Scientists have revealed that some parts of the Mediterranean are this year more than 6C warmer than usual in comparison with previous years, which sparks fears that the sea's fragile ecosystems are suffering what can be called a "marine wildfire" and being changed forever by global warming.

Water temperatures have been since May well above average, peaking at 30.7C off the eastern coast of Corsica last weekend - the summer of 2022 is likely to record new numbers for both the duration and intensity of the marine heatwave.

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This month, several areas of southern France experienced record air temperatures, which accompanied low winds and produced a layer of surface water that is critically hotter and much deeper than normal, according to marine ecologists.

"A water temperature of 28C or 29C may feel pleasant to bathers, but it is worrying for the Mediterranean's ecosystems," Frédéric Denhez told BFMTV. "The Mediterranean is starting to resemble the Red Sea, and its species are not adapted to that."

Rubén del Campo of the Spanish national meteorological service told Le Monde that when cooler deep water no longer rises to the surface, native populations of "corals, of shellfish and of fish are suffering enormously" in the Mediterranian.

The Mediterranean is considered a biodiversity hotspot as it is home to around 10% of all marine species. "The most adaptable organisms will resist – although they may become weaker – by adjusting their physiology or migrating," Emilie Villar, a marine ecologist based in Marseille, said. "But weaker ones are likely to perish," she told La Provence newspaper, adding that 700 Mediterranean species are threatened with extinction. "If the shock lasts too long, or if the species is fixed and cannot migrate, others will fill the void – or, if conditions become too harsh, the Mediterranean risks dying out."

A recent study revealed that maritime heatwaves had so far destroyed up to 90% of coral populations in parts of the Mediterranean, with gorgonian corals and red corals particularly hard hit, as well as sea sponges and sea urchins.

David Diaz, a researcher at the Spanish Institute of Oceanography told Le Monde that such ocean heatwaves were "the equivalent of underwater wildfires, with fauna and flora dying just as if they had been burned".

Water temperatures raising concerns

Last year, a WWF report found that the Mediterranean water temperatures were rising 20 percent faster than the global average, making it the fastest-warming sea in the world.

About 1,000 exotic species had already migrated into the sea, the report said, some via the Suez Canal from the Red Sea. These species include 126 different kinds of fish, several of which are highly invasive and destructive of the Mediterranean's marine habitat.

The last date to record the temperature for the Mediterranean was in August 2018; the water off Marseille was measured at 6.6C higher than the average at the time of the year, while the sea's longest marine heatwave observed so far was in 2003, and it lasted from August 3 to September 2.

Climate change and marine life

Climate change has not only affected human life but also has been a great threat to wild animals, sea birds, and marine life. In June, locals in New Zealand gathered some 183 penguins they had found at the Ninety Mile Beach for later investigation in what appears to be the latest development in a phenomenon of dead penguins washing up on the island nation's beaches in vast numbers.

The kororā, a species of penguin characterized by its glossy blue color and known by the locals as little blue penguins, is the smallest species of the penguin family in the world, and they are native to New Zealand. But their population in the country is diminishing. The Department of Conservation classes the kororā as "at-risk" and "declining".

A DoC principal science advisor specializing in the field of sea birds, Graham Taylor, believes that more than 500 penguins have washed ashore since the start of May, projecting that the figure could be nearing 1,000. He also noted that it was difficult to give an accurate death toll, mainly due to the locals finding and burying many of them.

All of the bodies found on the sandy beaches of New Zealand were found extremely underweight, weighing less than their average size of 800-1000 grams.

However, it turned out that the kororā were not starving due to overfishing, but the main reason behind them not finding enough nutrients is the food chain disruption created by climate change, which is creating waters too hot for the fish they feed on.

Read: Global warming could lead to largest extinction of marine life