CPD Climate of the Past Discussions CPD 1814-9359 Copernicus GmbH Göttingen, Germany 10.5194/cpd-6-461-2010 Statistical issues about solar-climate relations Yiou P. 1 Bard E. 5 Dandin P. 4 Legras B. 2 Naveau P. 1 Rust H. W. 1 Terray L. 3 Vrac M. 1 Laboratoire des Sciences du Climat et de l'Environnement, UMR CEA-CNRS-UVSQ 8212, IPSL, Gif-sur-Yvette, France Laboratoire de Météorologie Dynamique, UMR 8539, Ecole Normale Supérieure, Paris, France Centre Européen de Recherche et Formation Avancées en Calcul Scientifique, Toulouse, France Météo-France, Division de la Climatologie, Toulouse, France Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement, UMR 6635, Aix-en-Provence, France 07 04 2010 6 2 461 487 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.clim-past-discuss.net/6/461/2010/cpd-6-461-2010.html The full text article is available as a PDF file from http://www.clim-past-discuss.net/6/461/2010/cpd-6-461-2010.pdf

Assessing the relationship between temperature variations and solar activity requires much physical and statistical insight. This paper is devoted to the latter. We focus on the statistical significance of diagnostics to obtain properties of the variability of time series. We illustrate our study by analyses of European temperature datasets and geomagnetic field variations. The goal of the paper is to provide a framework to control the spurious results that statistical tools can generate. We show that some variability diagnostics barely distinguish observed temperatures from auto-regressive random processes. In general, the variability diagnostics between temperature and geomagnetic activity are not significantly correlated, due to a low number of degrees of freedom.

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