ASTRA Astrophysics and Space Sciences Transactions ASTRA 1810-6536 Copernicus GmbH Göttingen, Germany 10.5194/astra-7-315-2011 Forbush decreases – clouds relation in the neutron monitor era Dragić A. 1 Aničin I. 1 Banjanac R. 1 Udovičić V. 1 Joković D. 1 Maletić D. 1 Puzović J. 2 Institute of Physics, University of Belgrade, Pregrevica 118, Belgrade, Serbia Faculty of Physics, University of Belgrade, Studentski trg 16, Belgrade, Serbia 31 08 2011 7 3 315 318 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.astrophys-space-sci-trans.net/7/315/2011/astra-7-315-2011.html The full text article is available as a PDF file from http://www.astrophys-space-sci-trans.net/7/315/2011/astra-7-315-2011.pdf

The proposed influence of cosmic rays on cloud formation is tested for the effect of sudden intensity changes of CR (Forbush decreases) on cloudiness. An attempt is made to widen the investigated period covered by satellite observation of cloudiness. As an indicator of cloud cover, the diurnal temperature range (DTR - a quantity anticorrelated with cloudiness) is used. The superposed epoch analysis on a set of isolated Forbush decreases is conducted and the results for a region of Europe are presented. The effect of Forbush decrease on DTR is statistically significant only if the analysis is restricted to high amplitude FDs (above the threshold value of 7% with the respect to undisturbed CR intensity). The magnitude of the effect on DTR is estimated to be (0.38 ± 0.06) °C.

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