An Investigation of Methods for Computing Long Path Atmospheric Transmittance

Abstract

The reliability of the statistical band model for long path length, low transmittance conditions is investigated by comparing the band model with precise line by line calculations. Two test systems are utilized; a system of H2O absorbers and a system of computer generated line parameters. It is found that the statistical band model is fairly reliable for calculating band transmittance in the range bar T > 0.1, but for transmittance less than this, it is not reliable and can be in error by several orders of magnitude. An explanation for this behavior is offered. In the second part of this investigation, an new nonstatistical method based on a simple approximation of the k-distribution function is developed. It is compared with precise line by line calculations and is found to be very reliable for all transmittance conditions.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1982
Accession Number
ADA134877

Entities

People

  • B R Johnson

Organizations

  • The Aerospace Corporation

Tags

Communities of Interest

  • Energy and Power Technologies
  • Space

DTIC Thesaurus Topics

  • Absorption Coefficients
  • Accuracy
  • Air Force
  • Analytic Functions
  • Classification
  • Coefficients
  • Computers
  • Data Analysis
  • Distribution Functions
  • Physics Laboratories
  • Probability
  • Random Variables
  • Reliability
  • Security
  • Spectra
  • Statistical Samples
  • Transmittance

Fields of Study

  • Physics

Readers

  • Regression Analysis.
  • Spectroscopy.