Global oceans experience record heat in June, driven by El Niño and climate change

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🗞️ Driving the news: Global oceans reached record surface temperatures in June 2026, averaging 20.98°C, surpassing the previous highs of 2023 and 2024
• Copernicus Marine Service reports that the first half of 2026 was the second-warmest on record, with prolonged marine heatwaves affecting vast ocean regions

🔭 The context: The onset of a potentially strong El Niño is compounding long-term climate warming, releasing heat into the atmosphere and affecting global weather patterns
• The Pacific, Mediterranean, and equatorial regions recorded unprecedented ocean temperatures, contributing to extreme weather events, coral bleaching, and ecological stress

🌍 Why it matters for the planet: Hotter oceans intensify tropical cyclones, rainfall, and droughts while accelerating sea level rise through thermal expansion
• Marine heatwaves threaten coral reefs and marine biodiversity, disrupt fisheries, and exacerbate the warming of the global climate system

⏭️ What’s next: Scientists warn that sea temperatures may climb further as El Niño develops, likely pushing global ocean heat and atmospheric temperatures to new records through 2026 and 2027
• Monitoring, mitigation, and adaptation efforts are critical to managing ecological and climate risks

💬 One quote: “The world’s oceans are in a deepening crisis, absorbing excess heat and raising the stakes for both marine ecosystems and human societies.” – Copernicus Marine Service spokesperson

📈 One stat: 82% of the world’s oceans experienced marine heatwaves in the first half of 2026, the second-largest extent on record

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