Global warming will reduce fishery biomass by 10% by 2050

Rome – By mid-century and under a high emissions scenario, exploitable fish biomass will be reduced by 10% due to the effects of global warming, according to a report published Wednesday by the Food and Agriculture Organization of the United Nations (FAO).

The document ‘Risks of climate change for marine ecosystems and fisheries: Projections to 2100 from the Marine Ecosystem Model Intercomparison Project’ also reflects that this percentage will be higher by the end of the century.

“Understanding the potential impacts of climate change on marine ecosystems and their fisheries, and the associated uncertainties, is crucial to designing adaptation programs at appropriate scales,” he claimed Manuel Barange, Deputy Director-General of FAO and of the Fisheries and Aquaculture Division.

By 2100, under a high-emissions scenario projecting global warming of 3 to 4°C, that reduction could be 30% in 48 countries and territories, while under a low-emissions scenario with warming of 1.5 to 2°C, that reduction stabilizes at 10% in 178 countries.

Among the most notable declines, the report includes those of the main fish producers, which worsened by up to 37.7% in areas of Peru and 30.9% in China, always in high-emission scenarios.

“Lower emissions significantly reduce end-of-century biomass losses in almost all countries and territories compared to the high-emissions scenario. This highlights the benefits of climate change mitigation measures for fisheries and aquatic food,” Barange added.

This document has been produced by an international network of researchers working with FAO to understand the long-term impacts of climate change on marine ecosystems and fisheries using state-of-the-art numerical models.

A comparison of projected losses under the two scenarios for the end of the century found that emissions reductions “had marked benefits for almost all countries and territories” and especially for small island states, where populations are heavily dependent on fishing.

In the Pacific, between 68% and 90% of the extreme losses projected by the end of the century under the high emissions scenario for the Federated States of Micronesia, Nauru, Palau, the Solomon Islands and Tuvalu would be avoided under the low emissions scenario.

The report comes shortly after the conclusion of the latest edition of the State of World Fisheries and Aquaculture conference, which revealed that global fisheries and aquaculture production reached a new high of 223.2 million tonnes in 2022.