A new comment posted in the scientific journal Nature Climate Change By an international biologists team shows the devastating effects that marine heat waves caused throughout the world in 2023 and 2024. The increase in the average temperature of the sea surface – amplified by global warming, “the child” and a very low cloud – gave rise to an unprecedented number of extreme marine heat waves. In the last two summers, there were 240% more days of marine heat waves than in any other recorded (since 1983).
These record temperatures have serious consequences for marine ecosystems and, therefore, for coastal communities. “The main impacts of the sea waves that we have seen in the last two years have been the massive bleaching of corals, the appearance of species in new places and the number of extreme meteorological phenomena,” says Kathryn E. Smith, a doctor of the United Kingdom Marine Biology Association and the main author of the article.
The work performs an radiography of the effect of marine heat waves in the world: in New Zealand, in 2023, they caused the Gabrielle cyclone, which killed 11 people and caused damage worth more than 8,000 million dollars. They also caused that Peruvian anchovies They will move away from its usual waters, in 2023 and 2024, with estimated losses of 1,400 million.
In Europe, the increase in the temperature of the oceans caused the storm Daniel in 2023, which caused fatal floods in Greece, Bulgaria and Türkiye. Sea heat waves have also harmed fish populations and almost caused the extinction of the fan mussel in the Mediterranean. The populations of Marine Birds of Scotland were affected by decreasing their food sources, while aquaculture suffered losses due to the proliferation of harmful algae.
In front of the coast of northern Spain, marine heat waves have affected seafood. Catalan fishermen complain that The prawns and sardines have left to colder waters And every time they get more African achas. Meanwhile, invasive species such as lionfish, which, in addition to poisonous is typical of the Pacific Indo, begin to colonize the Mediterranean and are already present in the Canary Islands.
The work of ARIADNA MECHÓ, Biologist and researcher In the Department of Earth Sciences of Barcelona Supercomputing Center – National Supercomputing Center (BSC -CNS), it focuses on analyzing data to know how oceanic warming is affecting marine ecosystems. “Some species such as sardine in the Mediterranean or cod in the Baltic, begin to move to colder waters,” he emphasizes.
But this is not the worst of the consequences for fish. There are other species that “cannot be moved, because all their efforts are focused on surviving a climate that does not do well,” he says. That, he says, «makes them more fragile; more sensitive to any type of disease and, therefore, They can be extinguished».
As a conclusion, the work highlights that the ocean plays a vital role in the climate regulation, marine life and the supply of food and jobs. In the last two years, marine heat waves have forced to close fisheries and aquaculture, increased whales and dolphins and causes the fourth global bleaching of corals. Therefore, researchers encourage prevention measures to reduce their impact.
In Australia a quarter of the population of Nordic Gallineta, a species in danger of extinction, was transferred to aquariums before the heat wave and released again when the waters cooled. In the US, some corals and snails moved to deeper and cold waters. In Peru, the government paid benefits to fishermen who could not be done at sea when they were forced to close the fishery of anchovy.
Researchers consider that a better forecast and rapid response plans could have reduced impacts in other regions. In addition, they express that if the burning of fossil fuels and the logging of forest, the marine heat waves could be 20-50 times more frequent and ten times more intense at the end of the century.