Remote sensing of urban aerosol from space
Zusammenfassung der Projektergebnisse
The scientific objective for the project were a) the assessment of the capability and limitations of the existing retrieval algorithms for aerosol data products using the different current sources of passive remote sensing data and, b) the development of the aerosol retrieval algorithm which account for the polarization of electromagnetic radiation, scattered by atmospheric aerosol. To achieve the above goals the current scientific capability of retrieval algorithms was investigated. In this context the performance of diverse satellite aerosol retrieval algorithms have been investigated for different types and sources of data measuring electromagnetic radiation back scattered from the atmosphere: spectral measurements, multi-angular spectral and polarimetric measurements. Radiative transfer simulations. were used extensively in these comparisons. A prerequisite for a retrieval utilizing polarization information is an adequate radiative transfer simulation. For this purpose the vector version of the radiative transfer code SCIATRAN, which was used for the preparation of look-up-tables (LUTs) was prepared and LUTs were calculated for use in the algorithm. The initial guess value of aerosol optical thickness is selected on the basis of the approximate solution of the radiative transfer problem. Finally a new retrieval algorithm (P-BAER) was then created using the knowledge gained from the previous studies about information content. P-BAER was tested using synthetic top-of- atmosphere data. As a first test the particulate matter concentrations over Germany was determined using the developed retrieval procedure. As originally foreseen, it is planned to apply the developed algorithm to satellite data over megacities to improve our understanding optical and microphysical properties of urban aerosol and their changes over the past 2-3 decades.
Projektbezogene Publikationen (Auswahl)
- 2009. Determination of particulate matter vertical columns using satellite observations. Atmos. Meas. Techniques, 2, 327-335
Kokhanovsky, A. A., et al.
- 2010. Benchmark results in vector atmospheric radiative transfer. JQSRT, 111, 1931-1946
Kokhanovsky, A. A., et al.
- 2010. The inter-comparison of major aerosol retrieval algorithms using simulated intensity and polarization characteristics of reflected light. Atmos. Meas. Techniques, 3, 909-932
Kokhanovsky, A. A., et al.
- 2011. Retrieval of spectral aerosol optical thickness over land using ocean colour sensors MERIS and SeaWiFS. Atmospheric Measurement Techniques, 4, 151- 171
W. von Hoyningen-Huene, J. Yoon, M. Vountas, L. G. Istomina, G. Rohen, T. Dinter, A. A. Kokhanovsky, and J. P. Burrows