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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
Stratospheric aerosol measurements with implications for global climate
Applied Optics
|February 4, 2010
Summary
Bistatic optical probing measured stratospheric aerosol layers between 12-25 km. This research provides a chronology of aerosol levels, crucial for understanding climate and volcanic dust impacts.
Area of Science:
- Atmospheric optics
- Stratospheric aerosol research
- Climate science
Background:
- Stratospheric aerosols influence global climate.
- Understanding aerosol layer structure is key to climate modeling.
- Previous studies lacked detailed vertical profiles.
Purpose of the Study:
- To present measurement results of atmospheric aerosol attenuation coefficients.
- To determine the structure and parameters of the stratospheric aerosol layer.
- To examine volcanic dust incursions and establish a chronology of aerosol levels.
Main Methods:
- Bistatic optical probing of the atmosphere using a searchlight beam.
- Obtained forty-one vertical profiles of aerosol attenuation coefficients (12-25 km).
- Developed a chronology of stratospheric aerosol concentration levels since 1963.
Main Results:
- Identified a double-layered mean stratospheric aerosol distribution with maxima at 15.6 km and 19.3 km.
- Examined an early phase of volcanic dust incursion.
- Established a background aerosol optical thickness (Tau(p)(0.55 micro)) of 2.0 x 10(-2) for a non-volcanic stratosphere.
Conclusions:
- Stratospheric aerosol profiles provide valuable information on aerosol layer structure.
- The study supports the feasibility of a laser-satellite method for global climate data acquisition.
- An original numerical integration method for radiative transfer studies was introduced.
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