Anmerkung: Cover -- Half-title -- Title -- Copyright -- Contents -- Preface -- Acknowledgments -- Contributors to the 1993 Global Change Institute -- I. INTRODUCTION -- Introduction -- References -- 1 Excerpt from 1994IPCC Report -- Summary -- The increase in atmospheric CO2 concentration since pre-industrial times -- The carbon budget -- Future atmospheric CO2 concentrations -- Stabilisation of atmospheric CO2 concentrations -- Feedbacks to the carbon cycle -- 1.1 Description of the carbon cycle -- 1.2 Time- Scales -- 1.3 Past record of atmospheric CO2 -- 1.3.1 Atmospheric measurements since 1958 -- 1.3.2 Pre-1958 Atmospheric measurements and CO2-Ice core record over the last millennium -- 1.3.3 The CO2 record over the last climatic cycle -- 1.4 The anthropogenic carbon budget -- 1.4.1 Introduction -- 1.4.2 Methods for calculating the carbon budget -- 1.4.2.1 Classical approaches -- 1.4.2.2 New approaches: budget assessment based on observations of13C/12C and O/N2 ratios -- 1.4.2.3 Constraints from spatial distributions -- 1.4.3 Sources and sinks of anthropogenic CO2 -- 1.4.3.1 Fossil carbon emissions -- 1.4.3.2 Atmospheric increase -- 1.4.3.3 Ocean exchanges -- Model results -- 1.4.3.4 Terrestrial exchanges -- 1.4.3.4.1 Emissions from changing land use -- 1.4.3.4.2 Uptake ofCO2 by changing land use -- 1.4.3.4.3 Other terrestrial sink processes -- CO2 Fertilization -- Nitrogen fertilization -- Climate effects -- 1.4.4 Budget summary -- 1.5 The influence of climate and other feedbacks onthe carbon cycle -- 1.5.1 Introduction -- 1.5.2 Feedbacks to terrestrial carbon storage -- Effects of temperature and CO2 concentration -- Effects of land use -- Soil feedbacks -- Nutrient limitation of CO2 fertilization -- 1.5.3 Feedbacks on oceanic carbon storage -- 1.6 Modelling future concentrations of atmospheric CO2 -- 1.6.1 Introduction. , 1.6.2 Calculations of concentrations for specified emissions -- 1.6.3 Stabilization calculations -- 1.6.4 Assessment of uncertainties -- References -- 2 Excerpt from 1995 IPCC Report -- Summary -- 2.1 Introduction -- 2.2 CO2 and the carbon cycle -- 2.2.1 Introduction -- Atmospheric CO2 levels -- The anthropogenic carbon budget -- The influence of climate and other feedbacks on the carbon cycle -- Modelling future concentrations of atmospheric CO2 -- 2.2.2 Atmospheric CO2 concentrations and the status of the CO2 growth rate anomaly -- 2.2.3 Concentration projections and stabilization calculations -- 2.2.3.1 Effects of carbon cycle model recalibration -- 2.2.3.2 Effects of uncertainties in deforestationand CO2 fertilisation -- 2.2.4 Bomb lifetime vs. perturbation lifetime -- 2.2.5 Recent bomb radiocarbon results and theirImplication for oceanic CO2 Uptake -- References -- II. THE MISSING CARBON SINK -- 3 Carbon Dioxide Emissions from Fossil Fuel Consumption and Cement Manufacture, 1751-1991, and an Estimate of Their Isotopic Composition and Latitudinal Distribution -- Abstract -- 3.1 Introduction -- 3.2 The 1950-91 annual time series -- 3.3 A1751-1991 time series -- 3.4 The latitudinal distribution -- 3.5 The isotopic signature -- 3.6 Epilogue -- Acknowledgments -- References -- 4 Emissions of Carbon from Land-Use Change -- Abstract -- 4.1 Introduction -- 4.2 Methods -- 4.2.1 Data -- 4.2.1.1. Rates and types of land-use change -- 4.2.1.2 Stocks of carbon per unit area in vegetation and soil -- 4.2.1.3 Changes in carbon stocks as a result of land-use change -- 4.2.2 A Model -- 4.3 Results -- 4.3.1 1980s -- 4.3.2 1850-1990 -- 4.3.3 Extrapolation to 1765 -- 4.4 Uncertainties -- 4.4.1 Comparison with other analyses -- 4.4.2 Rates of land-use change -- 4.4.3 Stocks of carbon in vegetation and soil. , 4.4.4 Changes in carbon stocks as a result of human disturbance -- 4.5 Gross versus net emissions -- 4.6 The Unidentified sink -- 4.6.1 The historical pattern of the unidentified sink -- 4.6.2 A northern midlatitude sink? -- 4.6.3 The capacity for a terrestrial sink to continue -- 4.7 Summary and conclusions -- References -- 5 The CO2 Fertilizing Effect: Relevance to the Global Carbon Cycle -- Abstract -- 5.1 Introduction -- 5.2 Mechanism of the CO2 fertilizing effect -- 5.2.1 Photosynthesis and photorespiration -- 5.2.2 Stomatal conductance -- 5.2.3 Dark respiration -- 5.3 Interactions of CO2 with other growth-determining environmental factors -- 5.3.1 Light -- 5.3.2 Temperature -- 5.3.3 Water -- 5.3.4 Nutrients -- 5.4 Applicability of controlled environment results to natural ecosystems -- 5.4.1 The issues -- 5.4.2 Leaf expansion -- 5.4.3 Root restriction -- 5.4.4 Photosynthetic acclimation -- 5.4.5 Nutrient availability -- 5.4.6 Native plants versus agricultural cultivars -- 5.4.7 Competition and community dynamics -- 5.4.8 C storage in relation to NPP -- 5.5 Ehat is the CO2 response function of primary productivity? -- 5.6 The potential magnitude of the CO2 fertilizing effect on the global c cycle -- 5.7 The role of the n cycle and n deposition -- 5.8 Should the CO2 fertilizing effect be detectable in tree rings? -- 5.9 Conclusions -- Acknowledgments -- References -- 6 Soils and the Global Carbon Cycle -- Abstract -- 6.1 Introduction -- 6.2 Pool of carbon in soil -- 6.3 The dynamics of the soil carbon system -- 6.4 Anticipated changes in soil organic matter -- 6.5 Conclusions -- References -- 7 Grasslands and the Global Carbon Cycle: Modeling the Effects of Climate Change -- Abstract -- 7.1 Introduction -- 7.2 Definition -- 7.3 Grassland productivity, burning, and soil carbon -- 7.4 Grassland links with climate and climate change. , 7.5 Model studies of ecosystem response -- 7.5.1 Modeling CO2 impact -- 7.5.2 Regional ecosystem modeling -- 7.5.3 Climatology -- 7.5.4 Regional climate changes and CO2 perturbations -- 7.6 Conclusions -- Acknowledgments -- References -- 8 Constraints on the Atmospheric Carbon Budget from Spatial Distributions of CO2 -- Abstract -- 8.1 The context -- 8.2 The theory -- 8.2.1 Representation -- 8.2.2 Mass-balance inversions -- 8.2.3 Inversion by fitting distributions -- 8.2.4 Statistical approaches -- 8.3 Inversion -- 8.3.1 The source deduction problem -- 8.3.2 General inverse problem theory -- 8.4 Practical aspects of inversions -- 8.4.1 Smoothing -- 8.4.2 Low-resolution synthesis inversion -- 8.4.3 Higher-resolution synthesis inversion -- 8.5 Error estimation -- 8.5.1 Statistical representation -- 8.5.2 Applications of error analyses -- 8.5.3 Model error -- 8.6 Results -- 8.7 Conclusions -- Appendix: Synthesis inversion for 1986-87 -- Acknowledgments -- References -- 9 Estimating Air-Sea Exchanges of CO2 from pCO2 Gradients: Assessment of Uncertainties -- Abstract -- 9.1 Introduction -- 9.2 Measurement precision -- 9.3 An estimate of uncertainty in the regional distribution of surface water pCO2 -- 9.4 Spring bloom -- 9.5 Skin temperature -- 9.6 Gas exchange rate -- 9.7 Concluding remarks -- Acknowledgments -- References -- 10 Atmospheric Oxygen Measurements and the Carbon Cycle -- Abstract -- 10.1 Introduction -- 10.2 Seasonal variations -- 10.3 Long-term oxygen depletion -- 10.4 Interannual variability -- 10.5 Summary -- Acknowledgments -- References -- 11 A Strategy for Estimating the Potential Soil Carbon Storage Due to CO2 Fertilization -- Abstract -- 11.1 Introduction -- 11.2 Background -- 11.3 Estimating soil carbon turnover times by using bulk radiocarbon measurements -- 11.3.1 Determining the global inventory of active soil organic matter. , 11.3.2 Turnover time model validation -- 11.3.3 Sensitivity tests -- 11.4 Greening -- 11.4.1 Greening model validation -- 11.4.2 Sensitivity tests -- 11.5 Conclusion and future research -- Acknowledgments -- References -- III. PALEO-CO2 VARIATIONS -- 12 Isotope and Carbon Cycle Inferences -- Abstract -- 12.1 Introduction -- 12.2 Atmospheric ∆14C change -- 12.3 The role of the oceans in the carbon cycle: importance of carbon isotopes -- 12.3.1 Oceanic uptake of anthropogenic CO2 -- 12.3.2 Deep sea circulation rates -- 12.3.3 Upper-ocean mixing rates -- 12.3.4 Future oceanic 14C and 13C/12C measurements -- 12.4 14C Time scale calibration -- Acknowledgments -- References -- 13 Shallow Water Carbonate Deposition and Its Effect on the Carbon Cycle -- Abstract -- 13.1 Introduction -- 13.2 Historical background -- 13.3 An integrated approach -- 13.4 The coral reef hypothesis -- 13.5 "Coral reef influence on the future of atmospheric CO2 contents -- 13.6 Summary -- Acknowledgments -- References -- IV. MODELING CO2 CHANGES -- 14 Future Fossil Fuel Carbon Emissions without Policy Intervention: A Review -- Abstract -- 14.1 Introduction -- 14.2 Long-term projections of global fossil fuel carbon emissions -- 14.3 Long-term projections of global energy production and use -- 14.3.1 Oil -- 14.3.2 Gas -- 14.3.3 Coal -- 14.3.4 Nuclear energy -- 14.3.5 Renewable energy sources -- 14.4 Regional long-term projections of carbon dioxide emissions -- 14.4.1 United states and other OECD countries -- 14.4.2 Centrally planned countries -- 14.4.3 Rest of the world -- 14.5 Regional long-term projections of energy consumption and production -- 14.5.1 United states and other OECD -- 14.5.2 Centrally planned countries -- 14.5.3 Rest of the world -- 14.6 Why forecasts differ -- 14.6.1 Uncertainty analysis results -- 14.6.2 Factor analysis of base case differences. , 14.6.3 Comparison of population and economic growth assumptions.