click image to enlarge

[chart] Probability of flooding in 26 PNW rivers based on ENSO/PDO phase and river type.

Probability of flooding in 26 PNW rivers based on ENSO/PDO phase and river type. Same as in Figure 3 but separated by type of basin: rain-dominated, transient snow, and snow-dominated. Snow-dominated basins are most sensitive to both ENSO and PDO, with the greatest separation between categories where ENSO and PDO are in the same warm or cool phase. Transient snow basins show some sensitivity to ENSO but less to PDO. The rain-dominated basins seem to show less sensitivity to climate variation, although the results are probably not statistically significant because of the small sample size (n=3).