Nearly 70% of all oceans are set to lose some pelagic animal biomass, according to recent research.
Climate change can influence many meters below the sea surface, putting at risk species that serve as food for certain animals consumed by humans, warns research recently published in the journal Nature.
The pelagic environment, an area of the ocean where living things that do not depend on the seabed generally inhabit, will be the most affected.
“Nearly 70% of all oceans are going to lose some of that animal biomass,” says the research.
The international team of researchers used an innovative methodology, based on the study of the seabed and the subsequent construction of a special model to predict the impact of climate change.
“We have compiled and used the largest database of observations made with underwater sonar in previous regional studies,” oceanographer Alejandro Ariza, one of the authors of the article, revealed, quoted by the French Research Institute for Development (IRD). .
“We estimated the distribution and abundance of animals in the water column. It has never been done on this scale, that is, over 350,000 kilometers in the entire ocean, except in the polar circles, ”he added.
The scientists concluded that low and mid-latitudes may lose between 3% and 22% of animal biomass: fish, molluscs, jellyfish and other marine species, many of which are consumed by humans.
Global warming
“Many of these organisms are involved in vertical carbon migration, also called the oceanic carbon pump,” Ariza clarified. “Therefore, reducing the abundance of this fauna will reduce the retention of atmospheric CO2 in the oceans, which will accelerate global warming,” he warned.
However, the study reveals that this scenario can be avoided. It is estimated that if the increase in global temperatures remains below 2 °C, the impact on fauna would be reduced by less than half, indicates the UMR Marbec research unit.