The Mediterranean Sea is heating up faster than ever: what this means for Israel

A new study published in the journal Geophysical Research Letters shows that the Mediterranean Sea is warming and becoming saltier faster than previously thought, with changes reaching depths of 3,000-4,000 meters. Accelerated warming has been recorded in the central and eastern parts of the sea, including waters off the Israeli coast, which could affect the marine ecosystem and the operation of desalination plants.

A new study published on September 23 in the journal Geophysical Research Letters shows that the Mediterranean Sea is warming and becoming saltier faster than previously assumed. Scientists Elena Terzić and Ivica Vilibić from Croatia's Ruđer Bošković Institute analyzed temperature and salinity measurements taken across the Mediterranean Sea from 1950 to 2025. It was found that changes are not limited to the surface—they reach depths of 3,000-4,000 meters. In recent years, the upper 100-meter layer of the sea has become on average about two degrees Celsius warmer than in 1950-1999. Since 2000, surface waters have warmed by about half a degree per decade—two to three times faster than the surface waters of the global ocean. Accelerated changes have been traced to a depth of about 2,500 meters. For Israel, this study is significant because waters off the Israeli coast are already among the warmest and saltiest in the region. Further warming could change living conditions for fish: some species will find it harder to survive, while heat-loving invasive species from the Red Sea may spread more widely. The state of the sea is also important for the operation of desalination plants, although the study does not predict their shutdown or an increase in water costs. Scientists note that the Mediterranean Sea could serve as a 'micro-model' of what will happen to the global ocean, since water moves between the surface and depth about ten times faster there.