Projections are that a strong El Niño is on the way. An El Niño is a natural release valve for ocean heat. It starts with shifts of swirling ocean currents and winds over the Pacific. The result is that huge stores of tropical ocean heat surges from the Western Pacific in the area between Australia and Indonesia northward to Japan. The ocean heat then spills into the atmosphere in pulses that change weather patterns, reroute high-elevation winds, raise global temperatures, bleach coral reefs, and disrupt fisheries and ocean ecosystems. The impacts on continents include intensified rainstorms and flooding in some regions but extreme heat, drought, and wildfires in others.
The expectation is that there will be a strong El Niño during the next 12 to 18 months. An El Niño is a temporary phenomenon, but its impact on the climate might not be. The planet’s average annual temperature has already reached dangerously high levels and a strong El Niño could push it past the 1.5 Celsius threshold that experts believe to be a turning point for potentially irreversible climate impacts.
Estimates are that a strong El Niño over the next 12 to 18 months could drive the global average temperature to about 1.7 degrees above the preindustrial level. It is doubtful that the world will meaningfully cool back down below the 1.5-degree mark after the El Niño fades. That threshold is not like falling off a cliff, but it is the point when the edge starts crumbling. There can be rapid changes to relatively stable systems of forests, water, rain, and temperature that have been typical for people and ecosystems for millennia.
