NASA's Sea Level Data Shows 2026 Tracking Like 1997 — Here's the Catch

NASA's Sentinel-6 Michael Freilich satellite shows a Pacific sea-level pattern in June 2026 that scientists say resembles 1997 at the same calendar point. But the comparison isn't as clean as the headlines suggest.

Written by Chris Corwin, IAMElNino.com · Drafted with AI research assistance, fact-checked against NOAA CPC source data, and reviewed before publication.

Sea surface height might sound like an odd thing to track for an ENSO story, but it's one of the most reliable physical proxies available: when ocean water warms, it expands and the surface literally rises. NASA's Jet Propulsion Laboratory uses exactly this signal — measured by the Sentinel-6 Michael Freilich satellite — to track the buildup of heat ahead of El Niño's surface arrival.

Sentinel-6 Observation — June 8, 2026

Western Pacific patternVisually similar to 1997

Eastern Pacific patternLagging 1997's pace

Kelvin waves observedFewer than 1997 at same stage

TrajectoryMore warm Kelvin waves approaching

What Researchers Actually Said

According to JPL sea level researcher Severine Fournier, conditions in the western Pacific on June 8 "looked similar to those from the same time in 1997" — the year of one of the strongest El Niño events on record. That's the headline-grabbing part.

But the more careful read is the second half of the finding: warm conditions in the eastern Pacific have lagged behind 1997's pace, with fewer Kelvin waves — the slow-moving subsurface heat pulses that eventually surface and drive El Niño — having arrived there by the same date. More are reportedly on the way, which is consistent with the broader Kelvin wave activity feeding this year's event.

Why the Distinction Matters

It's tempting to round "looks like 1997 in the west" up to "this will be as strong as 1997." That's not what the data says yet. Fournier's own assessment was careful: "For now, it looks like it's going to be a big one — more so than I would have said last week — but we still need more observations to know what's going to happen."

The honest takeaway: the setup resembles a major event. Whether the eastern Pacific catches up to that western Pacific signal over the coming weeks is the open question that will determine whether 2026 ends up rivaling 1997-98 or settling into a strong-but-not-historic event.