This study predicts cherry blossom (Prunus yedoensis) flowering in Japan during global warming periods. First, by developing current models for cherry blossom flowering, a model suitable for assessing the climate impact is constructed. This model can predict the dormancy breaking and flowering dates by temperature data alone at any points and for any periods. Applying this model to actual data for 25 years (1979-2003), the average RMSE (root mean squared error) of predicted flowering dates in comparison to actual ones at 36 points in Japan is 2.87 days.
An indicator of the southern border of flowering is also proposed. The flowering model is applied to projected future temperature based on the IPCC A2 scenario. The predictions for the years 2032-2050 and 2082-2100 indicate that flowering dates will become much earlier than at present in cold regions, while later along the coasts in warm regions. It also shows that cherry blossoms will not come out in Tanega-Shima and southern Kyushu, which are currently the southern flowering borders.
