Section 15.3: Multivariate AR(l) Process
293
Figure 15.1: Two complex POPs (in relative units) derived from a combined
dataset including anomalies of the surface wind and SST and the strataspheric zonal wind. The imaginary (real) part of a POP is indicated by the
thick (thin) line. (From Xu, 1993).
POP'
3
2
0
-2
-3
90'E
180'
9O"E
180'
5020
longltude
mb
2
POP2
o ~-:--I--\'
-1
4~ __ ~ ____ ~ ____ ~~~ ______ ~ ____ ~
9O"E
180"
9O"E
Iongltude
5020
mb