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06:27
Measurement of Aerosols Optical Thickness of the Atmosphere using the GLOBE Handheld Sun Photometer
Published on: May 29, 2019
Measured trends in stratospheric ozone
Science (New York, N.Y.)
|April 17, 1992
Summary
Northern Hemisphere ozone levels show a downward trend, particularly in the lower stratosphere. Multiple ground-based and satellite measurements confirm these findings, indicating significant stratospheric ozone depletion.
Area of Science:
- Atmospheric chemistry and physics
- Stratospheric science
- Ozone layer research
Background:
- Ozone depletion is a significant environmental concern.
- Understanding ozone trends is crucial for climate modeling.
- Previous studies indicated potential ozone layer changes.
Purpose of the Study:
- To analyze recent trends in total ozone column amounts.
- To investigate altitude-specific changes in ozone concentration.
- To confirm findings using multiple data sources.
Main Methods:
- Analysis of ground-based ozone records from 29 stations.
- Examination of satellite data from Total Ozone Mapping Spectrometer (TOMS) and Stratospheric Aerosol and Gas Experiment (SAGE).
- Comparison of data from multiple instruments for consistency.
Main Results:
- Confirmed a downward trend in total ozone column over Northern Hemisphere mid-latitudes across all seasons.
- Identified ozone concentration decreases in the lower stratosphere, the region of peak ozone.
- Data from various instruments provide a consistent picture of stratospheric ozone changes.
Conclusions:
- Stratospheric ozone levels have demonstrably decreased over Northern Hemisphere mid-latitudes.
- Multiple independent measurement techniques corroborate these findings.
- The observed ozone depletion has significant implications for atmospheric health.
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