Advances in Science and Research www.adv-sci-res.net 1992-0628 1992-0636 2 7th EMS Annual Meeting and 8th European Conference on Applications of Meteorology 2007 2008 10.5194/asr-2-17-2008 http://www.adv-sci-res.net/2/17/2008/ http://www.adv-sci-res.net/2/17/2008/asr-2-17-2008.html http://www.adv-sci-res.net/2/17/2008/asr-2-17-2008.pdf 17 20 2008-04-07 Analysis of a low ozone episode over Extremadura (Spain) in January 2006 and its influence on UV radiation M. Antón mananton@unex.es M. L. Cancillo A. Serrano J. A. García F. J. Acero Departamento de Física, Universidad de Extremadura, Badajoz, Spain The main objectives of this work are to analyze, firstly, the detail of the causes of a low ozone event which occurred in January 2006 and, secondly, the related effects of this anomalous episode on ultraviolet (UV) radiation measured at three locations in Extremadura (South-Western Spain). On 19 January 2006, the OMI total ozone column (TOC) was 16–20% below the January mean value of TOMS/NASA TOC (period 1996–2005). The back trajectories analysis with the HYSplit model indicates that the notable decrease of TOC could be attributed to a fast rise of the isentropic trajectories height. Concomitantly, UV erythemal radiation greatly increases (between 23% and 37%) on 19 January 2006 respect to UV erythemal radiation measured on 19 January 2005. This notable increase in winter UV solar radiation may involve harmful effects for organisms adapted to receive less radiation during that season (e.g. early developmental stages of terrestrial plants and phytoplankton). Allart, M., Valks, P., Van der A, R., Piters, A., Kelder, H., and Van Velthoven, P.: Ozone mini-holes observed over Europe, influence of low stratospheric temperature on observations, Geophys. Res. Lett., 27, 4089–4092, 2000. Antón, M.: Modelos empíricos para la estimación de la irradiancia solar ultravioleta, Ph Thesis, University of Extremadura, 2007. Antón, M., Cancillo, M. L., Serrano, A., Vaquero, J. M., and García, J. A.: Ozone mini-hole over southwestern Spain during January 2004: Influence over ultraviolet radiation, Geophys. Res. Lett., 34, L10808, doi:10.1029/2007GL029689, 2007. Austin, J., Driscoll, C. M. H., Farmer, S. F. G., and Molyneux, M. J.: Late spring ultraviolet levels over the United Kingdom and the link to ozone, Ann. Geophys., 17, 1199–1209, 1999. Bojkov, R. D. and Balis, D. S.: Characteristics of episodes with extremely low ozone values in the northern middle latitudes 1957–2000, Ann. Geophys., 19, 797–807, 2001. Córdoba, C., Aguirre, I., Pérez, A., Sanz, A., Angulo, C., Vila, P., Monroy, E., Muñoz, E., and Jaque, F.: UV-B irradiance at Madrid during 1996, 1997 and 1998, J. Geophys. Res., 105, 4903–4906, 2000. Draxler, R. R. and Hess, G. D.: Description of the HySplit_4 Modelling System, NOAA Technical Memorandum, ERL ARL-224, December, 24 pp., 1997. Iwao, K.: Dynamical quantifications of ozone minihole formation in both hemispheres, J. Geophys. Res., 111, D02104, doi:10.1029/2005JD006333, 2006. James, P. M., Peters, D., and Waugh, D. W.: Very low ozone episodes due to polar vortex displacement, Tellus B, 52, 1123–1137, 2000. Newman, P. A., Lait, L. R, and Schoeberl, M. R.: The morphology and meteorology of southern hemisphere spring total ozone mini-holes, Geophys. Res. Lett., 15, 923–926, 1988. Schoeberl, M. R. and Krueger, A. J.: Medium scale disturbances in total ozone during southern hemisphere summer, B. Am. Meteorol. Soc., 64, 1358–1365, 1983. Serrano, A., Antón, M., Cancillo, M. L., and Mateos, V. L.: Daily and annual variations of erythemal ultraviolet radiation in the South-western Spain, Ann. Geophys., 24, 427–441, 2006. Stick, C., Kruger, K., Schade, N. H., Sandmann, H., and Macke, A.: Episode of unusual high solar ultraviolet radiation over central Europe due to dynamical reduced total ozone in May 2005, Atmos. Chem. Phys., 6, 1771–1776, 2006.