Optimal Estimation Retrieval of Aerosol Microphysical Properties in the Lower Stratosphere from
Stratospheric Aerosol and Gas Experiment (SAGE II) Satellite Data
PhD Student: Daniela Wurl
The main objective of this research is to develop a new algorithm which successfully retrieves aerosol microphysical properties from multispectral measurements of aerosol extinction. The ultimate aim is to contribute to an improvement of the current knowledge and accuracy of the global distribution of aerosol microphysical properties in the stratosphere. The new retrieval model takes a novel approach to the aerosol retrieval problem. This approach is based on Optimal Estimation retrieval theory and directly produces aerosol size distribution parameters along with an estimate of the associated retrieval uncertainty. From these, integrated quantities like surface area density and volume density can be derived. The success of the new model will be judged based on the following criteria: Firstly, the retrieved solutions have to be reasonably accurate, that means close to the true solutions; secondly, the associated retrieval uncertainties have to be a good estimate of the true error. Finally, a comparison of the new retrieval results with aerosol properties obtained from a different retrieval method, and with in situ measurements of aerosol properties, will give indications that the new method helps indeed to improve previous retrieval results.
A PDF version of a poster describing some initials results of the retrieval which was presented at the 2003 Conference of The Meteorological Society of New Zeland can be found here.