Marine heat waves, large increases in ocean temperatures lasting for several days or even longer, are becoming increasingly frequent and intense as the planet heats due to human-caused greenhouse gas emissions.
There are already numerous records and investigations on the impacts of these extreme phenomena on marine life, with coral bleaching being one of the most well-known. Other effects include, for example, events of mass mortality of animals and of algae.
In addition, marine heat waves are also associated with an increased likelihood of extreme climate events such as cyclones and episodes of heavy rainfall.
Now, a new study, recognizing the gravity of environmental and ecological impacts, calls for greater attention to the consequences of marine heat waves for human health, both physical and mental.
In a paper published in the journal Nature Sustainability, researchers Laura Falkenberg from the University of Adelaide (Australia) and Bayden Russell from the University of Hong Kong argue that these extreme phenomena should be recognised as “a serious public health problem”. The duo contends that the impacts of marine heat waves on people have been largely ignored.
The authors of this study argue that prolonged periods of unusually high ocean temperatures can trigger a range of effects that, in the end, affect human health, from the intensification of extreme climate phenomena and the reduction of marine food sources to an increase in mental health problems in coastal communities.
“Marine heat waves are no longer considered just an environmental problem,” says Falkenberg. “They are increasingly understood as a human health problem.”
The first author of the study explains that marine heat waves can affect people’s health both directly and indirectly. And they can intensify storms and marine heat waves on land, reduce the availability and safety of seafood taken from the sea, jeopardize livelihoods, and contribute to anxiety, sadness and other mental health problems in communities that depend most on the health of the oceans.
The researchers consider that governments and health authorities should begin to treat marine heat waves in the same way as those that occur on land, with their inclusion in planning related to public health issues, the consideration of health impacts in coastal and marine management decisions, and the improvement of collaboration between marine scientists, health authorities and resource managers.
“Recognising these health impacts is the first step towards better protecting communities,” emphasises Falkenberg.
“If we limit ourselves to reacting only after disasters occur, we will continue to suffer more severe impacts than if we had acted proactively. By understanding the links between the health of the oceans and human health, we can develop better policies that protect both people and the marine ecosystems on which they depend.”
