Climate change in a shoebox: Right result, wrong physics
| Autor: | Chunhua Liu, Paul Wagoner, Roger G. Tobin |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Convection
Physics chemistry.chemical_classification Global warming General Physics and Astronomy Mechanics Atmospheric sciences chemistry Convective mixing Heat transfer Radiative transfer Compounds of carbon Absorption (electromagnetic radiation) Greenhouse effect Physics::Atmospheric and Oceanic Physics |
| Zdroj: | American Journal of Physics. 78:536-540 |
| ISSN: | 1943-2909 0002-9505 |
| DOI: | 10.1119/1.3322738 |
| Popis: | Classroom experiments that purport to demonstrate the role of carbon dioxide’s far-infrared absorption in global climate change are more subtle than is commonly appreciated. We show, using both experimental results and theoretical analysis, that one such experiment demonstrates an entirely different phenomenon: The greater density of carbon dioxide compared to air reduces heat transfer by suppressing convective mixing with the ambient air. Other related experiments are subject to similar concerns. Argon, which has a density close to that of carbon dioxide but no infrared absorption, provides a valuable experimental control for separating radiative from convective effects. A simple analytical model for estimating the magnitude of the radiative greenhouse effect is presented, and the effect is shown to be very small for most tabletop experiments. |
| Databáze: | OpenAIRE |
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