Fig. 6: Schematic mechanism of SPB asymmetry.
From: El Niño and La Niña asymmetry in short-term predictability on springtime initial condition
The anomalous SST warming will cause strong westerly anomalies, strong zonal current anomalies and further strengthen the initial SST warming. As such, a larger El Niño growth rate will lead to a stronger ZA positive feedback, a weaker SPB and higher El Niño predictability. Nevertheless, the easterly anomalies caused by SST cooling are relatively weaker compared to westerly anomalies, so does the ZA feedback and La Niña growth rate. Hence, it leads to a stronger SPB and lower predictability of La Niña.
