The spotted pufferfish, once confined to tropical seas, now swims peacefully in the waters of the Mediterranean. On the Sicilian coasts, fishermen catch barracudas, a typical species of the eastern Atlantic. What’s happening? Is Mare Nostrum becoming tropicalised?
Two recent scientific studies confirm this the effects of climate change on temperature increase. The surface temperature of the Mediterranean it has increased by more than 1°C in the last 25 yearswhile at a global level we are dangerously close to the critical threshold of +1.5°C compared to the pre-industrial era.
The Mediterranean is transformed
Imagine taking a dip in the crystal clear waters of Sardinia in a few years. Instead of encountering schools of sardines and sea bream, you may only find yourself face to face with lionfish. It’s not science fiction, but one possible consequence of the warming of the Mediterranean.
A team of researchers from ENEA and INGV, in collaboration with the shipping company GNV, has monitored the temperature of the waters of the Ligurian and Tyrrhenian Seas for 25 years. The data, collected in 100 oceanographic campaigns, show an increase in average surface temperature of more than 1°C from 1999 to today.
And it’s not just the surface that heats up: even the deeper layers, up to 800 meters, record an increase of +0.4 – +0.6°C between 100 and 450 metersand +0.3 – +0.5°C between 450 and 800 meters. To get an idea of the energy involved, just think that to induce such an increase in temperature an amount of energy equal to tens of times Italy’s annual electricity consumption would be required.
This warming of the waters has a devastating impact on marine biodiversity. Many fish species, accustomed to lower temperatures, are forced to migrate north or to greater depths, while others, coming from warmer waters, are settling in the Mediterranean, altering the balance of ecosystems.
But that’s not all. The increase in water temperatures can affect marine currents and evaporationwith possible repercussions on the climate of the Mediterranean region. An increase in extreme weather events is expected, such as droughts, heat waves and floodswith significant impacts on agriculture, water resources and human health.
Antarctica raises the alarm: are we close to the point of no return?
As the Mediterranean transforms, another worrying signal arrives from Antarctica. A study published in Nature Geoscience, conducted by Lancaster University, analyzed ice cores extracted from the Antarctic continent, reconstructing the climate of the last 2000 years.
Researchers used a new analysis method, based on the measurement of stable isotopes of water trapped in ice, to more precisely determine temperature variations over the centuries.
The results of the study are clear: in 2023, human-induced global warming has reached +1.49°C (± 0.24°C) compared to pre-industrial levels. We are therefore dangerously close to the threshold of +1.5°C, the limit beyond which scientists predict an acceleration of the effects of climate changewith potentially irreversible consequences.
The increase in temperatures in the Mediterranean and in the global average temperature are two manifestations of climate change. A complex phenomenon that manifests itself with different intensities and modalities in the various regions of the globe, but which has a common cause: the emission of greenhouse gases resulting from human activities.
