SIGNAL DETECTION OF GLOBAL CLIMATE CHANGE AND EXTERNAL FORCING FACTORS

In this paper,we displayed one-dimensional climate signals,such as global temperaturevariation,Southern Oscillation Index and variation of external forcing factors,on a two-dimensional time-scale plane using compactly supported wavelet decomposition.Using the lag-correlation analysis method,and interpretative variance analysis method,and phase comparisonmethod to the wavelet analysis result,we not only gained the variation on different scales to theglobal temperature and El Nino signals,the location of the jump point and intrinsic scale of theseseries,but also indicated the magnitude,extent and time of the effect of external forcing factors onthem.We also put forward reasonable explanation to the main variation of recent 140 years.