摘要
以日平均气温低于23.0℃、持续3d或3d以上的低温过程作为出现“23型”寒露风的指标,根据谐波分析原理,对福州1951—1990年的“23型”寒露风初日进行统计分析,建立了谐波模式:y_=30.75+3.73cos(27t_)-4.38sin(27t_)+2.22cos(18t_)+4.37sin(18t_)-1.04cos(9t_)+4.59sin(9t_)。利用这个模式,分析福州“23型”寒露风变化趋势及其对连作晚稻生产的影响。
On the principle of harmonic analysis and using less than 23.0 degrees centigrade on the average a day for three consecutive days or above three days as the norm of the 'Type 23'low autumn temperature, the paper establishes the harmonic pattern [y_i=30.75 +3.73cos(27t_i)-4.38sin(27t_i)+2.22cos (18t_i)+4.37sin (18t_i)-1.04cos(9t_i) +4.59sin(9t_i)]on the basis of statistical analysis of the dates of the first day of the 'Type 23'low autumn temperature in Fuzhou from 1951 to 1990, and analyses the changable tendency towards the first day of the 'Type 23' low autumn temperature in Fuzhou and its influence on the continuous cropping late rice production according to the pattern.
关键词
寒露风
谐波分析
福州
low autumn temperature
harmonic analysis
Fuzhou
