ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-7-5543-2007 The effect of the total solar eclipse of 29 March 2006 on meteorological variables in Greece Founda D. 1 Melas D. 2 Lykoudis S. 1 Lisaridis I. 2 Gerasopoulos E. 1 Kouvarakis G. 3 Petrakis M. 1 Zerefos C. 1 National Observatory of Athens, Institute for Environmental Research and Sustainable Development, Greece Aristotle University of Thessaloniki, Physics Department, Laboratory of Atmospheric Physics, Thessaloniki, Greece University of Crete, Chemistry Department, Environmental and Chemical Processes Laboratory, Crete, Greece 06 11 2007 7 21 5543 5553 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/7/5543/2007/acp-7-5543-2007.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/5543/2007/acp-7-5543-2007.pdf

This paper examines the effect of the total solar eclipse of 29 March 2006 on meteorological variables across Greece. Integrated micrometeorological measurements were conducted at Kastelorizo, a small island within the path of totality, and other sites within the Greek domain, with various degrees of solar obscuration. The observations showed a dramatic reduction in the incoming global radiation and subsequent, pronounced changes in surface air temperature with the lowest temperature values occurring about 15 min after the full phase. The amplitude of the air temperature drop was not analogous to the obscuration percentage but was principally determined by the surrounding environment (mainly the sea influence), the background meteorological conditions and local cloudiness. Surface wind-speed decreased in most sites as a result of the cooling and stabilization of the atmospheric boundary layer. This perturbation provided a unique opportunity to apply a sensitivity analysis on the effect of the eclipse to the Weather Research and Forecast (WRF) numerical mesoscale meteorological model. Strong anomalies, not associated with a dynamic response, were simulated over land especially in surface air temperature. The simulated temperature drop pattern was consistent with the observations.

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