Deep ocean storage of CO_2 captured from flue gases is being considered as a potential response option to global warming concerns. For storage to be effective, CO_2 injected into the deep ocean must remain sequestered from the atmosphere for a long time. A fraction of CO_2 injected into the deep ocean must remain sequestered from the atmosphere for a long time. A fraction of CO_2 injected into the deep ocean must remain sequestered from the atmosphere for a long time. A fraction fo CO_2 injected into the deep ocean is, however, expected to eventually evade into the atmosphere. This fraction is estimated to depend on the time after injection, the locatin of injection, and the future atmospheric concentration of CO_2 which will affect the future solubility of CO_2 in seawater. The evasion of injected CO_2 at specific locations can be approximated by a non-linear convolution model which explicitly includes the non-linear response of CO_2 solubility to future CO_2 concentration and Green's functions for the transport of CO_2 from injection locations to the ocean mixed layer. Gree's functions can be calculated from the results of models of ocean carbon cycle with deep ocean injection. To illustrate this method, the evasion of CO_2 impulses injected at locations in the Pacific and Atlantic oceans is estimated using a three-dimensional model for ocean carbon cycle. In this model CO_2 transport is governed by tracer transport in the ocean interior which makes use of a steady flow field generated by an Ocean General Circulation Model; exchange of CO_2 to the scenario for future CO_2 concentration. This modeling approach can be used to intercompare the results of different ocean carbon cycle models when models are run for different CO_2 concentration scenarios, and different injection protocols. Extension of this modeling approach to include effects of sediment dissolution are considered.
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