The Mediterranean sea recorded above-average temperatures during 2024 and 2025

The surface temperature of the Mediterranean Sea recorded values above the climatic average during 2024 and 2025, according to data from the Spanish State Meteorological Agency (Aemet). The comparison is made with the reference period 1991–2020, commonly used to assess thermal anomalies and the evolution of climate change.

Aemet stated on the social network X that the Mediterranean Sea temperatures only briefly approached normal values, specifically at the end of July and the beginning of August, as well as in mid-October of both years, remaining above usual levels for the rest of the time.

This situation forms part of a broader global trend. Last Friday, January 9th, the scientific journal Advances in Atmospheric Sciences reported that Earth’s oceans stored more heat in 2025 than in any other year since modern records began, equaling the all-time maximum reached in each of the previous nine years.

According to the study, ocean warming does not occur uniformly. The areas with the greatest temperature increases are the tropical ocean, the South Atlantic, the North Pacific, and the Southern Ocean, highlighting uneven warming on a planetary scale.

The research combines data from major international data centers and independent research groups, including Copernicus Marine (the European Earth observation program), the Institute of Atmospheric Physics of the Chinese Academy of Sciences, and NOAA/NCEI of the United States, as well as an ocean meta-analysis (CIGAR-RT) with contributions from Asia, Europe, and the Americas.

All analyses agree that in 2025 the Ocean Heat Content (OHC), one of the most reliable indicators of long-term climate change, reached the highest level ever recorded, confirming the sustained increase in heat accumulated in the oceans.

In the Atlantic, waters surrounding the Canary Islands also generally showed temperatures above the 1991–2020 average. However, during 2025 there were some episodes of cooler-than-normal waters, particularly in early March, between late September and mid-October, and again in December.