545463.fig.006a
(a)
545463.fig.006b
(b)
545463.fig.006c
(c)
545463.fig.006d
(d)
Figure 6: Partial correlation coefficient for JFM cyclone frequency versus PNA (excluding ENSO and NAO). Correlation (shaded). 2-tailed 90% significance (hatched) for (a) NCEP1_5801, (b) ERA40_5801, (c) NCEP1_7910, and (d) NCEP1_5078.