June 2025 was a red-alert month for the waters of the Mediterranean Sea. The average surface temperature was 24.3°C, the highest recorded for this month in the previous ten years. One degree above the average for the period 2015-2024, a tangible sign of a climate crisis that continues to advance relentlessly. The Tyrrhenian Sea averaged 25.1°C, while the Adriatic averaged 24.1°C, with the exception of the eastern coasts of Montenegro and Albania, where the waters were slightly less warm. Legambiente's Goletta Verde raised the alarm by organizing a symbolic demonstration along the Adriatic coast last weekend, with the banner "It's not hot. It’s a climate change” to highlight how global warming is also altering the marine ecosystem. The environmental organization has updated satellite pictures from the European Copernicus service, focusing on the Adriatic Sea, where the Goletta Verde's summer journey began on June 23. The average sea temperature throughout Italy's 1,000-kilometer coastline, from the Slovenian border to the Strait of Otranto, was 24.6°C, the highest in June since 2015. Even the temperature peaks are alarming: the maximum recorded was 29.8°C, which is 1.9°C higher than the average of the extreme values observed during the same period. Even the minimum value of 19.3°C was higher than the historical average and is the third highest among the minimum values recorded in the past ten years. The Goletta Verde will continue its journey over the Tyrrhenian Sea to Liguria, arriving on August 9, to continue monitoring the health of the Italian sea. A project that, once again, highlights an environmental crisis that cannot be ignored.