The ocean has absorbed about one third of the anthropogenic carbon dioxide (CO2) emissions since the industrial revolution, greatly reducing the impact of this greenhouse gas on the climate. However, this massive input of CO2 is generating global changes in the chemistry of seawater, especially on the carbonate system. These changes are collectively referred to as “ocean acidification” because increased CO2 lowers seawater pH (i.e., increases its acidity). Quantitatively, ocean acidity has increased by 30% (0.1 decrease in pH) since the beginning of the Industrial Revolution. It is predicted that the future CO2 absorption into the ocean will result in a decrease of pH of 0.3-0.4 and a 16% decrease in carbonate ion concentrations by 2100. According to geological records, this acidification is happening at rates not seen for at least 50 million years.
Recent studies have shown that the resulting decrease in ocean pH will make it more difficult for marine calcifying organisms, such as corals, molluscs, and calcareous plankton, to form biogenic calcium carbonate, and existing calcium carbonate structures will become vulnerable to dissolution. Thus, ongoing acidification of the oceans poses a threat to ocean-based security. Since this ocean acidification may be occurring more rapidly than prior ocean acidification events that are thought to have coincided with mass extinction events, there are concerns that marine ecosystems will change, that biodiversity will be lost, and that important ecosystem services that human societies depend upon for food security, livelihoods, and coastal protection could be significantly impacted. Unfortunately, the effects of ocean acidification on organisms and ecosystems remain poorly understood, with most of our knowledge based on simplified laboratory experiments.
The Western Pacific and its adjacent regions are among the richest and most productive in the world as a home to more than 600 coral species (more than 75% of all known coral species) and ~53% of the world’s coral reefs. Most Southeast Asian coastal communities are socially and economically dependent upon coral reef ecosystems and an estimated 70-90% of fish caught in Southeast Asia are dependent on coral reefs. Globally, it has been estimated that coral reefs support greater than 25% of all known marine species.
Despite the recognition that ocean acidification from increasing levels of atmospheric CO2 represents a major global threats to coral reefs and other calcifying marine organisms, awareness of the impacts of this ‘other CO2 problem’ has emerged only over the last decade. The ecosystem responses to ocean acidification are poorly understood in the region and more research and long-term monitoring are critically needed to develop meaningful projections on future impacts of ocean acidification on marine ecosystem, especially on coral reefs, in the region to enable resource and fisheries managers, and policy makers to develop effective long-term mitigation and adaptation strategies for the people of the region.
In this context, the IOC Sub-Commission for the Western Pacific (WESTPAC) aims to establish regional research and monitoring network on ocean acidification in the Western Pacific and its adjacent regions, and develop a regional program, as one regional component of the Global Ocean Acidification Observing Network (GOA-ON), to monitor the impacts of ocean acidification on coral reef ecosystems, mainly through a series of regional trainings & workshops, selection of pilot areas, and transfer of knowledge and technology among experts, institutions within and outside the region.
To this end, upon the generous support of the National Commission of Thailand for UNESCO, the first regional training workshop was scheduled for 19-21 January 2015 with the host of the Phuket Marine Biological Center.
The first regional training workshop aims to
• Improve the understanding, and develop regional capability of research and monitoring on ocean acidification in the Western Pacific and its adjacent regions;
• establish an ocean acidification monitoring and research network among scientists, institutions, and agencies in the region;
• share existing and proposed ocean acidification monitoring and research approaches, methods, and techniques;
• recommend efficient, robust, and cost-effective monitoring approaches;
• identify challenges and gaps in the development of a regional program to monitor the impacts of ocean acidification on coral reef ecosystems;
• explore the possibility, building on existing coral reef monitoring initiatives, of a joint long-term monitoring program on the impacts of ocean acidification on coral reefs, and of joint research on ocean acidification and its related changes/process in seawater chemistry in the region.
Based on outputs of the first workshop, the second regional workshop, supposed to be organized about 6 months after the first one, will focus on defining and agreeing upon a suite of metrics, which could discern, to the extent possible, attribution of changes to coral reef ecosystems in response to ocean acidification; recommend the most efficient, robust, and cost-effective monitoring approaches for these defined metrics; map gaps in current capabilities; and select pilot study areas for the application of the identified monitoring approaches.
The third workshop, one year after the second one, will be convened to evaluate and refine monitoring approaches, provide solutions to any technical problems incurred, and come up with a roadmap for the future.