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Near infrared atmospheric absorption over a 25-knm horizontal path at sea level
J L Streete1, J H Taylor, S L Ball
1Laboratory of Atmospheric and Optical Physics, Southwestern at Memphis, Memphis, Tennessee, USA.
Applied Optics
|January 9, 2010
Summary
Atmospheric absorption spectra were measured over a 25-km sea-level path using carbon arc searchlights. Results reveal spectral absorption patterns influenced by varying water vapor content.
Area of Science:
- Atmospheric optics
- Spectroscopy
Background:
- Atmospheric absorption spectra are crucial for understanding radiation transfer.
- Previous studies have focused on various atmospheric paths and conditions.
Purpose of the Study:
- To present atmospheric absorption spectra over a 25-km horizontal, sea-level path.
- To compare these spectra with solar spectra for atmospheric analysis.
Main Methods:
- Utilized six 150-cm diameter carbon arc searchlights as continuous radiation sources.
- Obtained spectra over a 0.68 to 4.86 micrometer range with varying resolution.
- Measured water vapor content from 9 to 39 precipitable cm.
Main Results:
- Presented detailed atmospheric absorption spectra from the Cape Kennedy area.
- Compared horizontal path spectra with concurrent sea-level solar spectra.
- Observed spectral absorption variations correlated with water vapor levels.
Conclusions:
- The study provides valuable spectral data for atmospheric transmission research.
- Demonstrated the impact of water vapor on atmospheric absorption spectra.
- Established a baseline for further atmospheric spectroscopy investigations.
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