptions were dumping CO2 in the air and compare it to the rate at which we are.
  - 5y ago