ACPD Atmospheric Chemistry and Physics Discussions ACPD Atmos. Chem. Phys. Discuss. 1680-7375 Göttingen, Germany 10.5194/acpd-12-17443-2012 A new El Niño-Southern Oscillation forecasting tool based on Southern Oscillation Index Varotsos C. A. 1 Tzanis C. 1 Climate Research Group, Division of Environmental Physics and Meteorology, Faculty of Physics, University of Athens, University Campus Bldg. Phys. V, Athens 15784, Greece 16 07 2012 12 7 17443 17463 Copyright: © 2012 C. A. Varotsos 2012 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://acp.copernicus.org/preprints/12/17443/2012/acpd-12-17443-2012.html The full text article is available as a PDF file from https://acp.copernicus.org/preprints/12/17443/2012/acpd-12-17443-2012.pdf

An exploration of the temporal evolution of the El Niño Southern Oscillation (ENSO) during January 1876–November 2011 by means of a new time domain called <i>natural time</i> reveals that the major ENSO events provide precursory signals that are maximized in a time window of almost two years. This finding improves the accuracy of the short-term prediction models of the ENSO extreme events, preventing thus from its disastrous impacts in advance.

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