It may be that the observed phenomenon of more frequent and stronger El Niño events occurs only in the initial phase of the global warming, and then (e.g., after the lower layers of the ocean get warmer, as well), El Niño will become weaker.
可能现在观测到的更强更频繁的厄尔尼诺事件只是发生在全球变暖的早期阶段，然后（比如在海洋低层也变暖后），厄尔尼诺将可能变得比现在要弱些。