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Yes, the sun was producing more output 3 billion years ago. However I was discussing the Exxon-financed Willie Soon theory of sunspot modulation of Earth's cli

Yes, the sun was producing more output 3 billion years ago. However I was discussing the Exxon-financed Willie Soon theory of sunspot modulation of Earth's climate: https://www.theguardian.com/environment/2011/jun/28/climate-change-sceptic-willie-soon https://www.theguardian.com/environment/2011/jun/28/climate-... > "Dr Willie Soon, an astrophysicist at the Solar, Stellar and Planetary Sciences Division of the Harvard-Smithsonian Centre for Astrophysics, is known for his view that global warming and the melting of the arctic sea ice is caused by solar variation rather than human-caused CO2 emissions..." If he was correct then you wouldn't see a steady trend of stratospheric cooling, would you? However, if you were looking at an increase in the IR-absorbing blanket of atmospheric CO2, then you would expect it, right?

namaria 3y ago
I don't see how thin layers of air would heat before denser layers below. Less molecules equals less heat absorption.
- photochemsyn 3y ago
  Water vapor saturates infrared absorption low in the atmosphere, so adding CO2 at ground level has almost no effect on net IR absorption. It's only high in the atmosphere, where there is no water vapor, that added CO2 has a noticeable effect on net capture of infrared from Earth's surface that would otherwise escape to space. This was all verified in the 1950s, by the way. The fact that people still don't understand it can be put down to the disinformation put out by the fossi fuel lobby since the early 1980s, I suppose. https://history.aip.org/climate/Radmath.htm https://history.aip.org/climate/Radmath.htm > "Plass pursued a thorough set of one-dimensional computations, taking into account the structure of the absorption bands at all layers of the atmosphere. In 1956 he explained clearly, for the first time, that the water vapor absorption lines did not block the quite different CO2 absorption spectrum, adding that there was scarcely any water in the upper atmosphere anyway. He further explained that although some of the CO2 band itself was truly saturated, there were many lines to the side where adding more of the gas would increase the absorption of radiation. His arguments and calculations showed convincingly that adding or subtracting CO2 could seriously affect the radiation balance, layer by layer through the atmosphere, altering the temperature by a degree or more down to ground level."
  - namaria 3y ago
    >The fact that people still don't understand it can be put down to the disinformation put out by the fossi fuel lobby since the early 1980s, I suppose. Framing everything as truth vs disinformation is not a healthy way to foster debate. I am genuinely interested in understanding the mechanisms here. Don't call me a propaganda dupe because I don't fully grasp some concept or another.

namaria 3y ago

I don't see how thin layers of air would heat before denser layers below. Less molecules equals less heat absorption.

photochemsyn 3y ago
Water vapor saturates infrared absorption low in the atmosphere, so adding CO2 at ground level has almost no effect on net IR absorption. It's only high in the atmosphere, where there is no water vapor, that added CO2 has a noticeable effect on net capture of infrared from Earth's surface that would otherwise escape to space. This was all verified in the 1950s, by the way. The fact that people still don't understand it can be put down to the disinformation put out by the fossi fuel lobby since the early 1980s, I suppose. https://history.aip.org/climate/Radmath.htm https://history.aip.org/climate/Radmath.htm > "Plass pursued a thorough set of one-dimensional computations, taking into account the structure of the absorption bands at all layers of the atmosphere. In 1956 he explained clearly, for the first time, that the water vapor absorption lines did not block the quite different CO2 absorption spectrum, adding that there was scarcely any water in the upper atmosphere anyway. He further explained that although some of the CO2 band itself was truly saturated, there were many lines to the side where adding more of the gas would increase the absorption of radiation. His arguments and calculations showed convincingly that adding or subtracting CO2 could seriously affect the radiation balance, layer by layer through the atmosphere, altering the temperature by a degree or more down to ground level."
- namaria 3y ago
  >The fact that people still don't understand it can be put down to the disinformation put out by the fossi fuel lobby since the early 1980s, I suppose. Framing everything as truth vs disinformation is not a healthy way to foster debate. I am genuinely interested in understanding the mechanisms here. Don't call me a propaganda dupe because I don't fully grasp some concept or another.