This summer marked the hottest on record in the Aegean, Ionian and Cretan seas, with water temperatures surpassing 28 Celsius in extensive areas.
Scientists have documented a significant, long-term rise in sea temperatures, averaging an increase of 0.59C per decade. The rise, attributed to climate change, was particularly striking in deeper waters, where temperatures were notably warmer than in previous years, disrupting cooling effects from deeper layers.
The intensity of marine heatwaves also reached unprecedented levels in 2024. While the frequency of these heatwaves was not particularly high, their duration and cumulative intensity exceeded previous records, doubling the highest levels seen in 2018.
Researchers note that atmospheric temperatures were extremely high, leading to more heat transfer from the air to the sea. Additionally, reduced freshwater inflow from the Black Sea to the Aegean exacerbated the heat buildup. Rising sea temperatures have significant biological, environmental and economic consequences, such as the destruction of mussel farms in Thessaloniki due to thermal shock.
