Advances in Geosciences www.adv-geosci.net 1680-7340 1680-7359 20 Observation, Prediction and Verification of Precipitation (EGU Session 2008) 2009 10.5194/adgeo-20-45-2009 http://www.adv-geosci.net/20/45/2009/ http://www.adv-geosci.net/20/45/2009/adgeo-20-45-2009.html http://www.adv-geosci.net/20/45/2009/adgeo-20-45-2009.pdf 45 50 2009-04-07 Characteristics of the extreme warm and cold days over Greece M. S. Varfi varfi@geo.auth.gr T. S. Karacostas T. J. Makrogiannis A. A. Flocas Department of Meteorology and Climatology, Aristotle University of Thessaloniki, Greece An attempt is made to study the characteristics of the extreme warm and cold days over the major area of Greece. To meet this objective, the daily maximum and minimum air temperature values are used, obtained from seventeen (17) synoptic weather stations, covering the broad study area. The extreme warm and cold days are identified based upon the proposed and adopted criteria, which are applied for the period 1961–2000. Seven regional decadal indices measuring the frequency of occurrence, the magnitude and the intensity of the extreme temperature values are calculated. The study of the indices revealed that after the 70' the frequency of occurrence and the intensity of cold days follow a negative trend, as opposed to the frequency of occurrence and the intensity of the warm days that follow a positive trend. Moreover, the proposed indices confirm the cooling conditions that Greece experienced in the 70's and early 80's and the warming trend afterwards. Alexander, L. V., Zhang, X., Peterson, T. C., Caesar, J., Gleason, B., Tank, K., Haylock, M., Collins, D., Trewin, B., Rahimzadeh, F., Tagipour, A., Rupa Kumar, K., Revadekar, J., Griffiths, G., Vincent, L., Stephenson, D. B., Burn, J., Aguilar, E., Brunet, M., Taylor, M., New, M., Zhai, P., Rusticucci, M., and Vazquez-Aguirre, J. L.: Global observed changes in daily climate extremes of temperature and precipitation, J. Geophys. Res., 111, D05109, doi:10.1029/2005JD006290, 2006. Alexanderson, H.: A homogeneity test applied to precipitation data, J. Climatol., 6, 661–675, 1986. Burgueno, A., Lana, X., and Serra, C.: Significant hot and cold events at the Fabra Observatory, Barcelona (NE Spain), Theor. Appl. Climatol. 71, 141–156, 2002. Cartalis, C., Chrysoulakis, N., Feidas, H., and Pitsitakis, N.: Categorization of cold period weather types in Greece on the basis of the photointerpretation of NOAA/AVHRR imagery, Int. J. Remote Sens., 25, 2951–2977, 2004. Chan, K., Mysterud, A., Øritsland, N., Severinsen, T., and Stenseth, N.: Continuous and discrete extreme climatic events affecting thw dynamics of a high-arctic reindeer population, Oecologia, 145, 556–563, 2005. Chagnon, S. A.: Measures of economic impacts of weather extremes, B. Am. Meteorol. Soc., 84, 1231–1235, 2003. Della-Marta, P. M., Haylock, M. R., Luterbacher, J., and Wanner, H.: Doubled length of western European summer heat waves since 1880, J. Geophys. Res., 112, D151103, doi:10.1029/2007JD008510, 2007a. Feidas, H., Makrogiannis, T., and Bora-Senta, E.: Trend analysis of air temperature time series in Greece and their relationship with circulation using surface and satellite data: 1955–2001, Theor. Appl. Climatol., 79, 185–208, 2004. Frich, P., Alexander, L. V., Della-Marta, P., Gleason, B., Haylock, M., Klein Tank, A. M. G., and Peterson, T.: Observed coherent changes in climatic extremes during the second half of the twentieth century, Climate Res., 19, 193–212, 2002. Giles, B. D. and Flocas, A. A.: Air temperature variations in Greece, Part 1. Persistence, trend, and fluctuations, Int. J. Climatol., 4, 531–539, 1984. IPCC, Climate Change 1995: The science of Climate Change: Contribution of Working Group I to the second Assessment Report of the Intergovernmental Panel on Climate, Cambridge: Cambridge University Press, 1996. Kostopoulou, E. and Jones, P. D.: Assesment of climate extremes in the Eastern Mediterranean, Meteorol. Atmos. Phys., 89, 69–85, 2005. Luterbacher, J., Xoplaki, E., Burgard, R., and Schmutz, C.: Connection between the large scale lower atmospheric circulation and the winter temperature variability over Greece: 1957–1997. Proc. 5th Greek Scientific Conference in Meteorology-Climatology-Atmospheric Physics, Thessaloniki, 28–30~September 2000, 81–88, 2000. Maheras, P., Patrikas, I., Karacostas, T., and Anagnostopoulou, C.: Automatic classification of circulation types in Greece: methodology, description, frequency, variability and trend analysis, Theor. Appl. Climatol., 67, 205–223, 2000. Maheras, P., Flokas, H., Tolika, K., Anagnostopoulou, C., and Vafiadis, M.: Circulation types and extreme temperature changes in Greece, Climate Res., 30, 161–174, 2006. Mazarakis, N., Kotroni, V., Lagouvardos, K., and Argiriou, A.: Storms and lightning activity in Greece during the warm periods of 2003–2006, J. Appl. Meteorol. Clim., 47, 3089–3098, 2008. Moberg, A. and Jones, P. H.: Trends in indices for extremes in daily temperature and precipitation in central and western Europe, 1901–1999, Int. J. Climatol., 25, 1149–1171, 2005. Proedrou, M., Theoharatos, G., and Cartalis, C.: Variations and trends in annual and seasonal air temperature in Greece determined from ground and satellite measurements, Theor. Appl. Climatol., 57, 65–78, 1997. Rusticucci, M., and Vargas, W.: Cold and warm events over Argentina and their relationship with the ENSO phases: risk evaluation analysis, Int. J. Climatol., 22, 467–483, 2002. Tank, K. and Können, G. P.: Trends in indices of daily temperature and precipitation extremes in Europe, 1946–1999, J. Climate, 16, 3665–3680, 2003. Tank, K., Wungaard, J. B., Koennen, G. P. and co-authors: Daily dataset of 20th-century air temperature and precipitation series for the European climate assessment, Int. J. Climatol., 22, 1441–1456, 2002. Xoplaki, E., Luterbacher, J., and Gonzalez-Rouco, J. F.: Mediterranean summer temperature and winter precipitation, large-scale dynamics, trends, Il Nuovo Cimento, 29(1), doi:10.1393/ncc/i2005-10220-4, 2005.