Darmstadt 2008 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

UP: Fachverband Umweltphysik

UP 1: Atmosphäre und Klima

UP 1.11: Talk

Tuesday, March 11, 2008, 11:30–11:45, 3B

Optimized regularization for retrieval of partial column profiles from ground-based solar FTIR spectrometry — •Tobias Borsdorff and Ralf Sussmann — Research Center Karlsruhe, IMK-IFU, Kreuzeckbahnstr. 19, 82467 Garmisch-Partenkirchen,Germany

The retrieval of vertical profiles from ground based solar infrared spectra is an ill posed problem and regularization is the major tool to stabilize the solution. Whenever a suitable climatology is missing the optimal estimation approach is not applicable and soft constrains like the Tikhonov regularization are used. An example CO profile retrieval of solar infrared FT spectra is used to show that a sub-optimal regularization can already lead to a significant loss of vertical information. The relation between the chosen retrieval grid, the regularization matrix and the unit of the state vector is discussed in detail. The altitude resolved smoothing error and the vertical resolution due to different Tikhonov regularizations is examined. Finally it is discussed what kind of vertical information can be extracted from the derived retrieval results.