Paris climate pledge would help world fishing

Honouring the Paris climate pledge would provide a fair catch for the world’s fishing fleets. Warm up the oceans, though, and everyone loses.

LONDON, 12 March, 2019 – Canadian scientists have worked out the way to make the most of the world’s fish stocks: by honouring the Paris climate pledge.

Seagoing nations could raise revenues for their fishing fleets, put more seafood on the table and protect the most valuable commercial fish stocks simply by doing what they had promised in 2015 to do anyway.

The key is the historic agreement reached then in Paris by 195 nations, to take steps to limit average global warming to “well below” a total of 2°C above the long-term average for most of human history, and to do this by 2100.

In the last century or so the global temperature has already risen by around 1°C, as a consequence of ever-increasing combustion of fossil fuels that emit greenhouse gases into the atmosphere.

“The largest gains will occur in developing country waters … which are at the greatest risk due to warming temperatures”

But although the world agreed its ideal target, the action so far leaves it on course for a potentially catastrophic rise of 3.5°C by the end of the century.

“Achieving the Agreement’s target could increase global fisheries revenues by $4.6 billion annually, seafood workers’ income by $3.7 bn and reduce household seafood expenditures by $5.4 bn,” said Rashid Sumaila, of the University of British Columbia’s Institute for Oceans and Fisheries.

“The largest gains will occur in developing country waters, such as Kiribati, the Maldives and Indonesia, which are at the greatest risk due to warming temperatures and rely the most on fish for food security, incomes and employment.”

What the researchers did – they explain their approach in the journal Science Advances – was to match what the computer forecasts said the Paris target would deliver, with what might happen if the world went on burning oil, coal and gas under the notorious business-as-usual scenario.

Impacts on ecosystems

They looked at the impact of less or more warming on 381 marine species, including the 10 that generate the most money, and they included ecosystem consequences as well as the economic payoff promised by the Paris target.

Their conclusion is that three-fourths of maritime countries would benefit, with the largest gains to be made by the developing nations.

Under the Paris scenario, the total mass of the fish species that generate the highest revenues would increase globally by 6.5%, with an 8.4% increase in the waters of developing countries. Overall, developed countries would see a marginal fall of 0.4%.

The Paris option would see an additional 3.3 million tonnes landed sustainably every year, compared with the business-as-usual scenario.

Conservation also needed

The British Columbia scientists are not the first to make the case for Paris in terms of fishery revenues: US and Japanese scientists looked at the same problem last year and concluded that the Paris option – matched by careful conservation approaches – could yield more fish for the hungry, and more revenues for the fishermen, if the ocean temperatures were kept from rising too dangerously.

But all the signals so far are ominous. A warmer world means a stormier one and greater danger for fishing fleets. More carbon dioxide in the atmosphere means ever more acidic seas, which seems to affect fish behaviour and threaten marine habitats such as coral reefs and kelp forests.

The same rise in carbon dioxide will warm the oceans and drive fish to migrate. Overall, humans have already left the seas diminished, and worse could be on the way. Fishing and seafood support an estimated 260 million full-time and part-time jobs worldwide.

Many to benefit

The Science Advances study is a reminder that while change is inexorable, the worst need not be inevitable. All continents except Europe would benefit from implementation of the Paris Agreement.

But as fish move towards the poles, countries in northern Europe might benefit from greater choice in their waters, and losses in the overall catch might be buffered by hjgher prices for those fish actually landed.

Russia could see catches reduced by as much as 25% under the 1.5°C target rather than the 3.5°C forecast. “However a projected 19% increase in fish prices, known as the price effect, should result in a negligible loss of less than 2% in fisheries revenues in Russia,” said William Cheung, one of the co-authors, of the University of British Columbia.

“Conversely, for the US fishing revenues are expected to decrease by 8% due to price effects but will be offset by a 21% increase in catch potential.” – Climate News Network