Category Archives: MODTRAN

The Temperature and Altitude of Radiation to Space III

We left of the last post having found that brightness temperature was hopelessly asymmetric to radiance in the main CO2 deviation from the Planck temperature. This discovery dashed all hope of using brightness temperature to determine the temperatures of the … Continue reading

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The Temperature and Altitude of Radiation to Space

This post was begun some time ago and we experienced so much trouble replicating the MODTRAN Planck curves that two rambling subsequent posts transpired recounting the misadventure. Here, and here. We eventually concluded that the Planck curves in the MODTRAN … Continue reading

Posted in Greenhouse Spectra, MODTRAN, Radiance | 1 Comment

Alalyzing the MODTRAN Planck Curves

This post reports on some progress on resolving our difficulty replicating MODTRAN Planck curves in a prior post. In a personal communication, Dr. David Archer kindly provided the spreadsheet used to produce the MODTRAN curves. The standard wave number Planck … Continue reading

Posted in MODTRAN, Radiance | 6 Comments

A Brief History of Muddled Thinking about the Greenhouse Effect

We humans kick up a lot of dust and burn a lot of stuff. A concept developed in the 1970’s was the “human volcano”. There is a lot of truth in this analogy. Back then, despite dead wrong rants, the … Continue reading

Posted in Climate, Greenhouse Effect, Greenhouse Spectra, MODTRAN | 6 Comments

MODTRAN, The One ppm Exercise

MODTRAN is impressively nuanced sometimes. Ordinarily MODTRAN is used on a macro scale at plausible altitudes and greenhouse gas concentrations, but it definitely resolves at single meters of altitude and single ppm of greenhouse gasses. Here we explore one ppm … Continue reading

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One often hears it said that the “heat absorbing” properties of CO2 in the atmosphere are “well known” or “well understood”. This is definitely not the case. The properties of CO2 in the atmosphere are presupposed  to be simple, and held up … Continue reading

Posted in Climate, MODTRAN | 6 Comments