Investigating ocean acidification

Dr Nick Kamenos of Glasgow University is among 101 scientists from around 21 of the UK’s top scientific institutions investigating the effects of carbon-dioxide (CO₂) absorption on the chemistry of the ocean, as part of the £12m Ocean Acidification Research Programme (UKOARP).

The absorption of CO₂ from the burning of fossil fuels, as well as from other human sources, fundamentally increases the acidity of seawater, which in turn has considerable consequences for the life and processes within.

This ’acidification’ of the ocean is also likely to have a significant impact on marine biogeochemistry and biodiversity; however, changes could extend beyond this to the whole Earth system, via effects on air-sea gas exchange and sedimentation of material through the oceans.

The scale and nature of the effects of ocean acidification are still largely unknown and substantial research is needed so that society may deal with the problem effectively.

The £12m, five-year UKOARP is funded by the Natural Environment Research Council (NERC), the Department for Environment, Food and Rural affairs (Defra) and the Department of Energy and Climate Change (DECC).

As part of this consortium, scientists at Glasgow and Heriot-Watt Universities are conducting research into how ocean acidification and warming may affect UK marine habitats formed by coralline algae (maerl) and cold-water corals (Lophelia pertusa).

At Glasgow, Dr Kamenos will study how ocean acidification will affect maerl − a very slow-growing marine plant that can live for thousands of years and, like corals, provides a habitat for many other marine species.

He said: ’We will use an arsenal of new techniques to understand how ocean acidification changes the skeletons formed by the corals and maerl. If we can understand the fine-scale changes in their skeletons, we’ll be better equipped to predict how the habitats they form could change in the future.’

Dr J Murray Roberts at Heriot-Watt University, who studies cold-water corals, said: ’If the ocean-acidification projections are correct, waters that have been suitable for cold-water coral growth for many hundreds of thousands of years could become corrosive by the end of the century. Cold-water corals produce one of the most biodiversity-rich habitats in the oceans, but we’ve barely begun to understand their ecology and importance.’

Work has already begun to set up a new aquaria to keep maerl and corals alive at at Glasgow University and Heriot-Watt Universities.

The research will take three years and will involve intense periods of fieldwork on maerl beds and cold-water coral reefs. Researchers will spend at least two months at sea using the UK’s deep-sea remotely operated vehicle, ISIS, to study the cold-water corals at Mingulay and Rockall Bank.

Six projects have now been funded, each delivering a key part of the UKOARP, designed to answer the following questions:

• ’How much variability is there in oceanic CO₂ uptake and what are the trends for the future?’ Led by Prof Andrew Watson, University of East Anglia.
• ’What are the impacts of ocean acidification on key benthic (seabed) ecosystems, communities, habitats, species and their life cycles?’Led by Dr Stephen Widdicombe, Plymouth Marine Laboratory.
• ’How will ocean acidification affect the biology of surface ocean communities and biogeochemistry, and how might that feed back to climate?’ Led by Dr Toby Tyrrell, National Oceanography Centre.
• ’What are the potential impacts of ocean acidification on the ocean and how it might amplify rising CO₂ and climate change?’ Led by Dr Andy Ridgwell, Bristol University.
• ’How will ocean acidification impact ecosystems and chemical cycling in UK and Arctic regional seas?’ Led by Dr Jerry Blackford, Plymouth Marine Laboratory.
• ’What were the effects of rapid ocean-acidification events in the Earth’s past?’ Led by Prof Paul Pearson, Cardiff University.

The UK researchers will collaborate with international colleagues − primarily with the German Bioacid programme, the European research programme EPOCA and the emerging US Ocean Acidification research programme.