UN General Assembly to explore impact of ocean acidification

15 June 2013

15th June 2013

This week UKOA's Dr Phil Williamson and Dr Carol Turley are joining the United Nations General Assembly to consider the impact of increasing ocean acidification on the marine environment and people as the theme of this year’s informal consultative process on oceans.

Drs Williamson and Turley are both part of the UK delegation attending the Assembly, being held from 17th to 20th June, and will be presenting evidence and taking lead roles in expert panels and side events, such as the Convention on Biological Diversity - Intergovernmental Oceanographic Commission of the United Nations Educational, Scientific and Cultural Organization (CBD-IOC) meeting on the impacts of ocean acidification on marine and coastal biodiversity.

By absorbing increased amounts of atmospheric CO₂ caused by human activities, oceans have become 30 per cent more acidic than they were at the beginning of the industrial revolution 250 years ago, according to data cited in a report by United Nations Secretary-General Ban Ki-moon to the General Assembly. It is predicted that by 2050 ocean acidity could increase by 150 per cent; a rate 100 times faster than any change in acidity experienced in the marine environment over the last 20 million years.

In a message for the recently observed World Oceans Day, Mr. Ban said: “If we are to fully benefit from the oceans, we must reverse the degradation of the marine environment due to pollution, over-exploitation and acidification.” He added: “Let us work together to create new waves of action for ocean sustainability — for people and the planet.”

Oceans are currently absorbing approximately 2 gigatons of carbon per year, which represents about 25 to 30 per cent of the annual carbon dioxide emissions caused by human activities.  Consequently, ocean surface waters are becoming progressively less alkaline as a result of a chemical process generally referred to as ocean acidification.

Co-chairing the Open-ended Consultative Process on Oceans and the Law of the Sea will be Milan Jaya Nyamrajsing Meetarbhan and Don MacKay, Permanent Representatives of Mauritius and New Zealand, respectively. The Process, established in 1999, aims to identify areas in which international coordination and cooperation on ocean issues should be enhanced.

Over the course of four days, the meeting will focus on the scientific and technical aspects of ocean acidification. Participants will hear presentations from more than a dozen scientists and researchers about acidification, its effects and activities to address them, and how the issue may be more effectively addressed.

The Secretary-General’s report found that an emerging body of research suggests that ocean acidification will have varying impacts on marine organisms and ecosystems. But, it is also expected to have significant socio-economic impacts, particularly on communities and economic sectors dependent on oceans and their resources.

Acidification is likely to reduce the ability of oceans to absorb CO₂ and could compromise the health and continued function of many marine organisms. If pushed far enough, ecosystems may exceed a tipping point and change rapidly into an alternative state, with reduced biodiversity, value and function.

While it is still undetermined how ocean acidification would affect various species, corals, coccolithophores, mussels, snails, sea urchins and species requiring carbonate to build their shells are considered the most vulnerable.

The impact on people “could be profound”, the report says, as ocean acidification could alter species composition, disrupt marine food webs and ecosystems and potentially damage fishing, tourism and other human activities connected to the seas.

“While hard to predict, early estimates of the direct impacts of ocean acidification on marine fishery production are in the order of $10 billion per year,” the report states. A study estimated that the global and regional economic costs of production loss of molluscs due to ocean acidification would be over $100 billion by the year 2100.

There is currently no global international instrument dedicated specifically to addressing ocean acidification. However, elements of the existing legal and policy framework are relevant, including, first and foremost, the United Nations Convention on the Law of the Sea, which requires States to protect and preserve the marine environment.