Ocean acidification due to increasing atmospheric carbon dioxide

Ocean acidification due to increasing atmospheric carbon dioxide Contents Page Summary vi 1 Introduction 1 1.1 Background to the report 1 1.2 The oceans and carbon dioxide: acidification 1 1.3 Acidification and the surface oceans 2 1.4 Ocean life and acidification 2 1.5 Interaction with the Earth systems 2 1.6 Adaptation to and mitigation of ocean acidification 2 1.7 Artificial deep ocean storage of carbon dioxide 3 1.8 Conduct of the study 3 2 Effects of atmospheric CO 2 enhancement on ocean chemistry 5 2.1 Introduction 5 2.2 The impact of increasing CO 2 on the chemistry of ocean waters 5 2.2.1 The oceans and the carbon cycle 5 2.2.2 The oceans and carbon dioxide 6 2.2.3 The oceans as a carbonate buffer 6 2.3 Natural variation in pH of the oceans 6 2.4 Factors affecting CO 2 uptake by the oceans 7 2.5 How oceans have responded to changes in atmospheric CO 2 in the past 7 2.6 Change in ocean chemistry due to increases in atmospheric CO 2 from human activities 9 2.6.1 Change to the oceans due to CO 2 enhancement in recent centuries 9 2.6.2 How oceanic pH will change in the future 9 2.7 The role of carbon chemistry in ocean systems 10 2.7.1 Effects on calcium carbonate and saturation horizons 10 2.7.2 Impacts of acidification on the chemistry of nutrients and toxins 12 2.8 Conclusions 13 3 Biological impacts: effects of changing ocean chemistry on organisms and populations 15 3.1 Introduction 15 3.2 Effects of ocean acidification on photosynthetic and non-photosynthetic microorganisms 16 3.2.1 Effects on phytoplankton: photosynthetic organisms 16 3.2.2 Effects on non-photosynthetic microorganisms 18 3.3 Effects of ocean acidification on photosynthesis in benthic organisms 18 3.4 Effects of ocean acidification on multicellular animals 19 3.4.