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Related Experiment Video

Updated: Jun 17, 2026

Non-equilibrium Microwave Plasma for Efficient High Temperature Chemistry

Non-equilibrium Microwave Plasma for Efficient High Temperature Chemistry

Published on: August 1, 2017

Radiation from nonisothermal gases.

¹The Southwest Center for Advanced Studies,P. 0. Box 30365, Dallas, Texas 75230, USA.

|January 12, 2010

Summary

This study presents general equations for calculating gas radiance using spectral line equivalent widths. The method is validated against exact calculations for various temperature profiles.

Area of Science:

Atmospheric Science
Radiative Transfer
Spectroscopy

Background:

Understanding atmospheric radiance is crucial for climate modeling and remote sensing.
Accurate calculations require considering gas properties and spectral line characteristics.

Purpose of the Study:

To derive general expressions for nonisothermal gas radiance.
To provide a flexible method adaptable to different equivalent width calculations.
To compare a new approximation with exact methods.

Main Methods:

Derivation of radiance expressions based on spectral line equivalent widths.
Utilizing both band model theory and exact calculations for equivalent widths.
Application of the Curtis-Godson approximation for radiance calculations.

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Comparison with exact radiance computations.

Main Results:

General formulas for gas radiance were successfully derived.
The Curtis-Godson approximation provides a viable method for radiance estimation.
Calculations demonstrated the method's applicability across diverse temperature distributions.

Conclusions:

The derived expressions offer a versatile approach to calculating atmospheric radiance.
The method integrates various spectral line width treatments.
This work facilitates more accurate radiative transfer modeling.