World’s leading marine scientists expressed alarm over the rapid acidification of the oceans caused by carbon dioxide emissions, threatening the world’s already fragile marine life.
The huge amounts of carbon dioxide being absorbed by the world’s oceans is making it more acidic and could destroy coral reefs, fisheries, habitats and other ocean ecosystems, scientists told the delegates of the International Atomic Energy Agency Scientific Forum in Vienna, Austria last week.
Sam Dupont of Sweden’s Gothenburg University said acidification was a big stressor of the oceans upon which over half of the world’s population depends for its primary source of food.
“ There is a need to cut carbon dioxide emitted to the atmosphere. We can only do that if all governments take drastic actions and address climate change,” Dupont said. “More research is also needed for ecological restoration.”
According to IAEA, ocean acidification occurs as oceans absorb the rising quantities of carbon dioxide in the atmosphere. When dissolved, the carbon dioxide forms carbonic acid, creating a more acidic environment, which can threaten marine ecosystems.
The oceans not only produce as much as half of the world’s oxygen; they also absorb more than a quarter of man-made CO2. This reduces the greenhouse effect, but it also increases the acidity of seawater, resulting in a hostile environment for calciferous plankton, crustaceans, molluscs and coral reefs. With all parts of the ecosystem connected, all life in the oceans suffers from the increased level of acidity.
The latest report from the Intergovernmental Panel on Climate Change (IPCC) shows that the ocean is shielding humanity from climate change impacts at significant cost to its own health, says the Global Ocean Commission.
The UN’s climate change assessment panel found that the ocean is absorbing 93% of the heat trapped in the climate system by humanity’s emissions of greenhouse gases. The ocean is also absorbing a quarter of our carbon dioxide emissions, which is causing seawater to acidify at a rate possibly unprecedented in 300 million years.
The report from the IPCC’s Working Group One, on the physical science basis of climate change, shows that:
- the upper part of the ocean is warming by about 0.1C per decade
the deep ocean is warming too, and will continue to do so for centuries even if emissions are curbed immediately
- sea levels are rising, currents are changing, the rapid shrinking of Arctic sea ice is freshening water around the region, and concentrations of dissolved oxygen are declining
- acidification will make up to half of the Arctic ocean uninhabitable for shelled animals by 2050.
“ Corals and other marine organisms, specifically those with shells and skeletons, are at particular risk,” said Fernando Siringan of the University of the Philippines – Marine Science Institute.” It is one of the most important issues facing us today and we need to urgently address it.”
Raphael Bille from France’ Institute for Sustainable Development and International Relations, said that there are four possible actions to take against ocean acidification. He said there is an urgent need to limit the carbon dioxide emissions and other greenhouse gas emissions in the atmosphere; build resilience in marine ecosystems to better tolerate its impacts; repairing damages when the ocean has already acidified through ecological restoration projects; adaptation to ocean acidification such as relocation of commercial fishing activities to complement local adaptation strategies.
“ Ocean acidification is a global issue and needs to be addressed globally. There is no easy solution to ocean acidification. It is one more reason why climate change talks must succeed,” Bille said.
“In dealing with threats to the health of the seas, governments need accurate data. For that, they need skilled researchers who can devise accurate models to help predict future conditions. That way, governments can start implementing the appropriate strategies to protect the seas and oceans,” IAEA Director General Yukiya Amano told participants in the IAEA’s Scientific Forum, titled The Blue Planet – Nuclear Applications for a Sustainable Marine Environment.
“The IAEA helps to make this possible. We promote a comprehensive approach to the study, monitoring and protection of marine, coastal and terrestrial ecosystems. We support effective global cooperation to address the threats to our oceans.”
Since the oceans are changing, Professor Bernard Bigot, Chairman of the French Alternative Energies and Atomic Energy Commission, highlighted the need “to encourage individuals, international organizations, all stakeholders to work together to adopt measures. Simply, everyone is affected by these changes. Oceans acidification is a threat. Everyone is responsible for the environment and we should act together.”
To solve the problem created by human activities contaminating and stressing the ocean, “cross-disciplinary approaches are needed,” said David Osborn, Director of the IAEA Environmental Laboratories in Monaco. “Those involved in nuclear science, the life sciences, economics, the social sciences and policy makers must cooperate to promote holistic ecosystem-based approaches to today’s problems in the marine environment.”
By Imelda V. Abano
photos: Yvette Lee and IAEA