The Effects of the Climate Crisis on Oceans Will Be More Intense Than Previously Believed

Global warming will have a greater negative impact on marine ecosystems than has been projected in previous research, according to new work done with highly advanced and accurate climate models.  Experts urge effective mitigation and adaptation measures as both biodiversity and the future of fisheries are under increasing threat from climate change.

Picture from Source 2

Man-made increases in global temperatures are a growing threat to marine ecosystems.  This is revealed by the results of an international ecological modeling study, recently published in the journal Nature Climate Change.

According to research, the negative effects of global warming are intensifying on marine animals.  These suffer an increase in natural mortality, a reduction in calcification in the tissues of organisms and a modification of the distribution in the ocean.  Interactions between species, abundance and a general decrease in their biomass are also altered. The research has been carried out by an international scientific team of 36 researchers, two of whom are Spanish: Jose A. Fernandes and Marta Coll, experts in big data and ecosystem modeling at AZTI, a center specialized in the marine environment and the food, and the Higher Council for Scientific Research (CSIC), respectively.

"Projections of the impacts of climate change on marine ecosystems reveal a long-term decline in global marine animal biomass and show that the consequences for fisheries are unevenly distributed," the authors state.

The new simulations, much more advanced and accurate than previous ones, show that high warming and changes in nutrient and food availability will create a more marked decline in animal biomass in the world's oceans than previously projected.  Reducing uncertainty about how marine ecosystems will respond to the climate crisis will contribute to more effective adaptation and mitigation planning, the scientific team indicates.

"Although our results show worrying trends, we also highlight the importance of better understanding regional changes, where considerable uncertainty remains and yet there is an urgent need to help adaptation," explains Derek Tittensor, lead author and researcher at Dalhousie University (Canada).  The results are part of the Fisheries Models and Marine Ecosystems Intercomparison Project (Fish-MIP), an initiative that aims to answer questions about the future of fisheries, the supply of seafood, marine biodiversity and the operation of the marine ecosystems.

“The project brings together disparate models of marine ecosystems so that we can better understand and predict the long-term impacts of the climate crisis on fisheries and marine ecosystems, and provide a database that helps inform fisheries policies, climate change and biodiversity ”, emphasize the researchers.

Fernandes underlines that it is a “critical moment to mitigate and adapt to climate change.  We have to bet on digitization and new ways of working that allow us to be more efficient and cause less impact.”

This research represents a step forward in planning future pathways to sustainability and an important contribution to the sixth assessment report of the Intergovernmental Panel on Climate Change (IPCC AR6), which is scheduled to be published next year. Furthermore, it is of particular relevance to the Glasgow Climate Summit (COP26) in November, where world leaders will discuss their commitments to combat the climate crisis.

Sources: 

1. Tittensor, Derek. “Next-Generation Ensemble Projections Reveal...” Nature Climate Change, 21 Oct. 2021, www.nature.com/articles/s41558-021-01173-9.

NASA Climate Kids. “Make It Yourself: An Ocean Ecosystem Dessert.” Newsela, 19 May 2017, newsela.com/read/elem-miy-ocean-dessert/id/30540.