June 2026 Global Sea Temperatures Reach Record High

In June 2026 the average global sea‑surface temperature reached 20.98 °C, surpassing the previous June record of 20.89 °C, according to the Copernicus Marine Service. The same month the satellite‑derived global average temperature in the lower atmosphere was measured at +0.46 °C above the 1991‑2020 baseline, indicating an accelerating warming trend.

Experts linked the unprecedented ocean heat to the combined influence of rising greenhouse‑gas concentrations and an emerging El Niño cycle. Copernicus Climate Change Service head Carlo Buontempo warned that the interaction of warming oceans and El Niño is likely to trigger further record‑breaking heat, while oceanographer Simon van Gennip noted that 2026 appears on track to become one of the warmest years on record. The heightened sea temperatures are expected to intensify tropical cyclones, threaten marine ecosystems and contribute to sea‑level rise.