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No, it certainly isn't beyond dispute that more CO₂ is significant and bad. Some example arguments: (1) The Earth has been cooler with CO₂ levels 10 times high

No, it certainly isn't beyond dispute that more CO₂ is significant and bad. Some example arguments: (1) The Earth has been cooler with CO₂ levels 10 times higher. We currently have some of the lowest levels in the history of the planet. (2) CO₂ increases and decreases also usually seem to trail temperature changes. (3) Warmer temperatures are not necessarily negative. We've been in an ice age for 2 million years, but life thrived at higher temps. (4) You have to balance negative effects with positive effects, like increased greening.

suture 4y ago
It is, I believe, beyond dispute that CO2 has heat trapping effects. All else remaining the same, increasing CO2 increases the heat. That at another time there was higher CO2 levels with lower heat merely means that not all else remained the same.
- prometheus76 4y ago
  You just ignored all of the challenges to your current worldview. Cognitive dissonance is just as difficult for the people you are trying to convince as it appears to be for you.
  - suture 4y ago
    I did no such thing. Increasing carbon dioxide, keeping all else equal, traps more heat. This isn’t disputable. Hence my refusal to say otherwise can’t possibly be cognitive dissonance. It might be a good thing to increase CO2. It might be bad. It might be the case that increasing carbon dioxide causes counter balancing effects and therefore increasing CO2 does not increase temperature (I remain skeptical of this but I’m not a climate scientist). But what is beyond dispute is that massively increasing CO2 will cause climatic disruptions while the weather system reaches a new equilibrium.
    - JumpCrisscross 4y ago
      > keeping all else equal The reasonable pushback against this is per se isn't a realistic assumption in a system as dynamic as our biosphere.
      - suture 4y ago
        Oh definitely. But it seems to me that it is obvious that increases in CO2 on a massive, rapid scale will necessitate climatic changes (not necessarily bad) as the system finds a new equilibrium. This may in turn cause massive disruptions to human societies. Note that there are many seemingly obvious things that are false so I could be wrong.
        native_samples 4y ago
        "This may in turn cause massive disruptions to human societies." The word "may" is doing a lot of work here. Lots of things may cause massive disruptions to human society. One thing we can say with certainty: the mitigation efforts being proposed to reduce CO2 levels will cause massive disruptions to human society.
- graycat 4y ago
  - suture 4y ago
    Like, wonder of wonders, by killing people and pouring their blood on a rock, the Mayans were successful, fantastic, amazing, keeping the sun moving across the sky!!! The next time I teach correlation/causation I’m using this as my goto example.
    - graycat 4y ago
      For a reference, as of Wednesday, May 6th, 2009 at http://books.google.com/books?id=DgqLplWtGPgC&pg=PA76&lpg=PA76&dq=Mayan+blood+sun+moving+sacrifice&source=web&ots=Do6njWN5M9&sig=FxTeclIiqggqIH5Ws_oENCek1uI&hl=en&sa=X&oi=book_result&resnum=1&ct=result#PPA76,M1 http://books.google.com/books?id=DgqLplWtGPgC&pg=PA76&lpg=PA... (but not now, no longer) from page 76 of Susan Milbrath, Star Gods of the Maya: Astronomy in Art, Folklore, and Calendars (The Linda Schele Series in Maya and Pre-Columbian Studies), ISBN-13 978-0292752269, University of Texas Press, 2000. with "Indeed, blood sacrifice is required for the sun to move, according to Aztec cosmology (Durian 1971:179; Sahaguin 1950 - 1982, 7:8)."
  - snowwrestler 4y ago
    To answer your chemistry question, once a molecule of CO2 absorbs infrared light, it then emits infrared light. On average it’s in a random direction, so some goes out into space eventually. But some goes straight toward the Earth’s surface, which also absorbs and then re-emits it. The result is that some IR energy is trapped bouncing back and forth between the surface and atmospheric greenhouse gases (there are a few, not just CO2). This is the so-called “greenhouse effect” that keeps the surface habitable. As you increase the amount of greenhouse gases, there are more molecules available to absorb and re-emit IR energy. So the total amount of energy that can be trapped bouncing back and forth goes up. More heat is trapped. CO2 is particularly worrisome because the carbon cycle is slow. Water vapor has a larger effect, but it varies on the order of weeks (when it rains, for example). CO2 can take hundreds of years to get fixed again once it is in the atmosphere.
arethuza 4y ago
There were also events like the PETM with a 5C to 8C increase: https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Thermal_Maximum https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Therm...
snowwrestler 4y ago
1) If insolation falls, global temps can be lower even with more greenhouse gases in the atmosphere. If insolation stays constant, increasing greenhouse gases will increase the amount of energy trapped under the atmosphere (aka heat). Insolation varies slowly based on orbital variations, which created the historical record you’re referencing. Right now we don’t have any evidence that insolation is declining fast enough to offset the effect of the greenhouse gases we are adding to our atmosphere. Which makes sense because we independently measure an upward trend in heat trapped in the atmosphere. 2) In the global historical record the peak of CO2 has usually trailed the peak of temperature. Again this reflects changes in insolation: as more sunlight makes the climate get hotter, more CO2 is released. Then as sunlight declines, the climate cools but the CO2 lingers for a while. This is actually really concerning because it implies that we should expect a natural spike of CO2 on top of our anthropogenic spike of CO2, meaning it will get much worse than it even looks now. 3) Yes, “life” can thrive at higher temps, but our bodies, culture, and infrastructure are adapted for these temps. And it’s not just temperature; sea level rise (primarily driven by the metric expansion of water as it is heated) will inundate large amounts of livable land including some of the most productive and populated. Maybe good for neritic life, but bad for us. 4) The negative and positive effects don’t necessarily balance. Again, losing dry land to the sea is not balanced by increased ocean algal growth. “I destroyed your house, but gave you more fertilizer for your lawn”—does that seem like a fair trade?

suture 4y ago

It is, I believe, beyond dispute that CO2 has heat trapping effects. All else remaining the same, increasing CO2 increases the heat. That at another time there was higher CO2 levels with lower heat merely means that not all else remained the same.

prometheus76 4y ago
You just ignored all of the challenges to your current worldview. Cognitive dissonance is just as difficult for the people you are trying to convince as it appears to be for you.
- suture 4y ago
  I did no such thing. Increasing carbon dioxide, keeping all else equal, traps more heat. This isn’t disputable. Hence my refusal to say otherwise can’t possibly be cognitive dissonance. It might be a good thing to increase CO2. It might be bad. It might be the case that increasing carbon dioxide causes counter balancing effects and therefore increasing CO2 does not increase temperature (I remain skeptical of this but I’m not a climate scientist). But what is beyond dispute is that massively increasing CO2 will cause climatic disruptions while the weather system reaches a new equilibrium.
  - JumpCrisscross 4y ago
    > keeping all else equal The reasonable pushback against this is per se isn't a realistic assumption in a system as dynamic as our biosphere.
    - suture 4y ago
      Oh definitely. But it seems to me that it is obvious that increases in CO2 on a massive, rapid scale will necessitate climatic changes (not necessarily bad) as the system finds a new equilibrium. This may in turn cause massive disruptions to human societies. Note that there are many seemingly obvious things that are false so I could be wrong.
      - native_samples 4y ago
        "This may in turn cause massive disruptions to human societies." The word "may" is doing a lot of work here. Lots of things may cause massive disruptions to human society. One thing we can say with certainty: the mitigation efforts being proposed to reduce CO2 levels will cause massive disruptions to human society.
graycat 4y ago
- suture 4y ago
  Like, wonder of wonders, by killing people and pouring their blood on a rock, the Mayans were successful, fantastic, amazing, keeping the sun moving across the sky!!! The next time I teach correlation/causation I’m using this as my goto example.
  - graycat 4y ago
    For a reference, as of Wednesday, May 6th, 2009 at http://books.google.com/books?id=DgqLplWtGPgC&pg=PA76&lpg=PA76&dq=Mayan+blood+sun+moving+sacrifice&source=web&ots=Do6njWN5M9&sig=FxTeclIiqggqIH5Ws_oENCek1uI&hl=en&sa=X&oi=book_result&resnum=1&ct=result#PPA76,M1 http://books.google.com/books?id=DgqLplWtGPgC&pg=PA76&lpg=PA... (but not now, no longer) from page 76 of Susan Milbrath, Star Gods of the Maya: Astronomy in Art, Folklore, and Calendars (The Linda Schele Series in Maya and Pre-Columbian Studies), ISBN-13 978-0292752269, University of Texas Press, 2000. with "Indeed, blood sacrifice is required for the sun to move, according to Aztec cosmology (Durian 1971:179; Sahaguin 1950 - 1982, 7:8)."
- snowwrestler 4y ago
  To answer your chemistry question, once a molecule of CO2 absorbs infrared light, it then emits infrared light. On average it’s in a random direction, so some goes out into space eventually. But some goes straight toward the Earth’s surface, which also absorbs and then re-emits it. The result is that some IR energy is trapped bouncing back and forth between the surface and atmospheric greenhouse gases (there are a few, not just CO2). This is the so-called “greenhouse effect” that keeps the surface habitable. As you increase the amount of greenhouse gases, there are more molecules available to absorb and re-emit IR energy. So the total amount of energy that can be trapped bouncing back and forth goes up. More heat is trapped. CO2 is particularly worrisome because the carbon cycle is slow. Water vapor has a larger effect, but it varies on the order of weeks (when it rains, for example). CO2 can take hundreds of years to get fixed again once it is in the atmosphere.

arethuza 4y ago

There were also events like the PETM with a 5C to 8C increase: https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Thermal_Maximum https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Therm...

snowwrestler 4y ago

1) If insolation falls, global temps can be lower even with more greenhouse gases in the atmosphere. If insolation stays constant, increasing greenhouse gases will increase the amount of energy trapped under the atmosphere (aka heat). Insolation varies slowly based on orbital variations, which created the historical record you’re referencing. Right now we don’t have any evidence that insolation is declining fast enough to offset the effect of the greenhouse gases we are adding to our atmosphere. Which makes sense because we independently measure an upward trend in heat trapped in the atmosphere. 2) In the global historical record the peak of CO2 has usually trailed the peak of temperature. Again this reflects changes in insolation: as more sunlight makes the climate get hotter, more CO2 is released. Then as sunlight declines, the climate cools but the CO2 lingers for a while. This is actually really concerning because it implies that we should expect a natural spike of CO2 on top of our anthropogenic spike of CO2, meaning it will get much worse than it even looks now. 3) Yes, “life” can thrive at higher temps, but our bodies, culture, and infrastructure are adapted for these temps. And it’s not just temperature; sea level rise (primarily driven by the metric expansion of water as it is heated) will inundate large amounts of livable land including some of the most productive and populated. Maybe good for neritic life, but bad for us. 4) The negative and positive effects don’t necessarily balance. Again, losing dry land to the sea is not balanced by increased ocean algal growth. “I destroyed your house, but gave you more fertilizer for your lawn”—does that seem like a fair trade?