November 30, 2018 —Climate change could devastate a major northern hemisphere fishing industry, modelling finds.
For cod facing the effects of climate change, it’s not the heat but the acid that threatens.
Ocean acidification – caused by atmospheric carbon dioxide entering the water and lowering its pH value – means there’s a narrower thermal window for the success of two species of northern cod, meaning that one of the world’s largest fisheries will be threatened if global temperature increases are not limited to 1.5 degrees Celsius, a new study finds.
The researchers, led by Flemming Dahlke of the Alfred Wegener Institute in Germany, find that embryos of cod are able to survive only within a limited temperature range, and that the range lessens in more acidic conditions.
The researchers predict that Atlantic cod (Gadus morhuai) would be unable to spawn below the Arctic Circle by 2100 under a “business as usual” emissions scenario. The polar cod (Boreogadus saida) faces an even more perilous future, since it not only needs colder water, but also depends on ocean ice for its habitat.