Pelicans have been spotted wandering into Peruvian ports and pushing through urban streets, searching for food they can no longer find offshore. It’s a strange, almost disorienting sight — but it’s also one of the earliest visible signs of something much larger unfolding across the Pacific.
El Niño officially returned in June 2026. Even in its early stages, its ecological fingerprints are already showing up — not just on coastlines, but in satellite data streaming down from orbit, where NASA instruments are tracking changes the naked eye could never detect.
A familiar climate pattern returns — stronger this time
El Niño’s return wasn’t a surprise. Scientists had been watching the signals build for months. What’s notable now is the projected scale and duration: NOAA’s Climate Prediction Center puts a 97% chance on this event persisting through early spring 2027, with continued strengthening expected through the end of 2026.
Satellites have already confirmed the hallmark signatures — elevated sea surface temperatures and higher-than-normal sea surface height across the equatorial Pacific. These aren’t subtle readings. They’re the same patterns scientists tracked through previous events, now playing out in real time.
The effects reach far beyond the ocean. El Niño reshapes weather systems globally, contributing to desert flooding, delayed monsoons, and shifts in tropical cyclone formation. Some of the most consequential changes, though, happen quietly — beneath the surface, where the food web begins.
The ocean goes quiet: how El Niño starves phytoplankton
The mechanism is straightforward, even if the consequences aren’t. During El Niño, the easterly trade winds that normally blow across the equatorial Pacific begin to weaken, causing the warm surface layer to deepen — and shutting down the upwelling of cold, nutrient-rich water from below.
Phytoplankton depend on that upwelling. Without it, their primary nutrient supply disappears and populations decline sharply.
NASA’s PACE satellite captured this contrast directly. Comparing chlorophyll-a concentrations — a reliable proxy for phytoplankton abundance — between June 2025 (neutral conditions) and June 2026 (El Niño strengthening), the difference in the central Pacific, north of New Zealand, was substantial. Less green. Less life.
Oceanographers Matthew Kehrli and Graham Trolley at NASA’s Goddard Space Flight Center expect the deficit to grow. The changes “may manifest as a greater difference in values across the current region, as a broadening region of reduced surface chlorophyll-a concentration, or both, depending on the behavior of the equatorial trade winds.”
Ripple effects: from microscopic algae to fishing bans
Phytoplankton sit at the base of nearly every marine food chain in the Pacific. When they decline, the effects move upward fast — through zooplankton, to fish, to seabirds and marine mammals.
Peru’s anchovy fisheries rank among the most productive in the world, but they’re acutely sensitive to El Niño conditions. Warmer surface waters, reduced upwelling, and lower phytoplankton abundance have historically caused dramatic catch collapses. In 2026, Peru’s Ministry of Production suspended the fishery multiple times to protect remaining stocks. The pelicans wandering into ports aren’t just a striking image — they’re a measurable behavioral shift driven by coastal food scarcity, echoing patterns documented during the severe 2015–2016 El Niño.
After the disruption: the possibility of a rebound
El Niño’s ecological damage isn’t necessarily permanent. Research suggests that a post-El Niño “chlorophyll rebound” can occur — driven by higher iron concentrations in ocean currents and dust blown in from drier land areas across Central and South America. Crucially, this recovery doesn’t require a follow-on La Niña, though La Niña — which frequently follows El Niño events — can also elevate chlorophyll levels on its own.
The clearest historical example came after the strong La Niña of 1998–1999, which triggered a large phytoplankton bloom in the eastern Pacific and a dramatic rebound in fish populations. That recovery offered a reminder that marine ecosystems can show resilience, even if the timing and scale of any future rebound remain difficult to predict.
PACE: a new eye on an old phenomenon
What makes 2026 different from every previous El Niño is PACE. Launched in February 2024, NASA‘s Plankton, Aerosol, Cloud, ocean Ecosystem satellite is now collecting near-daily hyperspectral ocean color data globally — making this the first complete El Niño observed at this level of detail.
“The scientific community will be able to observe the 2026 El Niño with data across more wavelengths of light than ever before,” Kehrli and Trolley noted. That expanded spectral range means researchers can identify specific phytoplankton communities — not just total abundance — and track how individual species respond to shifting conditions. PACE’s sensors also measure plant pigment composition on land and monitor clouds and aerosols, both of which El Niño disrupts. As the event strengthens into late 2026 and early 2027, that dataset will grow into something scientists have never had before: a full-resolution portrait of how a major climate event reshapes life across Earth’s interconnected systems.
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