The effects of the climate crisis on the Mediterranean Sea

With temperatures rising 20% faster than the global average and sea levels expected to rise by more than one meter by 2100, the Mediterranean is becoming the fastest warming and most saline sea on our planet. 

The WWF report “The Climate Change Effect in the Mediterranean: Stories from an overheating sea” highlights the six main impacts that climate change has on all marine biodiversity and the extent of the resulting changes in key fish species and habitats, with consequences for the livelihoods of local communities:

1. The tropicalization of the eastern Mediterranean is spreading westward as the average water temperature rises, threatening ecosystems and economies.
2. Highly destructive invasive species (especially rabbitfish and lionfish), driven by the increase in average temperature, are spreading in the Mediterranean, devastating native ecosystems.
3. In the Mediterranean, an unprecedented number of jellyfish bloom every year, disrupting fishing activities and overwhelming tourist beaches.
4. The warming of the waters and the rising sea levels are threatening the survival of vital Posidonia meadows, with disastrous consequences for biodiversity and “blue carbon”.
5. Extreme weather events are destroying many coral species, which until now have played a key role in numerous Mediterranean ecosystems.
6. The sudden mass mortality of Pinna nobilis may be linked to the warming of the Mediterranean.

There is a dangerous relationship between climate impacts and current human pressures on marine life. Overfishing, pollution, coastal development, and shipping have already drastically reduced the ecological resilience of our sea—its ability to regenerate. 

The cases presented in the report clearly show the strong link between climate and ocean. But above all, they highlight the need for better marine protection to restore biodiversity and fish stocks and rebuild the resilience of our sea. 

Urgent action is needed to mitigate further greenhouse gas emissions and to adapt to the new reality of a warming sea. Global and Mediterranean leaders must ensure that stronger actions and financial mechanisms for biodiversity and climate are agreed upon this year.