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1) Your meme-image does not show there is no relation. In fact, the source of one of the lines in the image is by Berner [1] which states (p. 201): "This means

1) Your meme-image does not show there is no relation. In fact, the source of one of the lines in the image is by Berner [1] which states (p. 201): "This means that over the long term there is indeed a correlation between CO2 and paleotemperature, as manifested by the atmospheric greenhouse effect." The source of your image directly contradicts your claim. 2) RE "unlikely that [...] there would be only one control knob": I never said there was only one. I said it was a control knob. And it is in fact the most important one (but not the only one) [2]. 3) RE "I've seen all of potholer54's videos.": I think you need to watch them again. [1] "Geocarb III: A Revised Model of Atmospheric CO2 over Phanerozoic Time ", http://www.ajsonline.org/content/301/2/182 http://www.ajsonline.org/content/301/2/182 [2] "Atmospheric CO2: Principal Control Knob Governing Earth’s Temperature", https://science.sciencemag.org/content/330/6002/356 https://science.sciencemag.org/content/330/6002/356 [3] As a side note: your image has no x- and y-axis scales. If you want to spread misleading images, at least use a better version (for instance, https://abruptearthchanges.files.wordpress.com/2019/07/no-long-term-correlation-between-co2-and-temperature.jpg?w=829 https://abruptearthchanges.files.wordpress.com/2019/07/no-lo...)

raarts 7y ago
The only thing you can say about the correlation in Geocarb II (my graph) and Geocarb III (your graph) is that 500 million years ago CO2 was 6000ppm and temperature 25ºC. Today CO2 is 410ppm, and temp 16ºC. That's it. So you could say there's a long term trend. But both graphs show wildly diverging lines between those points, in fact it was only during a few percent of the total time that the temperature rose when CO2 levels rose. This does not look like CO2 is mainly controlling the climate at all. So there is my problem. There are more problems, like the multiple periods of warming and cooling in the last 1000 years, that were just as bad or worse as what we're in now, but without human CO2. Like the fact that in the past CO2 followed temperature instead of preceding it (and the Milankovitch 'explanation' is not convincing at all), and like the fact that in recent years records are being shattered for cold weather all over the globe. And the media doesn't report about that. This thing about the climate is that everybody tells me to educate myself, and when I did, it only raised more questions.
- itcrowd 7y ago
  I am glad you're willing to educate yourself. I hope to give you at least a starting point and will try to address the points you made. 1) Regarding the correlations: The reason why you don't "see" the correlation (i.e. the lines don't perfectly overlap) if you plot CO2 and average global temperature is because there are other effects that obscure the correlation. For example, on the scales of 500 million years, the power coming from the sun (solar luminosity) has increased [1]. Milankovitch cycles are also important over longer timescales. Albedo changes of Earth's surface, etc. I have already cited the principle control knob paper. If you don't agree with the results, we can discuss that but, if so, please give some arguments instead of "I don't believe it". 2) "CO2 lags temperature": this is true in some cases. Vostok ice core is often cited and indeed the authors point to a ~1000 year difference between CO2 and temperature [2]. A more recent analysis [3] goes into more detail on a global sample. They find that on average, CO2 leads temperature but in the southern hemisphere, temperature leads CO2. This lag can be explained by ocean circulation changes. 3) "multiple periods of warming and cooling in the last 1000 years, that were just as bad or worse as what we're in now": A landmark paper was released this year reconstructing the global temperatures in the last 2000 years [4] and they concluded the current warming is global and warmer than ever. Other warm periods in the last 2000 years were simply a) not as warm AND/OR b) not global. One image says it all [5]. 4) Record cold not reported? I get a lot of search results from mainstream outlets when searching [6]. Of course, one cold/warm year does not disprove/prove global warming, but you know that. Also, weather and climate are different but you also know that. Popsci did an article explaining how this cold can be interpreted [7]. [1] For a short explanation, see Wikipedia: https://en.wikipedia.org/wiki/Solar_luminosity https://en.wikipedia.org/wiki/Solar_luminosity [2] "CO2‐climate relationship as deduced from the Vostok ice core: a re‐examination based on new measurements and on a re‐evaluation of the air dating", https://onlinelibrary.wiley.com/doi/abs/10.1034/j.1600-0889.1991.t01-1-00002.x https://onlinelibrary.wiley.com/doi/abs/10.1034/j.1600-0889.... [3] "Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation", https://www.nature.com/articles/nature10915 https://www.nature.com/articles/nature10915 [4] "No evidence for globally coherent warm and cold periods over the preindustrial Common Era", https://www.nature.com/articles/s41586-019-1401-2" https://www.nature.com/articles/s41586-019-1401-2" [5] Image from [4] https://media.springernature.com/full/springer-static/image/art%3A10.1038%2Fs41586-019-1401-2/MediaObjects/41586_2019_1401_Fig3_HTML.png?as=webp https://media.springernature.com/full/springer-static/image/... [6] https://duckduckgo.com/?q=record+cold+2019 https://duckduckgo.com/?q=record+cold+2019 [7] https://www.popsci.com/cold-weather-climate-change/ https://www.popsci.com/cold-weather-climate-change/

raarts 7y ago

The only thing you can say about the correlation in Geocarb II (my graph) and Geocarb III (your graph) is that 500 million years ago CO2 was 6000ppm and temperature 25ºC. Today CO2 is 410ppm, and temp 16ºC. That's it. So you could say there's a long term trend. But both graphs show wildly diverging lines between those points, in fact it was only during a few percent of the total time that the temperature rose when CO2 levels rose. This does not look like CO2 is mainly controlling the climate at all. So there is my problem. There are more problems, like the multiple periods of warming and cooling in the last 1000 years, that were just as bad or worse as what we're in now, but without human CO2. Like the fact that in the past CO2 followed temperature instead of preceding it (and the Milankovitch 'explanation' is not convincing at all), and like the fact that in recent years records are being shattered for cold weather all over the globe. And the media doesn't report about that. This thing about the climate is that everybody tells me to educate myself, and when I did, it only raised more questions.

itcrowd 7y ago
I am glad you're willing to educate yourself. I hope to give you at least a starting point and will try to address the points you made. 1) Regarding the correlations: The reason why you don't "see" the correlation (i.e. the lines don't perfectly overlap) if you plot CO2 and average global temperature is because there are other effects that obscure the correlation. For example, on the scales of 500 million years, the power coming from the sun (solar luminosity) has increased [1]. Milankovitch cycles are also important over longer timescales. Albedo changes of Earth's surface, etc. I have already cited the principle control knob paper. If you don't agree with the results, we can discuss that but, if so, please give some arguments instead of "I don't believe it". 2) "CO2 lags temperature": this is true in some cases. Vostok ice core is often cited and indeed the authors point to a ~1000 year difference between CO2 and temperature [2]. A more recent analysis [3] goes into more detail on a global sample. They find that on average, CO2 leads temperature but in the southern hemisphere, temperature leads CO2. This lag can be explained by ocean circulation changes. 3) "multiple periods of warming and cooling in the last 1000 years, that were just as bad or worse as what we're in now": A landmark paper was released this year reconstructing the global temperatures in the last 2000 years [4] and they concluded the current warming is global and warmer than ever. Other warm periods in the last 2000 years were simply a) not as warm AND/OR b) not global. One image says it all [5]. 4) Record cold not reported? I get a lot of search results from mainstream outlets when searching [6]. Of course, one cold/warm year does not disprove/prove global warming, but you know that. Also, weather and climate are different but you also know that. Popsci did an article explaining how this cold can be interpreted [7]. [1] For a short explanation, see Wikipedia: https://en.wikipedia.org/wiki/Solar_luminosity https://en.wikipedia.org/wiki/Solar_luminosity [2] "CO2‐climate relationship as deduced from the Vostok ice core: a re‐examination based on new measurements and on a re‐evaluation of the air dating", https://onlinelibrary.wiley.com/doi/abs/10.1034/j.1600-0889.1991.t01-1-00002.x https://onlinelibrary.wiley.com/doi/abs/10.1034/j.1600-0889.... [3] "Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation", https://www.nature.com/articles/nature10915 https://www.nature.com/articles/nature10915 [4] "No evidence for globally coherent warm and cold periods over the preindustrial Common Era", https://www.nature.com/articles/s41586-019-1401-2" https://www.nature.com/articles/s41586-019-1401-2" [5] Image from [4] https://media.springernature.com/full/springer-static/image/art%3A10.1038%2Fs41586-019-1401-2/MediaObjects/41586_2019_1401_Fig3_HTML.png?as=webp https://media.springernature.com/full/springer-static/image/... [6] https://duckduckgo.com/?q=record+cold+2019 https://duckduckgo.com/?q=record+cold+2019 [7] https://www.popsci.com/cold-weather-climate-change/ https://www.popsci.com/cold-weather-climate-change/