Since the start of the industrial revolution, it is estimated that the ocean has absorbed approximately one third of the CO2 released by human activities, resulting in a 26% increase in the acidity of the ocean. This process, a threat to marine biodiversity, is still relatively little understood, though research is growing rapidly. The Intergovernmental Oceanographic Commission (IOC) of UNESCO contributes to this field of study through various initiatives, among which the ‘Ocean in a High-CO2 World’ Symposium Series and the Global Ocean Acidification Observing Network.
A global issue with local effects, consequences of ocean acidification include reduced coral growth and biological diversity, decreased shellfish settlement, and variation in fish behavior. All these changes cause ecosystems and marine organisms to change, potentially affecting food security and limiting the capacity of the ocean to further absorb CO2 from human emissions.
Despite advances in understanding the repercussions of elevated CO2 concentrations, we are still unable to make meaningful projections of impacts on marine ecosystems and fisheries as a whole, or to identify thresholds beyond which marine ecosystems may not recover. Methods must be developed to examine the full ecosystem response to multiple environmental factors.
The ‘Ocean in a High-CO2 World’ Symposium Series, held every four years since its first edition in 2004 at UNESCO Headquarters, brought ocean acidification as an important anthropogenic CO2 issue to the forefront of research. As a cofounder, IOC participated to the 4th International Symposium from 3 to 6 May in Hobart, Australia.
The four-day event built on the successful three previous symposia and offered the worldwide community of scientists working to understand ocean acidification opportunities to share their research results and develop new research collaborations. 335 participants from 28 countries attended the conference, tackling various themes, among which:
- Organism responses to ocean acidification;
- Ecological effects of ocean acidification;
- Changing carbonate chemistry of the ocean;
- Advances in ocean acidification research and monitoring;
- Ocean acidification and society – from mitigation to food security;
- Ocean acidification and the increasingly crowded ocean – global change multistressors.
During the conference, Kirsten Isensee (IOC project specialist, Ocean Science) highlighted Ocean acidification and its relevance in international treaties: “Ocean Acidification is part of the political agenda, measuring its impacts is one target of the Sustainable Development Goal 14. This conference gives the opportunity to shape the implementation of this target and to equip the nations to fulfill their commitment.”
A series of workshops that amplified some of the major themes of the symposium took place prior to or after the main meeting, also in Hobart. These less formal workshops consisted of oral presentations, discussion sessions and, in some cases, hands-on practical sessions. One of them was the 3rd Global Ocean Acidification Observing Network (GOA-ON) Science Workshop, from 8 to 10 May, co-organized by IOC.
A coordinated multidisciplinary approach involving both observations and modeling is needed to understand how ocean acidification affects marine ecosystems and biogeochemistry in open ocean and coastal environments, as well as its socio-economic implications. Following two workshops in 2012 and 2013, GOA-ON was established as a collaborative international initiative (now with more than 240 members from 45 countries) guiding the development of an integrated network for the detection and attribution of ocean acidification and ecosystem response.
This 3rd workshop, attended by more than 130 participants from 35 countries (7 African countries represented), aimed to further the development of GOA-ON by:
- Providing updates on GOA-ON national and regional status and linkages to other global programs;
- Promoting the development of regional hubs to facilitate national programs and capacity building;
- Discussing modeling connections, observational challenges and opportunities;
- Presenting advances in technologies, data management and products;
- Gaining input on data product and information needs, as well as regional implementation needs.
The GOA-ON Mentorship Program, a scientific mentorship program that matches senior researchers with early career scientist to provide professional guidance and technical support, was also launched on this occasion. The network encourages its members to assist and help scientists, who just started to be aware of the impacts of ocean acidification, and welcomed numerous new participants from Africa and the Western Pacific.
The ocean is a vital source of nourishment, especially to people in the world’s poorest nations. Many depend on fish for their primary source of protein: fisheries and aquaculture support the livelihoods of about 540 million people (8% of the world’s population). Given the likelihood that ocean acidification will negatively affect biodiversity and commercial fisheries, global policies are essential to insure against extreme food shortages that could lead to famine, increased poverty and conflicts, including war. Learning to manage our ocean sustainably is the only path to global prosperity and peace.