Melo-Abreu, J. Paulo deCordeiro, António ManuelMaia, Frederico de BarrosBarba, Nuno GeraldesBarros, FlávioRibeiro, A.C.Neves, AlcindaVilallobos, FranciscoNunes, LuísCardoso, Rita M.2014-05-072014-05-072012Melo-Abreu, J.P.; Cordeiro, A.M.; Maia, F.B.; Barba, N.G.; Barros, F.; Ribeiro, A.C.; Neves, A.; Vilallobos, F.; Nunes, L.F.; Cardoso, R.M. (2012). Predicting olive phenology in Portugal in a warming climate. In 12th Congress of European Society for Agronomy. Helsinki, Finland978-952-10-4323-9http://hdl.handle.net/10198/9467Prediction of flowering of olive trees should account for chilling requirements, using an appropriate chilling unit for the accounting of chilling accumulation. After chilling requirements are satisfied, dormancy break takes place. Thereafter, the trees enter the forcing phase, in which the thermal time approach is used, but an appropriate base temperature must be determined. Such a model was developed, calibrated and validated for many olive cultivars (De Melo-Abreu et al., 2004). After flowering, the occurrence of developmental stages may be predicted using a thermal time approach, but for warm regions a saw-tooth model, which is a model that reduces the effect of supra-optimal temperatures, is mandatory (Garcia-Huidobro et al., :1.982). According to the simulations of the model HadCM3, developed by the Hadley Centre, global climate warming will result in average temperature anomalies in winter, in Continental Portugal, of about 2°C, in SRES scenarios 81 and 82, 3°C in scenario A2, and 4 °C in scenario A:tFI, by the end of XXI century. (Miranda et al., 2006). In this study, we discuss the prediction of flowering and subsequent phenological stages and calculate and map the times of occurrence of flowering under three warming scenarios. No flowering or abnormal flowering events are also predicted.engconference object