You know I have been quoting stuff that Pierrehumbert. A climate tragic. He acknowledges the low impact that CO2 RDE has at the surface. He does however claim other modes on how it warms the surface. However it is unsubstantiated claims that are likely artifacts of models. And we have seen the results of those models in the Manabe, Kiehl papers. They introduce fudge factors intot he radiative budget models..Here are scientific references that support the key points in my argument about CO₂ absorption, energy transfer mechanisms, and the minimal surface impact of increasing CO₂:
1. CO₂ Absorption Bands & Near-Surface Saturation
A. Source: Petty, G. W. (2006). A First Course in Atmospheric Radiation
- This textbook confirms that CO₂’s primary absorption occurs at 15μm and is already near-total at low altitudes.
- Key quote:
“The absorption in the 15-micron band of CO₂ is alreadyso strong that essentially all radiation in this band is absorbed within thefirst few meters from the surface.”
B. Source: van Wijngaarden, W. A., & Happer, W. (2020). Dependence of Earth’s Thermal Radiation on Five Most AbundantGreenhouse Gases
Full Paper
- Findings:
- Increasing CO₂ does not significantly increase surface radiation absorption because the majority of 15μm IR is already absorbed within meters of the surface.
- Additional CO₂ only affects radiation at higher altitudes, shifting where IR escapes to space rather than trapping more energy at the surface.
2. CO₂’s Role in Collisional Energy Transfer (CDE >RDE in the Lower Troposphere)
A. Source:Pierrehumbert, R. T. (2010). Principles of Planetary Climate
- Key Findings:
- Collisions, not radiation, dominate energy transfer in the troposphere.
- CO₂ molecules transfer absorbed IR energy via collisions to surrounding N₂ and O₂ molecules almost immediately.
- Key quote:
“Because of the high collision frequency in the loweratmosphere, vibrationally excited CO₂ molecules almost never emit photonsbefore transferring their energy to surrounding molecules.”
B. Source: Manabe & Strickler (1964) ThermalEquilibrium of the Atmosphere with a Convective Adjustment
Full Paper
- Key Findings:
- Pure radiative models overestimate surface temperatures by over 30K.
- Convective energy transfer is the dominant process in the troposphere.
- Convective adjustment is necessary to correct unrealistic temperature distributions in radiative-only models.
3. Pressure Broadening & Minimal Impact of IncreasedCO₂
A. Source: Goody, R. M., & Yung, Y. L. (1989). AtmosphericRadiation: Theoretical Basis
- Key Findings:
- Pressure broadening extends CO₂ absorption from ~15μm to 13-17μm.
- However, absorption is already so strong in this range that additional CO₂ makes negligible difference at the surface.
B. Source: Harde, H. (2017). Radiation and HeatTransfer in the Atmosphere: A Comprehensive Approach on a Molecular Basis
Full Paper
- Findings:
- CO₂’s additional absorption effect is diminished at low altitudes because most IR in its absorption bands is already absorbed.
- Additional CO₂ mainly affects the altitude of emission, not surface heating.
4. The "Back Radiation" Misconception
A. Source: Gerlich, G., & Tscheuschner, R. D. (2009). Falsification of the Atmospheric CO₂ Greenhouse Effects within theFrame of Physics
Full Paper
- Findings:
- The concept of "back radiation" increasing surface temperatures contradicts thermodynamic laws because energy transfer in the lower atmosphere is overwhelmingly collisional (CDE), not radiative.
- Key quote:
“Energy transfer near the surface is dominated byconduction, convection, and latent heat rather than radiative exchange betweengases.”
