Synergistic multi-wavelength remote sensing versus a posteriori combination of retrieved products: Application for the retrieval of atmospheric profiles using MetOp-A
| Autor: | C. Prigent, O. Aznay, Frédéric Bernardo, M. Paul, Filipe Aires |
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| Rok vydání: | 2012 |
| Předmět: |
Atmospheric Science
010504 meteorology & atmospheric sciences Computer science 0207 environmental engineering Soil Science Multi wavelength 02 engineering and technology Aquatic Science Oceanography 01 natural sciences Fuzzy logic Geochemistry and Petrology Earth and Planetary Sciences (miscellaneous) 020701 environmental engineering 0105 earth and related environmental sciences Earth-Surface Processes Water Science and Technology Remote sensing Ecology Artificial neural network Paleontology Forestry Inversion (meteorology) Atmospheric temperature Geophysics Space and Planetary Science A priori and a posteriori Water vapor Microwave |
| Zdroj: | Journal of Geophysical Research: Atmospheres. 117 |
| ISSN: | 0148-0227 |
| Popis: | In this paper, synergy refers to a process where the use of multiple satellite observations makes the retrieval more precise than the best individual retrieval. Two general strategies can be used in order to use multi-wavelength observations in an inversion scheme. First, the multi-wavelength observations are merged in the input of the retrieval scheme. This means that the various satellite observations are used simultaneously and that their possible interactions can be exploited by the retrieval scheme. Second, each multi-wavelength observations are used independently to retrieve a same geophysical variable and then, these independent retrievals are combined a posteriori using for example a simple weighted averaging. In this paper, it is shown that the first approach provides better synergy results: The retrieval is better suited to optimize the use of all the information available because they are provided to the algorithm simultaneously. In particular, the retrieval process is able, in this case, to exploit the possible interactions between the various input information. The two retrieval approaches are tested and compared using an application for the retrieval of atmospheric profiles and integrated column quantities (temperature, water vapor, and ozone) using MetOp-A observations from IASI, AMSU-A and MHS instruments. Although real satellite observations are considered in this analysis, the results are dependent on the correlation structure in the training data set (i.e. ECMWF analysis) used to calibrate the retrieval algorithm. However, it can be seen that the infrared and microwave observations have a good synergy for the retrieval of atmospheric temperature, water vapor, and for ozone thanks to an indirect synergy. © American Geophysical Union. © 2012. American Geophysical Union. All Rights Reserved. |
| Databáze: | OpenAIRE |
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