ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-7-1435-2007 Technical Note: Regularization performances with the error consistency method in the case of retrieved atmospheric profiles Ceccherini S. 1 Belotti C. 1 Carli B. 1 Raspollini P. 1 Ridolfi M. 2 Istituto di Fisica Applicata "Nello Carrara" del Consiglio Nazionale delle Ricerche, Via Madonna del Piano, 10 – 50019 Sesto Fiorentino, Italy Dipartimento di Chimica Fisica e Inorganica, Università di Bologna, Viale del Risorgimento, 4 – 40136 Bologna, Italy 12 03 2007 7 5 1435 1440 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/7/1435/2007/acp-7-1435-2007.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/1435/2007/acp-7-1435-2007.pdf

The retrieval of concentration vertical profiles of atmospheric constituents from spectroscopic measurements is often an ill-conditioned problem and regularization methods are frequently used to improve its stability. Recently a new method, that provides a good compromise between precision and vertical resolution, was proposed to determine analytically the value of the regularization parameter. This method is applied for the first time to real measurements with its implementation in the operational retrieval code of the satellite limb-emission measurements of the MIPAS instrument and its performances are quantitatively analyzed. The adopted regularization improves the stability of the retrieval providing smooth profiles without major degradation of the vertical resolution. In the analyzed measurements the retrieval procedure provides a vertical resolution that, in the troposphere and low stratosphere, is smaller than the vertical field of view of the instrument.

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