CO2 changes

The estimated response time of CaCOa compensation, on the order of a few thousand years, is a serious problem because the ice core data do not show such a long delay in atmospheric CO2 changes with respect to temperature changes. Such a long delay may preclude CaCOa compensation as an important process in predicting atmospheric CO2 in the next few centuries. 

Martin, J. H. (1990). Glacial-interglacial CO2 change The iron hypothesis. Paleoceanography 5,1-13. 

Broecker, W. S. and Henderson, G. M. (1998). The sequence of events surrounding Termination II and their implications for the cause of glacial-interglacial CO2 changes. Paleoceanography 13,352-364. 

Recently, Ishikawa (1996), and Kashiwagi et al. (2000) calculated CO2 change in atmosphere during the last 30 Ma and the last 60 Ma respectively, mainly based on the method developed by Berner et al. (BLAG model) (1983), Bemer (GEOCARB model) (1994), and Tajika (1998) taking into account hydrothermal CO2 flux from back arc basins and island arcs which were not considered in previous studies. 

A cosolvent used as a miscible additive to CO2 changed the properties of the supercritical gas phase. The addition of a cosolvent resulted in increased viscosity and density of the gas mixture and enhanced extraction of the oil compounds into the C02-rich phase. Gas phase properties were measured in an equilibrium cell with a capillary viscometer and a high-pressure densitometer. Cosolvent miscibility with CO2, brine solubility, cosolvent volatility, and relative quantity of the cosolvent partitioning into the oil phase are factors that must be considered for the successful application of cosolvents. The results indicate that lower-molecular-weight additives, such as propane, are the most effective cosolvents to increase oil recovery [1472]. 

Figure 9.4 shows one interpretation of the atmospheric CO2 history of Earth over a time period of 100 million years. The geologic record of atmospheric CO2 will be addressed in detail in Chapter 10 of interest here is the possibility that humankind activities of fossil fuel burning and land use practices could lead to future atmospheric CO2 levels rivaling those of the past. Furthermore the future time scale of atmospheric CO2 change may be shorter than any period of CO2 change the Earth has experienced in 100 million years. 

Predictions of atmospheric CO2 change depend not only on choices concerning future energy sources but also on the rate of world population growth, and the ultimate maximum energy consumption per capita. These estimates are difficult to make, but various scenarios have been developed to provide some limits on future CO2 concentrations. 

Broecker W.S. and Peng T-H. (1987) The role of CaC03 compensation in the glacial to interglacial atmospheric CO2 change. Global Biogeochemical Cycles 1, 15-30. 

Ziegler-Natta-type catalysts, which are active in polymerization and oligomerization of alkenes. are also influenced by adding CO2 to the reaction mixture. The addition of CO2 changes the molecular we t and crystallinity of the products or the activity and selectivity of the catalyst, both in polyethylene [307,308] and in polypropylene production [309-312]. 

Putting aside the question of the relationship between change in surface temperature and changes in CO2 content and focusing on projections of CO2 changes in the atmosphere over the next 100 years, could you summarize for us the three major uncertainties, two or three major uncertainties in that prediction and suggest research to eliminate those uncertainties or reduce them ... 

Volk, T., and Hoffert, M. I. (1985). Ocean carbon pumps Analysis of relative strengths and efficiencies in ocean-driven atmospheric CO2 changes. In The Carbon Cycle and Atmospheric CO2 Natural Variations Archean to Present (Simdquist, E. T., and Broecker, W. S., eds.). American Geophysical Union, Washington, D.C.Geophys. Monogr. Set. AGU. Vol. 32, pp. 99—110. 

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