Every sea, gulf and bay is connected. We map it whole, using the Spilhaus projection, and use real satellite data to show what it's doing right now.
Right now it's in a record El Niño. Each number on this page comes with a source, and anything still preliminary is labelled.
NOAA's weekly Niño-3.4 index for the week of Oct 7. That's the highest since the weekly series began in 1990. The previous high was +3.0 °C in Nov 2015.
NOAA CPC weekly OISST, 1991–2020 baseThat's how much earlier in the season than 2015 this El Niño passed the old weekly high. 2015 only reached +3.0 °C on Nov 18.
NOAA CPC weekly OISSTChlorophyll off Peru, Sep 12–Oct 4. It's the lowest for those dates since 1998, about 30% below the previous low (2017). Warm water is shutting down the upwelling that feeds one of the world's great fisheries.
Copernicus GlobColour L4, box 6–14°S, 81–76°W. Recent days are interim data.Average sea-surface temperature from 60°S to 60°N on Oct 10. It's the warmest for that date in 45 years of satellite data (1982–2026).
NOAA OISST v2.1A Kelvin wave, a bulge of sea level, crossed the Pacific from 176°E (Jul 22) to 264°E (Aug 31) and carried warm water toward South America.
Copernicus DUACS sea-level anomaly, 2°S–2°NShare of the world's reefs at coral-bleaching Alert Level 1 or higher on Oct 10. That's 3rd for the date, behind 2023 and 2024. We report the non-records too.
NOAA Coral Reef WatchHow to compare: NOAA's official monthly Niño-3.4 for September was +2.1 °C, which is a different measure from the weekly one. Data less than 15 days old can still be revised. NOAA gives an 83% chance that Oct–Dec will be a "historic" event (CPC, Oct 8).
Daily sea-surface temperature anomaly from Aug 1 to Oct 10, 2026. Water about 7–8 °C above normal is pressed against the coast. The outlined box is where we measured chlorophyll: the warm water has choked off the cold, nutrient-rich upwelling, and plankton there is at its lowest for the season since 1998 (preliminary).
NOAA OISST v2.1, 1971–2000 baseline. The box covers 6–14°S, 81–76°W.
Sea level along the equatorial Pacific from Jul 12 to Oct 12, with each day's recent 45-day average removed. Follow the warm streak along the equator as it runs east toward South America. It's a Kelvin wave, the way El Niño carries heat across an ocean, moving at about 3.0 m/s.
Copernicus DUACS sea-level anomaly. Color scale ±10 cm.
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Point your phone at the map to see today's ocean on it. This is an early demo.
We use public data and don't smooth it: every map is drawn at the data's native resolution. Comparisons keep their own baseline and are never mixed. Each claim is checked against a second source before it's posted. If something isn't a record, we say so.
The map is the Spilhaus projection (1942), which centers the oceans instead of the land, so the sea reads as the single body it really is.
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