Contents Acknowledgements vii Foreword Executive Summary Observed Impacts and Changes to the Climate System Projected Climate Change Impacts in a 4°C World Rising CO2 Concentration and Ocean Acidification Rising Sea Levels, Coastal Inundation and Loss Risks to Human Support Systems: Food, Water, Ecosystems, and Human Health Risks of Disruptions and Displacements in a 4°C World
List of Abbreviations
ix xiii xiv xv xv xv xvi xvii xix
1. Introduction
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2. Observed Climate Changes and Impacts
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The Rise of CO2 Concentrations and Emissions Rising Global Mean Temperature Increasing Ocean Heat Storage Rising Sea Levels Increasing Loss of Ice from Greenland and Antarctica Ocean Acidification Loss of Arctic Sea Ice Heat Waves and Extreme Temperatures Drought and Aridity Trends Agricultural Impacts Extreme Events in the Period 2000–12 Possible Mechanism for Extreme Event Synchronization Welfare Impacts
3. 21st Century Projections
How Likely is a 4°C World? CO2 Concentration and Ocean Acidification
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