Summer advances and the classic refreshing feeling when entering the waters of the Mediterranean is something that little by little we no longer feel in the same way. The reason is none other than that the water continues to heat up year after year and exceed record numbers, which not only makes us feel less cool when bathing, but is also causing alterations in our climate, reaching the point that it could even exceed the temperatures of the Caribbean Sea during this summer.
Setting record. The data recorded on the Spanish coasts are especially compelling, and here the oceanographic buoys are our best ally by serving as a source of these measurements and which have been recording exceptional figures.
To put ourselves in context of what is happening in our waters, we can look at the Bay of Pollença in Mallorca, where one of the buoys detected a water surface temperature of 32.1 ºC.
The reason. Here the main culprit is undoubtedly the constant train of heat waves that is leaving the water of the western and central Mediterranean above 30 ºC in many of its sectors. But in addition to affecting the marine ecosystem, these extreme temperatures on the ocean surface contribute a greater amount of water vapor to the air, which increases relative humidity to levels between 80% and 90% and destroys thermal comfort in the form of torrid nights.
And it is not something specific, but rather it is an inertia that we are moving towards, as confirmed by the Copernicus Marine Service, which points out that during the first half of 2026 the Mediterranean experienced an average surface temperature of 18.07 ºC. This makes the semester between January and June the third warmest ever recorded, only surpassed by 2024 and 2025, and the same European organization points out that marine heat waves have affected about 82% of the global ocean, consolidating the Mediterranean as one of the highest risk hotspots worldwide.
From space. Satellites have also detected these anomalies that confirm in another way the records that our Mediterranean is facing. Specifically, the ESA recorded on June 29, 2026 that the Mediterranean suffered anomalies in its surface temperature of up to 8 °C above the average for the period 1991-2020. If we are more specific, the wildest temperature increases were located off southern France and around the islands of Corsica and Sardinia, as well as on the Italian peninsula.
Globally, Copernicus detected that on June 30 the global sea surface temperature anomaly was +0.5 °C, the highest value ever recorded for that calendar date. All this goes hand in hand with a suffocating atmospheric context, since the Copernicus C3S service documented that June 2026 was the second hottest June globally, reaching an average temperature of 16.54 °C, which is 1.39 °C above the pre-industrial level.
The Mediterranean takes the worst part. The average temperature in the Mediterranean area has already risen approximately 1.5 °C since the pre-industrial era and this warming is progressing at a rate 20% faster than the global average. These figures are very serious, since future projections require urgent action, since it is expected that the Mediterranean could warm up to 5.6 ºC by the year 2100, varying depending on the final volume of our emissions.
In | AEMET says it bluntly: in the Mediterranean it no longer makes sense to talk about a “tropical night” because almost all of them are.
