Figure 5 | Scientific Reports

Figure 5

From: Formation Mechanism for 2015/16 Super El Niño

Figure 5

(a) Scatterplot of the Jan–Jul (0) accumulated WWE index and the precursory D′ signal for each El Niño event during 1979–2015. Here the precursory D′ signal is estimated by the Aug–Nov(−1) averaged sea surface height anomaly (a proxy of D′) over the tropical western Pacific (130°E–180°, 10°S–10°N). (b) same as (a) but for the accumulated “W + E” index, which is the summation of the accumulated WWE and accumulated EWE index. It shows that when taking into account the role of easterlies, the spreading between 2015 EN and other ENs revealed by the “W + E” index (Fig. 5b) resembles that revealed by the WWE index alone (Fig. 5a). The specific calculation of the accumulated WWE, EWE, and “W + E” index is introduced in the method section. This figure was generated by the licensed Microsoft Excel.