Study on the Analysis of "Type 20" periodic Pattern of Low Temperature during Autumn Season in Fuzhou and Its Application

Using the average daily temperature which is less than 20℃ for consecutive 3 days or more as the norm occuring "type 20" low temperature during autumn season, a periodic pattern modelled as Yi = 50.231+ 5.037Cosπ/9ti - 2.831Sinπ/9ti has been established via through the analysis of periodic pattern of initial days during autumn season from 1951 to 1989 in Fuzhou area. The dynamic change of low temperature and its influence on the production of late rice during autumn season in Fuzhou area has been analysed according to the model.