climate Article The Influence of the Antarctic Oscillation (AAO) on Cold Waves and Occurrence of Frosts in the State of Santa Catarina, Brazil Maikon Passos A. Alves 1,*, Rafael Brito Silveira 1, Rosandro Boligon Minuzzi 2 and Alberto Elvino Franke 1 1 Applied Climatology Laboratory (LabClima), Federal University of Santa Catarina (UFSC), Trindade, Florianópolis 88040-900, Brazil;
[email protected] (R.B.S.);
[email protected] (A.E.F.) 2 Agricultural Climatology Laboratory (Labclimagri), Federal University of Santa Catarina (UFSC), Admar Gonzaga Str., Itacorubi, Florianópolis 88034-000, Brazil;
[email protected] * Correspondence:
[email protected]; Tel.: +55-48-999-264-326 Academic Editors: Valdir Adilson Steinke, Charlei Aparecido da Silva and Yang Zhang Received: 1 November 2016; Accepted: 24 February 2017; Published: 2 March 2017 Abstract: This paper examines the relationship between the Antarctic Oscillation (AAO), cold waves and occurrence of frosts in the state of Santa Catarina, Brazil, during the winter quarter. Research on this topic can assist different spheres of society, such as public health and agriculture, since cold waves can influence and/or aggravate health problems and frosts can inflict economic losses especially in the agricultural sector. For the purpose of this paper, cold wave is considered as the event in which the daily average surface air temperature was at least two standard deviations below the average value of the series on the day and for two consecutive days or more. The data on the average air temperature and frost occurrences are provided by the Company of Agricultural Research and Rural Extension of Santa Catarina/Center for Environmental Information and Hydrometeorology (EPAGRI/CIRAM).