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Updated: Jun 15, 2026
06:27
Measurement of Aerosols Optical Thickness of the Atmosphere using the GLOBE Handheld Sun Photometer
Published on: May 29, 2019
Total ozone determination by spectroradiometry in the middle ultraviolet
Applied Optics
|March 9, 2010
Summary
A new method accurately determines total ozone using multispectral solar irradiance measurements. This technique accounts for aerosol extinction and has been validated with ground-based and balloon data, showing excellent agreement.
Area of Science:
- Atmospheric Science
- Spectroscopy
- Environmental Monitoring
Background:
- Accurate measurement of total ozone is crucial for understanding atmospheric processes and UV radiation.
- Previous methods faced challenges in accounting for atmospheric aerosols and precise wavelength calibration.
Purpose of the Study:
- To develop and validate a novel method for determining total ozone from direct solar irradiance.
- To assess the impact of aerosol extinction and wavelength calibration on ozone measurement accuracy.
Main Methods:
- Utilized multispectral measurements of direct solar irradiance between 290 nm and 380 nm.
- Employed a least squares fit for spectral analysis, incorporating a power series expansion for aerosol extinction.
- Developed a mobile laboratory with a sky scanner, automated by a minicomputer for data acquisition.
Main Results:
- The developed method demonstrated accurate total ozone determination.
- Results showed good agreement with simultaneous measurements from Dobson and Canterbury spectrometers, and ECC ozonesondes.
- Identified wavelength calibration and normalized ozone absorption values as critical factors for accuracy.
Conclusions:
- The novel multispectral method provides a reliable approach for total ozone determination.
- The mobile laboratory and data processing techniques proved effective for field validation.
- Precise calibration is essential for high-accuracy atmospheric ozone monitoring.
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