September 2, 2026 — In the north-east Pacific Ocean, an immense and persistent heatwave is wreaking havoc on marine life and weather patterns.
“It’s a really bright red eyeball in the Pacific,” says Andrew Leising, a research oceanographer at the US National Oceanic and Atmospheric Administration (Noaa). “It’s huge, it stretches across the whole [ocean].” The Pacific heatwave, which formed in May 2025, is already bringing surface temperatures 3-4C (5.4-7.2F) above average for this time of year, according to Leising.
Add to that: a massive warming pattern known as El Niño is brewing further south. El Niño is a weather phenomenon that pushes up global temperatures, and it is also supercharging Pacific Ocean warming. It is expected to intensify this autumn to become the strongest El Niño in living memory.
This combination of a massive marine heatwave and a “super El Niño” is rarely seen. Here are five impacts we can expect to see – and where they will happen.