Record ocean heat persists for 100 days as El Niño intensifies

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🗞️ Driving the news: The global ocean recorded 100 consecutive days of record-high average sea-surface temperatures between June 2 and September 10, according to Climate Reanalyzer data
• Scientists attribute the exceptional heat primarily to human-driven climate change, with the current El Niño adding further warming

🔭 The context: Global ocean temperatures reached about 21.18°C between August 22 and 27, while the ocean absorbed an estimated 23 zettajoules of heat in 2025 , more than 43% above 2024
• Scientists expect the current El Niño to peak toward the end of 2026 and continue into 2027, although the longer-term warming trend is driven by greenhouse gas emissions

🌍 Why it matters for the planet: Persistent ocean warming is shifting marine ecosystems, increasing risks to coral reefs and fisheries, and affecting weather patterns and coastal heat
• Warmer seas can also intensify land-based heatwaves and increase humid-heat risks for human health

⏭️ What’s next: Scientists expect ocean temperatures to remain elevated in the near term as El Niño strengthens
• Reducing greenhouse-gas emissions remains the central measure identified by experts to slow the underlying ocean-warming trend

💬 One quote: “Ultimately, we need to cut emissions. That is the key thing here.” — Pickerell, World Resources Institute

📈 One stat: 100 days — the consecutive period from June 2 to September 10 during which global ocean temperatures exceeded the same-day record for every year since 1982.

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