(a)
(b)
(c)
(d)
Figure 3: Difference in precipitation (%) ((a), (b)) and severe drought frequency (per/100 years) ((c), (d)) over the East European Plain in the westward QBO phase as compared to the eastward phase in May (on the left) and in June (on the right) in the period 1953–2011. Significant differences are shown inside the black contours.