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These [1] are the ice core data from the past ~400k years. Not only has the temperature gotten substantially hotter before, but this cycle of rising and lowerin

These [1] are the ice core data from the past ~400k years. Not only has the temperature gotten substantially hotter before, but this cycle of rising and lowering global temperatures has been happening before humans even existed. And these are not small temperature deviations. The range between the lows and the highs is around 9 degrees celsius. I don't entirely understand why people are so averse to these data. Do people think they're just fake or something? This does not mean that humanity is not contributing to the current warming trend. But the data show beyond any doubt that warming cycles do, and would happen, even if humanity did not exist. There were not periods where 'over a few years we saw a bit of warming' - there have been centuries of major warming that increased the ambient temperature of the Earth by ~9 degrees celcius. The most recent warmining cycle, before the one we're currently in, lasted some 20,000 years. [1] - https://upload.wikimedia.org/wikipedia/commons/f/f8/Ice_Age_Temperature.png https://upload.wikimedia.org/wikipedia/commons/f/f8/Ice_Age_...

olliej 8y ago
All of those changes took place over extended periods of time, as opposed to the human generated climate change that is labeled “global warming”. The importance of timescales is very simple: evolution requires many generations to adapt, and the larger the change the more generations are needed. Literally no one argues that there have been no changes in global temperature. That is a straw man. The problem with human created global warming is that it is much much faster than any prior cycle, and that the mechanisms that are causing it (increased CO and CO2) have compounding ramifications - like ocean acidification - that are causing direct damage to major ecosystems, including the organisms that do absorb CO2. I don’t recall any studies of prior occurrences of this - I would expect that the impact would be gaps in things like the cliffs of Devon, etc where you’d see large scale (global) die offs of more or less all mollusks.
- TangoTrotFox 8y ago
  I assure you I'm not trying to strawman you. These conversations somehow always get so emotional so quickly, so I'm trying to be as forthright as possible. What I am reading from this post is that you're suggesting that since previous changes in temperature took place over extended periods of time, nature had time to evolve thus helping to minimize effects. That seems like a reasonable hypothesis. How long of a time do you think would be the minimum to allow for the presumably substantial evolutionary changes that would be required for adaptation? How does this contrast against the warming, potentially upwards of 10 degrees celsius, that occurred some 330k years ago - to say nothing of the sharp increases in CO2 that also followed? In particular, how rapidly do you suppose that warming occurred? [1] - https://upload.wikimedia.org/wikipedia/commons/f/f8/Ice_Age_Temperature.png https://upload.wikimedia.org/wikipedia/commons/f/f8/Ice_Age_...

olliej 8y ago

All of those changes took place over extended periods of time, as opposed to the human generated climate change that is labeled “global warming”. The importance of timescales is very simple: evolution requires many generations to adapt, and the larger the change the more generations are needed. Literally no one argues that there have been no changes in global temperature. That is a straw man. The problem with human created global warming is that it is much much faster than any prior cycle, and that the mechanisms that are causing it (increased CO and CO2) have compounding ramifications - like ocean acidification - that are causing direct damage to major ecosystems, including the organisms that do absorb CO2. I don’t recall any studies of prior occurrences of this - I would expect that the impact would be gaps in things like the cliffs of Devon, etc where you’d see large scale (global) die offs of more or less all mollusks.

TangoTrotFox 8y ago
I assure you I'm not trying to strawman you. These conversations somehow always get so emotional so quickly, so I'm trying to be as forthright as possible. What I am reading from this post is that you're suggesting that since previous changes in temperature took place over extended periods of time, nature had time to evolve thus helping to minimize effects. That seems like a reasonable hypothesis. How long of a time do you think would be the minimum to allow for the presumably substantial evolutionary changes that would be required for adaptation? How does this contrast against the warming, potentially upwards of 10 degrees celsius, that occurred some 330k years ago - to say nothing of the sharp increases in CO2 that also followed? In particular, how rapidly do you suppose that warming occurred? [1] - https://upload.wikimedia.org/wikipedia/commons/f/f8/Ice_Age_Temperature.png https://upload.wikimedia.org/wikipedia/commons/f/f8/Ice_Age_...