Marine heatwaves are wreaking havoc on ecosystems and economies, leading to increased hurricane intensity, coastal flooding, and heightened inland rainfall, while also stressing fisheries and threatening food security.

Since the 1980s, ocean heatwaves have nearly tripled in length, with half of all such events since 2000 linked to human-induced climate change.

In regions like the Mediterranean, marine heat events are now occurring with temperatures 5°C above normal, resulting in up to 80 days of extreme heat annually, which translates to about one in five days.

Marta Marcos from the Mediterranean Institute for Advanced Studies highlights that over 90% of excess heat from greenhouse gas emissions is absorbed by the ocean, stressing the need to stabilize atmospheric temperatures to mitigate ocean warming.

Prolonged marine heatwaves are impairing the ocean's capacity to absorb carbon, which contributes to stronger storms and devastates underwater ecosystems such as coral reefs and seagrass meadows.

The degradation of critical habitats like kelp forests and coral reefs not only diminishes biodiversity but also increases the risk of coastal erosion, illustrating the extensive impact of these heatwaves on human and ecological health.