As world leaders prepare for international climate change negotiations next week in Durban, South Africa, a new study out this week depicts the widespread threats that climate change presents for marine fisheries.
The bottom line? Emissions from the burning of fossil fuels are presenting very long-term if not irreversible threats for the oceans.
Economists and top fisheries scientists at the University of British Columbia published a paper on Sunday in the journal Nature Climate Change that outlines the many challenges fisheries face from climate change, and how this can impact the global economy and hundreds of millions of lives.
Global marine fisheries are underperforming, mainly from rampant overfishing, but climate change also creates several serious threats to the future productivity of fisheries. These chemical and physical changes linked to climate change such as decreased oxygen levels, changes in plankton communities and plant growth, altered ocean circulation and increased acidity can disrupt the basic functioning of marine ecosystems and thwart any potential recovery of global fish stocks.
The study outlines how impacts can scale up from changing ocean conditions to the global economy, but the authors note that the true scope of impacts to employment are hard to predict.
Some sobering news for the oceans this Earth Day. A new congressionally requested study by the National Research Council concludes that “the chemistry of the ocean is changing at an unprecedented rate and magnitude due to anthropogenic carbon dioxide emissions” and that “the rate of change exceeds any known to have occurred for at least the past hundreds of thousands of years.”
The study finds that the oceans have absorbed about one-third of total carbon dioxide emissions over the past 200 years - which has made the oceans more acidic - and the acidity will continue to rise because CO2 emissions are rising too rapidly for the oceans to cope.
Ocean acidification, says the report, can disrupt important physiological processes in marine creatures, such as shell and skeleton building, internal fluid and tissue pH maintenance and carbon fixation in photosynthesis.
And while we don’t yet know the ultimate consequences for ecosystems, we do know that coral reefs, fisheries, protected species and other valuable natural resources are at risk.
The bottom line here is that ocean acidification will continue unless anthropogenic CO2 emissions are substantially curbed -- Take action today by telling your representative to support further research on ocean acidification.
Ellycia Harrould-Kolieb is a climate scientist at Oceana.