We have all heard about how climate change and pollution are affecting our oceans but rising ocean acidification has rarely been part of those discussions: It’s less obvious, less sexy, and more insidious than other dangers. The Economist Impact and the Nippon Foundation have launched an initiative to address this threat and they’ve call it “Back to Blue”, in reference to the pH values.
The standard definition of pH is “A measure of how acidic or basic a substance or solution is. pH is measured on a scale of 0 to 14. On this scale, a pH value of 7 is neutral, which means it is neither acidic nor alkaline. A pH value of less than 7 means it is more acidic, and a pH value of more than 7 means it is more alkaline.”
The ocean absorbs CO2 from the atmosphere and thus helps mitigate global warning by removing this “greenhouse” gas. However, the ocean is not a bottomless sink, and every molecule of CO2 is absorbs makes it a little more acidic.
The world’s CO2 emissions are not just warming the planet and the oceans, they are creating a threat to many types of marine life by reducing the alkaline levels and, by definition, increasing the acidity. Currently, and naturally, the oceans are alkaline with a pH value around 8 but this value is dropping.
Steve Widdicombe, the director of science at Plymouth Marine Laboratory and co-ordinator of the Ocean Acidification Research for Sustainability (OARS) program, has described the process as follows:
“Ocean acidification, warming and de-oxygenation are interacting with each other to create a “perfect storm” of environmental challenge”.
When CO2 dissolves in the oceans, it releases carbonic acid. Carbonic acid depletes the carbonate that marine organisms need to create their hard outer structures; examples would be shellfish and corals coral. This reduction in the alkali levels results in thinner shells, more fragile coral, reduces the level of protection against predators, and the ability to grow and reproduce. This has a profound effect on habitat for many species of fish and, consequently, an effect that moves right up the food chain to humans.
We know from long experience, although we don’t seem very good at acknowledging it or incorporating it in our “development” plans, that every action we take with nature upsets the traditional environmental balance in some way. To state the obvious, we are all connected, and our short-sighted and selfish approaches will hasten our demise as a species, taking many others with us, unless we wake up and do something about it.
Scientists warn that, even if we slash carbon emissions, some warm-water and polar species will be at high risk of acidification’s impacts by 2100. If emissions continue unabated, many more species and habitats will be at high risk as early as 2050 – that’s less than 30 years’ time. Again, that will definitely affect the food chain and, therefore, eventually threaten our survival. This is not just an abstract, paternalistic concern for the planet and other species, this is about our survival as the human species. Addressing the problem seriously is in our own selfish interests, if nothing else.
What can we do?
- Expand the use of climate-smart marine protected areas to develop new methods of mitigating against or adapting to acidification.
- Support the development of technologies that extract carbon from sea water.
- Widen the use of mangroves, seagrasses and other nature-based solutions to capture and sequester carbon before it reaches seawater.
- Step up research that advances our knowledge about acidification, including how it impacts marine coastal ecosystems.
- I would add a major international education campaign that rallies the general public to force the politicians into action. The general public needs to realise what is at stake. Currently they have no idea, except perhaps intellectually, and even that only applies to a minute percentage of the world’s population.
Do we want the human species to survive? That sounds a bit dramatic, but we stand a chance of becoming extinct while we’re walking along the street texting away about regular inconsequential nonsense.