Global Warming and the Precautionary Principle

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Discussion Overview

The discussion centers around the relationship between global warming and human contributions to CO2 emissions, particularly in the context of the precautionary principle. Participants explore the implications of fossil carbon release, historical atmospheric composition, and the potential consequences of global warming, while debating the validity of various claims and models.

Discussion Character

  • Debate/contested
  • Exploratory
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants assert that fossil carbon is being introduced into the biosphere by humans, while others contest the certainty of historical atmospheric composition.
  • There is a suggestion that the consequences of global warming are not definitively established and depend on various conditions, including the extent of temperature increase.
  • Concerns are raised about the reliability of climate models and predictions, with some participants arguing that they are based on uncertain assumptions and incomplete data.
  • Some participants propose that exercising caution in limiting CO2 emissions is reasonable, even if the likelihood of severe consequences is debated.
  • There is a discussion about the origins of carbon in fossil fuels and the implications of high CO2 levels in the past, with calls for alternative explanations if current assumptions are contestable.
  • The analogy of passing on a hill is used to illustrate uncertainty in predicting climate outcomes, with some participants expressing skepticism about the certainty of impending dangers.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the causes and consequences of global warming, with multiple competing views and significant disagreement on the validity of claims regarding atmospheric history and the implications of CO2 emissions.

Contextual Notes

The discussion highlights limitations in the understanding of atmospheric evolution and the complexity of climate science, with participants acknowledging the challenges in reaching definitive conclusions based on current knowledge.

Andrew Mason
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Let's suppose that, as many of the posters here believe, there is a good possibility that global warming is not priimarily caused or even signficantly contributed to by human CO2 emissions. Let's suppose that there is a very good possibility also that CO2 concentrations are not signficantly higher than they were a 100 years ago.

What seems to me to be incontestible is that fossil carbon is being brought into the biosphere by humans. It is also incontestible that much of this carbon was deposited by plants that grew in an atmosphere much richer in CO2 and much less rich in O2.

Given the consequences for life on Earth of global warming, is it not reasonable to be cautious and limit CO2 emissions as much as possible even if there is a good chance it is not occurring?

I don't pass going up hills. It is not because I am sure there is something coming. There seldom is. I exercise reasonable precaution because I don't really know.

AM
 
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Andrew Mason said:
(snip)What seems to me to be incontestible is that fossil carbon is being brought into the biosphere by humans. It is also incontestible that much of this carbon was deposited by plants that grew in an atmosphere much richer in CO2 and much less rich in O2.

The history of atmospheric composition is contestible.

Given the consequences for life on Earth of global warming, is it not reasonable to be cautious and limit CO2 emissions as much as possible even if there is a good chance it is not occurring?

The "consequences" aren't "given." Dire consequences have been postulated, based on "Rube Goldberg" concatenations of "if" statements.

I don't pass going up hills. It is not because I am sure there is something coming. There seldom is. I exercise reasonable precaution because I don't really know.

You are certain that the opposite lane is reserved for oncoming traffic, and that there is oncoming traffic. It is likewise certain that atmospheric CO2 levels are not driven by climate models, but by physical principles.
 
Bystander said:
The history of atmospheric composition is contestible.

So where, in your theory, did the carbon come from to make the coal, oil and gas, limestone, etc. that is in the earth?

The "consequences" aren't "given." Dire consequences have been postulated, based on "Rube Goldberg" concatenations of "if" statements.
It depends on how much global warming we get. Are you suggesting that an increase of 10 degrees C is not serious? The point I am making is not that the consequences are certain, but that the possible consequences will have a serious negative impact on the Earth - and we only have one planet that is fit for life.
You are certain that the opposite lane is reserved for oncoming traffic, and that there is oncoming traffic. It is likewise certain that atmospheric CO2 levels are not driven by climate models, but by physical principles.
The point is that I am not certain there is oncoming traffic. Even on a lonely country road, I stick to my lane going up a hill.

The problem here is that it is very complicated If scientists cannot agree on the result of increased CO2 in the atmosphere, it does not seem reasonable to pick the best case scenario.

AM
 
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Andrew Mason said:
So where, in your theory, did the carbon come from to make the coal, oil and gas, limestone, etc. that is in the earth?

"My theory?" You assert incontestible knowledge of the history of carbon dioxide and oxygen concentrations in the atmosphere, and I point out to you that it is contestible, and now "I've got a theory?" Are you referring to your "Sequestration" thread? In which case, it's not where the carbon came from, but where the oxygen came from and where all the carbon went.

It depends on how much global warming we get. Are you suggesting that an increase of 10 degrees C is not serious? The point I am making is not that the consequences are certain, but that the possible consequences will have a serious negative impact on the Earth - and we only have one planet that is fit for life.

It's also possible that the pink elephants from Pluto will be landing tomorrow to kick us off the planet. Once a half dozen half-baked models have been strung together, the predictions aren't worth worrying about.

The point is that I am not certain there is oncoming traffic. Even on a lonely country road, I stick to my lane going up a hill.

The point is that you are ABSOLUTELY certain there is oncoming traffic, and that you have absolutely no idea where it is. The analogy between passing on hills and climate is lousy. You know climate changes. You also know that you haven't a clue what drives those changes in what directions.

The problem here is that it is very complicated If scientists cannot agree on the result of increased CO2 in the atmosphere, it does not seem reasonable to pick the best case scenario.

All science is done on "worst case" assumptions: there are always mistakes in the observations, data reduction, and interpretation of results. As a consequence, one does NOT leap to conclusions about z-rays, Piltdown man, polywater, space charge in electrolytes, cold fusion, or any number of other much ballyhooed results. One reviews theory, methods, results, interpretations, and conclusions.
 
Bystander said:
"My theory?" You assert incontestible knowledge of the history of carbon dioxide and oxygen concentrations in the atmosphere, and I point out to you that it is contestible, and now "I've got a theory?" Are you referring to your "Sequestration" thread? In which case, it's not where the carbon came from, but where the oxygen came from and where all the carbon went.
I merely observed that there was a lot of carbon in the Earth that was once living at or near the surface of the earth. I was not aware there was some other explanation for it other than high levels of CO2 in the atmosphere. If you are saying that is contestible, I would like to hear another explanation.
It's also possible that the pink elephants from Pluto will be landing tomorrow to kick us off the planet. Once a half dozen half-baked models have been strung together, the predictions aren't worth worrying about.
The predictions are based on a rational analysis of, albeit incomplete, data. But that does not mean they are wrong. We don't need proof beyond a reasonable doubt here. Not every earthquake leads to a tsunami, but after an earthquake I am not going to head for the beach.

The point is that you are ABSOLUTELY certain there is oncoming traffic, and that you have absolutely no idea where it is.
There may not be another car on the road at all. I don't know if there is traffic. I am not going to take the chance.

All science is done on "worst case" assumptions: there are always mistakes in the observations, data reduction, and interpretation of results. As a consequence, one does NOT leap to conclusions about z-rays, Piltdown man, polywater, space charge in electrolytes, cold fusion, or any number of other much ballyhooed results. One reviews theory, methods, results, interpretations, and conclusions.
But you are leaping to conclusions: that there is no danger that we ought to be cautious about.

AM
 
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Andrew Mason said:
I merely observed that there was a lot of carbon in the Earth that was once living at or near the surface of the earth. I was not aware there was some other explanation for it other than high levels of CO2 in the atmosphere. If you are saying that is contestible, I would like to hear another explanation.

The origins and evolution of the Earth's atmosphere are wide open for speculation. Hit the textbooks and journals --- stay away from TLC, Disc. and Hist. Ch..

The predictions are based on a rational analysis of, albeit incomplete, data. But that does not mean they are wrong. We don't need proof beyond a reasonable doubt here. Not every earthquake leads to a tsunami, but after an earthquake I am not going to head for the beach.

Every earthquake does lead to a tsunami. That's physics. Not every earthquake is well enough coupled to the oceans to produce a large tsunami. That's why the networks of tsunami monitoring instruments have been established in various places around the world --- to cover the gap between theory and practice. The geophysicists know their theoretical foundations and models are garbage, and have taken the appropriate measures.

There may not be another car on the road at all. I don't know if there is traffic. I am not going to take the chance.

You constructed a lousy analogy --- give it up. You KNOW there are other vehicles on the road. You know you are not in control of them. You know you have no clue where they are.

But you are leaping to conclusions: that there is no danger that we ought to be cautious about.

No, I am not leaping to any such conclusion. There is NOT sufficient data to reach any conclusion. If you wish to take precautions against every monster in the closet, pink elephant from Pluto, angry god, collapsible dam, fallible levee, possible tire failure, potential lightning strike, tornado, meteor, mudslide, pyroclastic flow, sinkhole collapse, locust plague, and whatever else you choose to fret about, do so. Don't expect the world to follow suit.
 

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