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Your comment may sound unrelated - but it's exactly at the heart of the problem. Both climate change and viral growth increase exponentially. Not only do we re

Your comment may sound unrelated - but it's exactly at the heart of the problem. Both climate change and viral growth increase exponentially. Not only do we release more CO2 into the atmosphere every year, but also the growth rate accelerates.

potatoman22 5y ago
Why does climate change increase exponentially? For reasons other than our collective output increasing exponentially?
- deleted 5y ago
  [deleted]
- Diederich 5y ago
  > Why does climate change increase exponentially? For reasons other than our collective output increasing exponentially? I'm a decades long 'climate change alarmist'. We really don't know if the temperature is really increasing exponentially, considering the proper definition of exponential: "a value increases in proportion to its current value". Also consider that "exponential growth" doesn't necessarily mean "extremely fast"...at least in reasonable time horizons. I and many others think that the amount of energy in our planet's atmosphere is increasing, and we also believe the rate of increase is increasing. This might be technically 'exponential', but it very well might not. It could 'just' be quadratic...which, given the 'right' constants, could be even worse. > For reasons other than our collective output increasing exponentially? Humanity's greenhouse gas output was growing (something like) exponentially (ie, 'very fast') for a good while, but it's probably no longer: https://ourworldindata.org/grapher/annual-co-emissions-by-region https://ourworldindata.org/grapher/annual-co-emissions-by-re... To your underlying, fundamental question: why is the rate of increase probably increasing? Feedback effects. To seriously get into the weeds, look here: https://en.wikipedia.org/wiki/Climate_change_feedback https://en.wikipedia.org/wiki/Climate_change_feedback In short, all chaotic but meta-stable systems, such as our planet's climate, have built in many 'tipping points', where a small change in input can have a very large change in behaviour. Under ideal circumstances, such tipping points are quite hard to identify with any precision, and virtually impossible with the most complex system in the world: earth's climate. Even shorter: we don't know for certain, but there's a large and ever growing pile of data that shows here and now impacts of a warming climate. Per my other comment, for example: the rate at which 100, 500 and 1000 year extreme weather events are occurring. In summary: us not knowing with certainty does NOT mean we should not make it a top priority to start reversing the things we do know are causing damage: enormous releases of CO2 and CH4.
  - potatoman22 5y ago
    Thanks!
- addison-lee 5y ago
  From what I understand it is feedback loops that cause concern for exponential climate change. For example, snow reflects a large amount of the sun’s energy back into space. As you lose the snow cover you absorb more heat causing more snow to melt, leading to snow melting faster, etc. etc. Another example is in the Arctic tundra. The top layer of the ground was always frozen, i.e. a permafrost. However now that layer is melting and it releases a ton of methane. Methane causes the temperatures to rise, leading to the permafrost melting faster and more methane being released.
- SAI_Peregrinus 5y ago
  Positive feedback loops. For example, warming the climate tends to melt ice. Ice reflects sunlight back to space better than liquid water or dirt. So the reduced ice cover makes more sunlight get absorbed by the Earth. Absorbed sunlight becomes heat, which raises the temperature. The increased temperature melts more ice. Technically all of these loops can only result in a sigmoid curve, not an exponential. The temperature won't become arbitrarily large. Trivially it can't get any hotter than the input (the sun). But in the ranges we care about (temperatures suitable for human habitation without massive adaptation and migration needed) it's effectively exponential.
  - Pyramus 5y ago
    Technically logistic growth is locally exponential until it isn't.
    - SAI_Peregrinus 5y ago
      Yes, that's what I mean when I say it's effectively exponential in the ranges we care about. It's effectively indistinguishable from exponential growth (locally).
- MarkLowenstein 5y ago
  This is an excellent question. It is a very popular idea that there is some "tipping point", plus positive feedback loops, that are definitely going to make this problem worse, someday. That they are popularly imagined by non-scientists, and that the effects are always promised for the future rather than identified in the past, are cause for skepticism. Judging by the fact that for the billion years after life has dominated, Earth climate has always stayed decidedly non-Martian and non-Venusian, the evidence is strong that negative feedback loops are more powerful than the positive ones that people may publicize. I would like to see more substantiation behind such assertions.
deleted 5y ago
[deleted]
zosima 5y ago
No, the effect of a linear increase of CO2 on temperature is logarithmic. Though the speculation is the there will be catastrophic exponential feedback mechanisms. I guess CO2 is increasing exponentially, so maybe CO2-dependent temperature change is a somewhat linear with respect to time.

potatoman22 5y ago

Why does climate change increase exponentially? For reasons other than our collective output increasing exponentially?

deleted 5y ago
[deleted]
Diederich 5y ago
> Why does climate change increase exponentially? For reasons other than our collective output increasing exponentially? I'm a decades long 'climate change alarmist'. We really don't know if the temperature is really increasing exponentially, considering the proper definition of exponential: "a value increases in proportion to its current value". Also consider that "exponential growth" doesn't necessarily mean "extremely fast"...at least in reasonable time horizons. I and many others think that the amount of energy in our planet's atmosphere is increasing, and we also believe the rate of increase is increasing. This might be technically 'exponential', but it very well might not. It could 'just' be quadratic...which, given the 'right' constants, could be even worse. > For reasons other than our collective output increasing exponentially? Humanity's greenhouse gas output was growing (something like) exponentially (ie, 'very fast') for a good while, but it's probably no longer: https://ourworldindata.org/grapher/annual-co-emissions-by-region https://ourworldindata.org/grapher/annual-co-emissions-by-re... To your underlying, fundamental question: why is the rate of increase probably increasing? Feedback effects. To seriously get into the weeds, look here: https://en.wikipedia.org/wiki/Climate_change_feedback https://en.wikipedia.org/wiki/Climate_change_feedback In short, all chaotic but meta-stable systems, such as our planet's climate, have built in many 'tipping points', where a small change in input can have a very large change in behaviour. Under ideal circumstances, such tipping points are quite hard to identify with any precision, and virtually impossible with the most complex system in the world: earth's climate. Even shorter: we don't know for certain, but there's a large and ever growing pile of data that shows here and now impacts of a warming climate. Per my other comment, for example: the rate at which 100, 500 and 1000 year extreme weather events are occurring. In summary: us not knowing with certainty does NOT mean we should not make it a top priority to start reversing the things we do know are causing damage: enormous releases of CO2 and CH4.
- potatoman22 5y ago
  Thanks!
addison-lee 5y ago
From what I understand it is feedback loops that cause concern for exponential climate change. For example, snow reflects a large amount of the sun’s energy back into space. As you lose the snow cover you absorb more heat causing more snow to melt, leading to snow melting faster, etc. etc. Another example is in the Arctic tundra. The top layer of the ground was always frozen, i.e. a permafrost. However now that layer is melting and it releases a ton of methane. Methane causes the temperatures to rise, leading to the permafrost melting faster and more methane being released.
SAI_Peregrinus 5y ago
Positive feedback loops. For example, warming the climate tends to melt ice. Ice reflects sunlight back to space better than liquid water or dirt. So the reduced ice cover makes more sunlight get absorbed by the Earth. Absorbed sunlight becomes heat, which raises the temperature. The increased temperature melts more ice. Technically all of these loops can only result in a sigmoid curve, not an exponential. The temperature won't become arbitrarily large. Trivially it can't get any hotter than the input (the sun). But in the ranges we care about (temperatures suitable for human habitation without massive adaptation and migration needed) it's effectively exponential.
- Pyramus 5y ago
  Technically logistic growth is locally exponential until it isn't.
  - SAI_Peregrinus 5y ago
    Yes, that's what I mean when I say it's effectively exponential in the ranges we care about. It's effectively indistinguishable from exponential growth (locally).
MarkLowenstein 5y ago
This is an excellent question. It is a very popular idea that there is some "tipping point", plus positive feedback loops, that are definitely going to make this problem worse, someday. That they are popularly imagined by non-scientists, and that the effects are always promised for the future rather than identified in the past, are cause for skepticism. Judging by the fact that for the billion years after life has dominated, Earth climate has always stayed decidedly non-Martian and non-Venusian, the evidence is strong that negative feedback loops are more powerful than the positive ones that people may publicize. I would like to see more substantiation behind such assertions.

deleted 5y ago

[deleted]

zosima 5y ago

No, the effect of a linear increase of CO2 on temperature is logarithmic. Though the speculation is the there will be catastrophic exponential feedback mechanisms. I guess CO2 is increasing exponentially, so maybe CO2-dependent temperature change is a somewhat linear with respect to time.