Two fishermen clean their catch on board a fishing trawler

Future catches could be much smaller than these fishermen’s haul off the British coast. Credit: Annie Sakkab/Bloomberg/Getty

Climate change

A warming planet will devastate fisheries

High greenhouse-gas emissions will divert nutrients that fuel the food web.

Unabated climate change will slash global fish catches over the next few centuries — and could reduce total plant life in the oceans for a millennium.

Fishing fleets will fare worst in the North Atlantic, where catches are expected to drop by nearly 60% by 2300, according to modelling done by Keith Moore and Weiwei Fu of the University of California, Irvine, and their colleagues. Globally, fish stocks will drop by roughly 20% in the same period, assuming greenhouse-gas emissions remain high.

The team found that phosphorus and other nutrients currently distributed by ocean currents will be trapped in the deep oceans as wind patterns shift, sea ice melts and oceans warm. Over time, ever-greater stretches of water will become starved of the nutrients that power the marine food web. Lower nutrient levels spell fewer fish.

These changes will not be reversed until the climate cools, the authors say.