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Metr 200/201 Thursday 2/22/01. Some more on OLR and ISR. The Stefan-Boltzmann Equation. Relates outward energy flux to temperature of a “black body”
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Metr 200/201 Thursday 2/22/01 Some more on OLR and ISR
The Stefan-Boltzmann Equation • Relates outward energy flux to temperature of a “black body” • You used this relation to calculate the monthly average emitting surface temperatures from the Climate Diagnostics Bulletin. The latest Climate Diagnostics Bulletins are available online here • Key assumption: “emitting surface” acts like a “black body"
Black Bodies • Are perfect absorbers and emitters of electromagnetic radiation • For practical purposes you can consider thick clouds and earth’s surface (land and water) as black body emitters of radiation • Thin clouds - and the clear atmosphere are most definitely not black bodies - they are selective absorbers of radiation
Selective absorbers /emitters • Gases (and thin clouds) are only able to absorb and emit radiation within certain wavelength ranges. For other wavelengths, gases do not absorb or emit any radiation - in other words, they are transparent to radiation in those wavelengths. • Black bodies, on the other hand absorb radiation over all wavelengths. In other words - black bodies are opaque.
How does the January 2001 OLR map compare with the one you analyzed? - How do the anomalies compare?