Solar radiation and aerosols
Both gases and suspended particles (aerosols) affect atmospheric composition and are involved in a variety of chemical and physical reactions such as ozone depletion, smog formation and cloud formation. We make measurements to understand how our atmosphere is changing around us.
Sunlight (more formally Solar Radiation) is vital in shaping and changing our atmosphere. We quantify UV and visible solar radiation to determine how rapidly it will drive chemical reactions. This quantification allows the estimation of atmospheric photolysis rates, a key component in understanding the forces driving the chemistry of the atmosphere.
Gases in the atmosphere absorb solar radiation and can give very specific ‘solar radiation signatures’. These signatures can be measured and allow determination of atmospheric composition. We carry out long-term and campaign based measurements of both direct (Direct sun Differential Optical Absorption Spectrometry) and scattered sunlight (Multi-Axis Differential Optical Absorption Spectrometry) to quantify reactive components in the atmosphere such as formaldehyde, NO2 and BrO, as well as atmospheric aerosols.
The quantification of the radiation arriving directly from the sun allows the optical properties of aerosols to be measured. These measurements are made at Wollongong and Cape Grim in conjunction with the Bureau of Meteorology. We complement these optical aerosol measurements with measurements of the physical (size, number) and chemical composition of aerosols through collaboration with CSIRO Marine and Atmospheric Research.
Contacts: A/Prof Stephen Wilson
- Wilson, S. R., and B. W. Forgan (2002), Aerosol optical depth at Cape Grim, Tasmania 1986-1999, J. Geophys. Res., 107(D8), 4068, doi:10.1029/2001JD000398.