Global Ocean Surface Temperatures Outside Polar Regions Reached Record High on June 21

Global ocean surface temperatures outside polar regions reached a record high on June 21, NBC News reported. The Copernicus Climate Change Service recorded 20.86 °C that day, exceeding the previous June records of 20.83 °C set in 2023 and 2024. The Copernicus Marine Service recorded 21 °C, surpassing prior marks by 0.1 °C.

NBC News reported that more than 46 million people in the United States remained under extreme heat alerts issued by the National Weather Service as of July 1. Temperatures topped 90 °F in Chicago on June 29. The National Weather Service warned of dangerous heat building across the central and eastern United States, with highs expected to reach the mid-to-upper 90s and some locations exceeding 100 °F through the July Fourth weekend.

More than 1,300 excess deaths linked to high temperatures were recorded in Europe between June 21 and June 28, NBC News reported. France recorded approximately 1,000 more deaths than expected in the week ending June 28 during its heat wave.

He added that the rising temperatures could mark the beginning of a new phase and that the world could be heading into uncharted territory. Richard Allan, professor of climate science at the University of Reading, stated that oceans absorb more than 90 percent of excess energy on Earth primarily caused by burning fossil fuels.

Pierre-Yves Le Traon, scientific director of Mercator Ocean International, stated that it is important to continue monitoring rising ocean surface temperatures, adapt, and reduce greenhouse gas emissions.

Tedros Adhanom Ghebreyesus stated on June 28 that the once-in-a-generation heat wave is now occurring nearly annually, driven by climate change. He also stated that Europe is the fastest-warming continent, heating at twice the global average.