# Global ocean temperature records 2026 – July peak

> Live situation record from CLSTR: https://clstr.news/situations/global-ocean-temperature-records-2026
> Updated: 2026-08-23T04:36:41.000Z. Sources: 8. Developments: 4.

Global sea-surface temperatures reached unprecedented levels in mid-2026. In June, temperatures hit 20.98 °C, surpassing the previous June record. This was followed by a record-breaking streak of over 50 consecutive days where global average temperatures remained near 21 °C. By 21 July, temperatures peaked at approximately 21.11 °C, driven by a strong El Niño event and greenhouse-gas emissions.

July 2026 tied with 2024 as the second warmest July on record, with average temperatures 1.47 °C above pre-industrial levels. During the first half of the year, approximately 82% of the world's oceans experienced marine heatwave conditions. Notable extremes occurred in the tropical Pacific, the Atlantic near Europe, and the western Mediterranean.

Regional impacts include significant warming in Turkey’s seas. Long-term data shows air and water temperatures rose from 12.7 °C in the 1970-80s to 14.4 °C in 2014-25. Mediterranean temperatures rose by 1.3 °C to 22.3 °C, while the Aegean and Marmara seas warmed 0.8 °C and 2.2 °C, respectively.

Scientists warn that these sustained temperatures increase risks of severe heatwaves, tropical cyclones, and sea-level rise. In response to the threat of coral bleaching, researchers at the Hawaiʻi Institute of Marine Biology and the University of Hawaiʻi are investigating assisted evolution strategies, such as selective breeding, to help coral populations adapt to warmer waters.

## Timeline

### 2026-08-23: Ocean temperatures reach historic highs amid rising marine heatwaves

Global ocean temperatures hit record highs in July 2026, driving marine heatwaves. In Hawaii, scientists are using selective breeding to develop heat-resistant corals to combat bleaching.

2 sources. https://clstr.news/cluster/ocean-temperatures-reach-historic-highs-amid-rising-marine-heatwaves

### 2026-07-25: Global Ocean Surface Temperatures Set 50‑Day Record

Ocean surface temperatures have stayed at record‑high levels for over 50 days, averaging ~21 °C, highlighting amplified heat absorption amid global warming and El Niño, with potential impacts on weather and sea

2 sources. https://clstr.news/cluster/global-ocean-surface-temperatures-set-50day-record

### 2026-07-25: Turkey and Global Oceans Hit Record Temperatures Amid Rising Heat

Turkey’s seas have warmed up to 2 °C over 55 years, while global ocean temperatures set new records, driven by El Niño and ongoing climate change.

2 sources. https://clstr.news/cluster/turkey-and-global-oceans-hit-record-temperatures-amid-rising-heat

### 2026-07-04: June 2026 Global Sea Temperatures Reach Record High

June 2026 saw global sea‑surface temperatures hit a new record of 20.98 °C, while atmospheric temperatures rose +0.46 °C above the 1991‑2020 average, driven by greenhouse gases and a looming El Niño, raising up

2 sources. https://clstr.news/cluster/june-2026-global-sea-temperatures-reach-record-high

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Cite as: Global ocean temperature records 2026 – July peak. CLSTR, https://clstr.news/situations/global-ocean-temperature-records-2026