What Does EOF Analysis do?
	q In brief, EOF analysis uses a set of orthogonal functions (EOFs) to represent a time series in the following way: q Z(x,y,t) is the original time series as a function of time (t) and space (x, y).      EOF(x, y) show the spatial structures (x, y) of the major factors that can account for the temporal variations of Z.      PC(t) is the principal component that tells you how the amplitude of each EOF varies with time.