What’s the cost of coral? The value of tuna? It’s a challenge to put a number on something as large as the world’s oceans, but values can help to raise awareness of the importance of conservation.
A new study by an international group of scientists is putting a number on the value of the world’s oceans—and telling what the losses could be if the oceans are damaged. The report from SEI, the Stockholm Environment Institute, (PDF), which was presented at the "Planet Under Pressure" conference in London, estimates that if human impacts on the ocean continue unabated, the cost to the world’s economy will be $428 billion per year by 2050, and $1.979 trillion per year by 2100.
Alternatively, steps to reduce these impacts could save more than a trillion dollars per year by 2100, reducing the cost of human impacts to $612 billion.
The study looked at six different threats to the ocean: ocean acidification, ocean warming, hypoxia (low oxygen), sea level rise, pollution, and the overuse of marine resources. While previous calculations have tried to put a number on the value of the marine environment, this one is unique in tabulating the interactions between and among multiple threats, the study’s authors say. For example, the bleaching of coral reefs often occurs when global stressors, like increasing temperature and acidification, meet local stressors like pollution.
The study also tried to unravel more complex feedback loops, like the triple-whammy effect of ocean acidification, warming, and hypoxia on marine resources. Protein from fish accounts for 20% of the intake of animal protein for 1.5 billion people and 15% for about 3 billion people. In poorer coastal areas this figure can reach 90%.
The world’s marine fisheries are in a severely troubled state: 85% of fish stocks are fully exploited, over-exploited, depleted, or recovering from depletion, say the scientists. Harmful subsidies continue to contribute to the overcapacity of the global fishing fleet, inconsistencies in regional fisheries management lead to poor regulation, and illegal and unreported fishing—estimated to drain $50 billion from the sector every year—remains largely unstoppable.
What’s the good news? A new potential market in "blue carbon" could also present an important economic opportunity, says the SEI. Marine ecosystems, like mangroves and sea grasses, contain far more carbon than terrestrial forests but are being degraded at a more alarming rate and are not yet included in carbon offset schemes, which reward investors in emissions-reduction projects in developing countries with carbon credits. Setting up a market for the carbon-sucking value of those ecosystems could help conservation—and people in emerging economies. Local actions can make a global difference. Globally and locally acting stressors are closely linked, says the report, meaning that coordinated small-scale interventions can aggregate upwards to have major significance.