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On 9/18/2024 2:49 PM, D wrote:I take it you mean saturation in the IR spectrum. If you have some other intent with "chemical" saturation, please enlighten us.>Chemical saturation limits EVERYTHING but is rarely taken into account.
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On Wed, 18 Sep 2024, Scott Lurndal wrote:
>Lynn McGuire <lynnmcguire5@gmail.com> writes:>On 9/17/2024 6:11 PM, quadibloc wrote:>On Mon, 16 Sep 2024 16:29:18 +0000, Don wrote:
>>Global warming is not an imaginary spectre. The science involved is
really basic stuff.>>
Any Global Warming is not caused by humans so your basic thesis is
wrong.
You claim to be a process chemist, yet you make such
speciously _wrong_ statements. Svante August Arrhenius proved the
effects of CO2 on the atmosphere over a century ago (and earned
a Nobel prize in Chemistry).
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Why was Svante Arrhenius wrong about CO2?
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Introduction to Arrhenius’ Work Svante Arrhenius, a Swedish physical chemist, is often credited with the early scientific foundation of the greenhouse effect and global warming due to carbon dioxide (CO2). In his 1896 publication, he posited that a doubling of atmospheric CO2 could lead to an increase in global temperatures by approximately 5 to 6 degrees Celsius. This assertion was based on his calculations regarding the heat absorption properties of CO2 compared to water vapor.
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Overestimation of Temperature Increase One of the primary reasons Arrhenius was considered wrong about CO2’s impact on temperature is that he significantly overestimated the effect of a doubling of CO2 concentration. His initial calculations suggested a temperature rise between 5 and 6°C; however, later revisions indicated that this figure was too high. By 1906, after further analysis and feedback from contemporaries like Knut Ångström, Arrhenius revised his estimate downwards to around 1.2°C directly and up to 2.1°C when accounting for feedback effects from water vapor.
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Errors in Absorption Coefficient Arrhenius’s original calculations were heavily reliant on his estimates for the absorption coefficient of CO2. The absorption coefficient is crucial because it determines how effectively a gas can absorb infrared radiation (heat). Ångström challenged Arrhenius’s values, suggesting they were inaccurate. This discrepancy highlighted that Arrhenius had not fully accounted for the complexities involved in how different gases interact with infrared radiation.
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Neglecting Water Vapor’s Dominance Another critical factor in Arrhenius’s miscalculations was his underestimation of water vapor’s role as a greenhouse gas. Water vapor constitutes a much larger portion of the atmosphere compared to CO2 and has a more significant impact on climate due to its higher concentration and ability to absorb heat across various wavelengths. While Arrhenius recognized CO2 as an important greenhouse gas, he did not adequately emphasize that its effects would be overshadowed by those of water vapor.
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Advancements in Climate Science The understanding of climate dynamics has evolved significantly since Arrhenius’s time. Modern climate models incorporate complex interactions among various greenhouse gases, including feedback loops involving clouds and aerosols, which were not part of Arrhenius’s simpler models. These advancements have led to more accurate predictions regarding temperature increases associated with rising levels of CO2.
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Conclusion: Legacy and Misunderstandings While Svante Arrhenius laid important groundwork for understanding the greenhouse effect, subsequent research revealed that his initial estimates were overly optimistic due to errors in calculation methods and assumptions about atmospheric chemistry. His work serves as both a historical milestone in climate science and an example of how scientific understanding can evolve over time through rigorous testing and validation.
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