THE IDENTIFICATION OF THE VOLCANIC SIGNAL IN GLOBAL SURFACE TEMPERATURE RECORDS

In an attempt to clearly separate the volcanic signal,we use a mixture of principal component analysis(PCA) and superposed epoch analysis to identify volcanic signal in the global surface temperature field.In this way,the spatial and temporal pattern of volcanic signals is identified in the global surface temperature records.Our results show that the strongest ENSO and volcanic signals are related with the first and the third principal components respectively.Both ENSO and volcanic signals have responses in the second principal component.