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Keep in mind if look at Venus from space (i.e. point an infrared-spectrum analyzer at it) it looks signficantly colder than Earth does from space, because even

Keep in mind if look at Venus from space (i.e. point an infrared-spectrum analyzer at it) it looks signficantly colder than Earth does from space, because even though the surface of Venus is very hot, it radiates to space at longer wavelengths because of the thickness of the atmosphere. If you increase atmospheric CO2 on Earth, you'd see a similar effect. Notice also that this debunks the 'Earth warming is due to increased solar output' claim, because if that was true, increased solar radiation inputs would result in a warming of the stratosphere, not a cooling. Imagine looking at a human in an IR scope at night. Then the human wraps themselves in a nice sleeping bag, and their apparent temperature decreases from the point of view of a remote observer. Even after equilibrium is reached, they'll still appear cooler due to thermal diffusion effects.

namaria 3y ago
>Notice also that this debunks the 'Earth warming is due to increased solar output' claim, because if that was true, increased solar radiation inputs would result in a warming of the stratosphere, not a cooling. While there's strong evidence that the increase in CO2 caused by human activity is causing global warming, the sun has increased output considerably over the eons, and Earth's surface was much hotter billions of years ago. Thin stratospheric air doesn't absorb nearly as much heat as denser layers closer to the ground and the ground and water themselves. Water is black in IR imaging because it absorbs so much of it!
- photochemsyn 3y ago
  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.
- cashsterling 3y ago
  Not to be too picky... but water is not black in IR imaging because it absorbs so much IR radiation. It is true that liquid water reflects very little IR radiation (less than 10%)... but water also emits thermal radiation (important to note that IR emission from water is quite different from black-body sources). Water that looks black in an image is simply emitting less IR radiation than other objects in the image... typically because the water is colder. See: https://www.youtube.com/watch?v=xcyU8oXBn6k https://www.youtube.com/watch?v=xcyU8oXBn6k <-- used to work on infrared detector development and IR radiometry
  - namaria 3y ago
    I was referring to IR satellite imagery where water bodies appear black.
    - cashsterling 3y ago
      same logic applies to all IR imagery including sat
friend_and_foe 3y ago
> Notice also that this debunks the 'Earth warming is due to increased solar output' claim, because if that was true, increased solar radiation inputs would result in a warming of the stratosphere, not a cooling. This is not necessarily true, if increased radiation hitting the water raised the temperature and caused release of dissolved carbon dioxide you'd see the stratospheric cooling effect no matter where that carbon dioxide came from. To be clear I'm not saying that global warming due to man made co2 isn't real. I think it is. But there is a scenario or hypothesis in which you might see stratospheric cooling as a result of increasing solar radiance. I don't know the exact numbers and I'm sure the math has been done on that showing that any co2 from oceans due to surface warming wouldn't have as pronounced an effect as we see and might get negated by absorption at higher altitudes, but the hypothesis is sound and I'm sure looking at data on it would be enlightening.

namaria 3y ago

>Notice also that this debunks the 'Earth warming is due to increased solar output' claim, because if that was true, increased solar radiation inputs would result in a warming of the stratosphere, not a cooling. While there's strong evidence that the increase in CO2 caused by human activity is causing global warming, the sun has increased output considerably over the eons, and Earth's surface was much hotter billions of years ago. Thin stratospheric air doesn't absorb nearly as much heat as denser layers closer to the ground and the ground and water themselves. Water is black in IR imaging because it absorbs so much of it!

photochemsyn 3y ago
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.
cashsterling 3y ago
Not to be too picky... but water is not black in IR imaging because it absorbs so much IR radiation. It is true that liquid water reflects very little IR radiation (less than 10%)... but water also emits thermal radiation (important to note that IR emission from water is quite different from black-body sources). Water that looks black in an image is simply emitting less IR radiation than other objects in the image... typically because the water is colder. See: https://www.youtube.com/watch?v=xcyU8oXBn6k https://www.youtube.com/watch?v=xcyU8oXBn6k <-- used to work on infrared detector development and IR radiometry
- namaria 3y ago
  I was referring to IR satellite imagery where water bodies appear black.
  - cashsterling 3y ago
    same logic applies to all IR imagery including sat

friend_and_foe 3y ago

> Notice also that this debunks the 'Earth warming is due to increased solar output' claim, because if that was true, increased solar radiation inputs would result in a warming of the stratosphere, not a cooling. This is not necessarily true, if increased radiation hitting the water raised the temperature and caused release of dissolved carbon dioxide you'd see the stratospheric cooling effect no matter where that carbon dioxide came from. To be clear I'm not saying that global warming due to man made co2 isn't real. I think it is. But there is a scenario or hypothesis in which you might see stratospheric cooling as a result of increasing solar radiance. I don't know the exact numbers and I'm sure the math has been done on that showing that any co2 from oceans due to surface warming wouldn't have as pronounced an effect as we see and might get negated by absorption at higher altitudes, but the hypothesis is sound and I'm sure looking at data on it would be enlightening.