Fig. 4
Differences of composites for May–September averaged a geopotential height b specific humidity anomalies at 850 hPa between years with Nino3.4 index in the preceding January to March greater than 0.5 and smaller than -0.5. The contour interval is 2 m for a and 0.1 g kg−1 for b. Contours for positive values are in red, whereas those for negative values are in blue. The zero contour is omitted. The shaded areas indicate that the value is different from zero at a significance level of 0.05 according to a Student’s t-test
