EFFECT OF ARCTIC ICE COVER ON THE MONTHLY TEMPERATURE AND PRECIPITATION IN CHINA

Filtering technique, extended empirical orthogonal function (EEOF), spectrum distribution function and correlation analysis have been employed to study the relationship between arctic ice cover (AIC) and monthly mean temperature and precipitation in China. The function of power spectrum density shows that not only a semi-annual and an annual oscillation but also a quasi-biennial oscillation can be found in AIC area index series, especially in June, September and November. During the period of analysis, it can also be found that there exists a good correlation between the El Nino events and the AIC area index. An analysis on the EEOF of AIC and the temperature over China exhibits some significant temporal-spatial patterns and a better time-lag interrelationship between them. The results from the correlation analysis indicate that the variation of AIC area has a significant influence on the temperature and precipitation in subsequent months over China. In addition, it experiences a quasi-biennial low-frequency oscillation and displays to certain extent some features of propagation.