23 Sept 2019 - (CNN) Humanity is exacting a terrible toll on the ocean. The Intergovernmental Panel on Climate Change (IPCC) will publish its Special Report on the Ocean and Cryosphere in a Changing Climate later this week. Its overarching message will be that global warming, combined with the negative impacts of numerous other human activities, is devastating our ocean, with alarming declines in fish stocks, the death of our reefs, and sea level rise that could displace hundreds of millions of people. But there is a glimmer of hope -- there is now overwhelming scientific evidence that the ocean can be a potent force in stabilizing the climate and building a secure future for everyone.
Ocean-based climate solutions could deliver as much as 21% of the emissions reductions needed to limit global warming to no more than 1.5 degrees Celsius by 2050. These reductions could amount to 11.8 gigatons of carbon dioxide equivalent, or CO2e -- a standard unit that measures the impact of greenhouse gases in relation to the effects of CO2. This figure is greater than the current emissions from all coal-fired power plants worldwide.
These are the key figures from a new report released today, commissioned by the High Level Panel for a Sustainable Ocean Economy composed of 14 prime ministers and presidents, which we are proud to chair. It demonstrates in detail, for the first time, how a sustainable ocean economy could play a much bigger role than we previously thought in shrinking our carbon footprint, achieving the goals of the Paris Agreement, and delivering on the Sustainable Development Goals set forth by the UN in 2015.
Given the report's findings, the High Level Panel is launching a Call to Ocean-Climate Action at the U.N. Climate Action Summit in New York today. The call presents a list of five actions we can take to boost ocean health and mitigate the climate crisis.
The first thing we should do is scale up ocean-based renewable energy (such as offshore wind turbines and new technologies to harness the energy of waves and tides). As an alternative to fossil fuels, this has the potential to cut the most emissions -- as much as 5.4 gigatons of CO2e annually by 2050. That's the equivalent of taking over a billion cars off the road for a year.
We also need to ramp up our ambitions to decarbonize shipping and marine transport; fortunately, many of the solutions to do this already exist. It is also crucial to protect and restore mangroves, seagrasses, salt marshes, and other coastal and marine ecosystems that face a huge threat from over-development. Doing so would prevent significant quantities of greenhouse gases from entering the atmosphere by increasing nature's capacity to sequester carbon. Additionally, developing low-carbon sources of protein from the ocean -- like seafood, seaweeds and kelp -- can provide a healthy and sustainable diet for future populations while easing emissions from land-based food production.