Core Insights - The Mediterranean Sea is experiencing significant warming trends due to climate change, posing serious threats to marine ecosystems and the sustainability of fisheries [1][2]. Group 1: Temperature Changes - From 1982 to 2023, the average annual sea surface temperature in the Mediterranean increased by 0.041 degrees Celsius [1]. - Between 1991 and 2020, the surface temperature of Greek waters rose approximately 1.5 degrees Celsius, with the upper 200 meters of water warming by about 1.2 degrees Celsius and depths of 200 to 800 meters warming by around 0.9 degrees Celsius [1]. - Even at depths of 4000 meters, a temperature increase of about 0.2 degrees Celsius has been observed [1]. Group 2: Ecological Impacts - The warming of the Mediterranean is leading to multiple ecological issues, including changes in the structure and function of phytoplankton populations, which are foundational to the marine food chain [1]. - Invasive species such as lionfish are rapidly expanding due to increased sea temperatures, which is squeezing the living space of native species [1]. - Coral and sponge populations are experiencing mass mortality during heatwaves, leading to overall degradation of the ecosystem [1]. Group 3: Impact on Aquaculture - The rising sea temperatures are adversely affecting aquaculture, particularly species like mussels that have limited capacity to cope with extreme heat and cannot easily migrate, resulting in significant losses during heatwaves [1].